Electronic Design|Schematic Circuit Power Diagram

Ultra Low Power LCD Indicator

2011-06-06T13:13:00.000-07:00

This circuit serves as an ultra-low power replacement for multiple LED on-off indicators. It also has the advantage of being easy to read in full daylight. With the parts shown, it is possible to display four bits of information.

The display that I used has three digits and 2 decimal points for a total of 23 segments. Different groupings of segments can be used for the four indicators. I chose to use three squares (shown) and the three lower segments together (not shown) for the four indicators. Many other combinations could be used, one possibility would be to hard-wire numbers or letters out of each of the digits. Other LCD displays could also be used for different effects.

A part that doesn't exist as far as I know, but should, is a single pixel LCD indicator (2 wire). An LCD manufacturer could probably make a lot of money with such a part. If such a thing exists, I'd love to hear about it.

Specifications

Operating Voltage: 3-15V (5V Nominal) DC
Operating Current: 250 microamps to 1 milliamp (400 microamps at 5V)
Operating Frequency: approximately 60 Hz

Theory

The 7555 IC (CMOS 555 timer) generates a square wave clock signal at approximately 60 hz. This signal is sent to the LCD backplane and the inputs of the four CMOS 4070 XOR gates. If the other input (ind*) of an XOR gate is low, the gate's output is a square wave that is in phase with the clock signal. If the ind* input is high, the gate's output is out of phase with the clock.

Sending a signal to an LCD segment that is in phase with the backplane signal causes the display to stay blank. Sending an out of phase signal to the LCD segment causes an AC waveform to be applied to the segment which turns it black. Multiple segments are wired in parallel to generate the desired display patterns. The LCD segments require a tiny amount of current to operate, the CMOS gates also take very little power, hence the efficient nature of the circuit. It is necessary to tie the unused segments to the LCD backplane, otherwise they may partially turn on.

If more dislay bits are needed, additional XOR gates can be connected in the same manner. Up to 23 XOR gates could be used to drive the entire display, but a microprocessor and driver software would probably be easier to put together. By generating all of the signals with a microprocessor, all of the driving circuitry can be eliminated.

Other logic families could be used to make this circuit, it should work with a standard 555 timer chip and a 74LS86 XOR gate (different pin out), for example. Some LCDs may not operate at very cold temperatures, an engineer at Lumex said that their components will work from -30C to +75C.

Construction

The circuit was built on a standard prototyping plug board. All of the parts can be purchased for under ten dollars.

Use

The four inputs of the CMOS 4070 IC can connect to outputs on a microprocessor, or any other logic output that needs monitoring. The supply voltage of this circuit should be the same as the driving logic's supply voltage.

Parts

1X Lumex LCD-S301C31TR 3 digit LCD display (from Digi-Key), or equivalent
1X CMOS 4070 quad XOR Gate, a CMOS 4030 should also work.
1X 7555 CMOS 555 timer chip
2X 100nF capacitor
1X 100uF 25V electrolytic capacitor
1X 10K 1/4W resistor
1X 100K 1/4W resistor

Reset Microprocessor RS-232

2011-06-06T13:10:00.000-07:00

Introduction

This circuit allows a remote microprocessor to be reset by a controlling host by sending a break signal over an RS-232 or RS-422 serial line. If the remote machine resets into a simple program loader program, it is possible for the host to halt and restart, or halt and reload/restart the remote machine's program. This is an ideal way to develop software on older EPROM-based systems. Modern EEPROM/NVRAM systems use JTAG interfaces for similar results.

The remote processor runs its target code out of RAM, allowing the code to be updated easily. The circuit is usually used for developing code on a target processor, but it can also be used for permanent applications where the target program lives on a host system's disk. This system was once used to load code into a microprocessor-based satellite receiving system in Hawaii from a host system in Colorado using an Internet-based remote serial communications program.

A program loader for the Z80 CPU is available below. The circuit has also been used with the Motorola 68HC11 EVB and the BUFFALO monitor program. See my Linux Cross Assemblers page for more info.

Theory

This circuit detects long duration zero level signals (breaks) on a NRZ (non return to zero) serial data line. Normal serial characters spend a short time in the zero state, and do not cause a reset. Break signals are a exception to this, they hold the line low for an extended period.

The 10K/1N4148 parts keep the 2.2uF capacitor charged up. Low input signals go through the 10K resistor and slowly pull the charge on the 2.2uF capacitor down. High input signals quickly recharge the capacitor through the 1N4148 diode. A break signal lasts long enough to discharge the 2.2uF capacitor to the point where the following gate changes state.

The 1N4148 on the right allows a manual break switch to be used on the target CPU, pressing such a switch does not short out the preceding 74HC14 gate. This circuit could be built with just 2 schmidt trigger non inverting buffers, the 74HC14 was chosen because it is a common part. The parallel inverters are also optional, single inverters work fine.

source : http://www.solorb.com

Nine Volt Battery Eliminator Circuit

2011-06-06T12:58:00.000-07:00

Nine Volt Battery Eliminator Circuit

Effect pedals for electric guitars are typically powered by 9 volt batteries. These batteries cost several bucks each and don't often last very long. Leaving a pedal turned on overnight by accident guarantees a dead battery in the morning. Why spend your precious money on a constant supply of batteries when you can build this easy substitute that won't fade away right in the middle of that killer guitar solo. This device is not limited to use in guitar pedals, it can be used with guitar tuners, radios and other small 9V devices. The circuit can be built to support DC or AC wall warts, the AC version requires a bridge rectifier. I've build many of these out of surplus materials, they make good gifts for guitar players.

If an AC wall wart is used, the low voltage AC is sent to the input of bridge rectifier BR1. The pulsating DC output from BR1 is sent to the voltage regulator's DC input. Power from a DC wall wart should be fed directly to the DC Input pins. DC Wall wart power generally needs more filtering. C1 reduces the ripple in the DC supply. A larger capacitor may be substituted for C1, that is generally only needed for higher power loads. The smoothed DC power is fed to the input of VR1, the 7809 regulator. The 7809 produces 9V regulated DC at the output side. C2 filters load ripple on the output side of VR1. The regulated and filtered 9V DC supply is sent to the load device via 9V battery clips. The 9V DC power is also sent to an optional LED, a high brightness red LED is a good choice here, but almost any LED will work.

Wall Wart Selection

Wall warts can often be found for very small prices at yard sales and second hand stores. However, printed wall wart voltage and current ratings are often very inaccurate and the output voltage can drop a lot under load. It should be possible to sort through a collection of transformers to find ones that are suitable for use with this circuit. Generic wall warts with an output rating of 12VDC are usually a good bet for this application.

Voltage Tests

Before connecting the wall wart to the 9V regulator circuit, check the wall wart's output with a volt meter. The output of DC wall warts should be in the range of 11-16VDC for use with this circuit. The output of AC wall warts should be between 9-14VAC. Connect the DC wall wart supply to the regulator circuit or connect the AC wall wart to the bridge rectifier in front of the regulator circuit.

With the transformer plugged in and nothing connected to the output, measure the DC input voltage to the 7809. It should be a minimum of 11V for proper regulation. If the DC input voltage is raised too high, the 7809 may become very warm. 16V is a good input voltage upper limit. A larger heat sink and bigger container should be used if the circuit is to be used with higher input voltages and/or load currents that approach the 1 amp maximum rating of the 7809 regulator IC. If the output is at a steady 9V, connect the load (pedal) and measure the VR1 input and output voltages, the output voltage should remain at 9V and the input voltage should stay above 11V for good regulation. If the output voltage drops below 9V with the load connected, the wall wart's current rating is probably too low for the load. Substitute a wall wart with a higher current output rating.

Construction

The battery eliminator circuit is simple enough to wire with a direct point-to-point construction style. A small piece of perforated board also makes a good base for the project. Just be sure that no wires can cross if the external leads are pulled on. Small bits of black electrical tape can be wrapped around various connections to prevent shorts.

With a little effort, the regulator circuit can be built so that it fits into a 35MM film cannister. A small notch should be cut in the edge of the cannister to allow the wires to pass through. The wires should have a knot on the inside of the cannister to keep them from pulling on the internal components. The small film cannister is best for small loads, larger devices will cause the voltage regulator to get hotter and will need more air space and a bigger heat sink. For setups that approach the 1 Amp current limit of the 7809 regulator, the circuit should be mounted in a small aluminum box and the regulator should be bolted to the side of the box for good heat dissipation.

Be sure to compare the polarity of the adapter's battery snap to a 9V battery, reversed polarity can damage some guitar pedals. Some pedals use a coaxial DC power connector for auxilliary power. If you can find the appropriate mating connector, that is the preferred way to connect the battery eliminator. Be sure to observe the correct polarity on the connector, it varies from device to device.

Use

Plug the battery snap into the pedal's internal battery connector and plug the wall wart transformer into an outlet, connect the guitar and amplifier cables and you're ready to go. It may be possible to use one of these power adapters for more than one effect, this depends on the effect's battery ground polarity as well as the current consumption of the combined pedals. Generally, it is best to use one power adapter per effect pedal, this also lowers the the chance of creating hum from a ground loop.

Other Output Voltages

If the DC device you wish to power uses something other than 9V, this circuit can be adapted. For a 6V DC ouput, replace the 7809 regulator with a 7806 regulator. A 3V DC output can be achieved by using an LM2737ED-3.3 device, those can be purchased at Jameco.com. In general, the input voltage to the voltage regulator should be a few volts higher than the output voltage or the regulator won't be able to do its job. If the input voltage is too high, the regulator may run too hot.

Energy Efficiency

Wall warts are famous for being "phantom loads" that waste power 24-7-365 if they are left plugged in. If you leave a bunch of wall warts plugged in all of the time, your monthly energy bill will go up. A multi-outlet switched plugstrip makes a good master power switch for a guitar amp and some assorted wall warts, and it will save wear and tear on your amp's power switch.

Parts

PS1: Wall Wart power transformer, 12-16VDC or 9-14VAC
BR1: 1 Amp bridge rectifier (used with AC transformer only)
C1: 1000uF 25V electrolytic capacitor
C2: 100uF 25V electrolytic capacitor
VR1: 7809 voltage regulator
R1: 680 ohm 1/4W resistor
LED1: high output red type
Aluminum heat sink, TO-220 size
9V battery snap connector or coaxial DC connector
battery snap conectors may be scavenged from an old 9V battery
plastic film cannister or other plastic box

12 Volt 9 Amp Solar Power Center Kit System

2011-06-06T12:49:00.000-07:00

The SPC3 kit contains all of the circuitry for a medium-sized solar power system. It includes a solar charge controller for battery charge regulation, a smart on/off power switch with automatic low voltage disconnect operation and a built-in white LED lighting system. Additional lights and other 12V devices can be connected to the load terminals and controlled by the SPC3. The SPC3 can regulate up to 9 amps of incoming solar power and can switch an external load of up to 10 amps. The SPC3 can be used as a stand-alone solar powered lighting system controller for a one room building or RV/camper. The SPC3 can also be used to power other 12V loads such as radios, communication equipment, small TVs, recording equipment, fans, cameras and more. The SPC3 can be installed in both stationary and mobile environments.

The SPC3 should not be used for powering devices with high surge currents such as large motors or high powered car stereos. The SPC3 charge controller section includes: a battery float voltage adjustment, a red/green Charge/Float state indicator LED and battery equalize terminals for occasional overcharging.
A temperature sensor is included so that solar battery charging is temperature compensated. The SPC3 load controller section includes: a momentary action on/off switch for turning the load power and built-in white LEDs on and off, two bright white LEDs for a built-in light source, a low battery indicator LED that warns of impending shutoff and a low voltage disconnect circuit that disconnects the load when the battery discharges below a preset minimum voltage.

Source : http://www.cirkits.com/spc3/index.html

VHF Antenna Amplifier Circuit Using BFT66 Transistor

2011-06-04T10:06:00.000-07:00

VHF Antenna Amplifier Circuit Using BFT66 Transistor

Here’s a design circuit for very simple antenna amplifier electronic circuit project can be designed using this circuit diagram. This antenna amplifier electronic circuit can be used for a frequency range between 1 and 300MHz. This circuit antenna amplifier can be used for high frequency and VHF band (for radio and TV) and will provide a 22 dB gain. This antenna amplifier electronic project has a very low noise, under 1.6dB. This is the figure of the circuit.

This VHF, FM amplifier circuit is constructed based on the BFT66 transistor connected in common emitter connection. L1 coil has a 6uH value, but can be used any coil for high frequency (with a value between 5.6 to 6.8 u H). L2 coil is an air core type coil and it has 5-6 turns (10mm long and 5 mm diameter). For L2 coil can be used a 0.25 mm Cuem wire. The pcb of this circuit must be placed near the antenna, in a small metallic box. This VHF antenna circuit must be powered from a 12 volts DC power supply circuit, you can use a 12 volt battery, because the current consumption of this circuit is very low under 10mA. You can replace T1 transistor with some other UIF similar transistor type which have a very low noise factor.

TinyCAD, the design of electronic circuits and electrical

2010-12-02T16:57:00.000-08:00

TinyCAD is a free program for the design of electronic circuits and electrical systems, supports standard and custom libraries.

It is able to generate simulations SPICE (Simulation Program with Integrated Circuit Emphasis). TinyCAD is capable of exporting models of electronic circuits in Word format image.

DOWNLOAD

4 Channel Home Audio Amplifier 11 watt using IC TDA1554

2010-11-25T19:06:00.000-08:00

This is a simple circuit. Just use a single IC, but the amplifier has 4 channels, 11 channels per watt, which is Philip IC TDA1554 number suitable for listening at home or in any vehicle. Just because the power supply 12-15 volt or will be used to expand any home theater sound system. The first 2-channel amplifier front speakers. And 2 to extend the back surround sound speakers also.
This circuit power supply 12 volts to 18 volts Power consumption at 5A. The input 4 input pins 1, 2, 17 and 18 is divided into a horizontal input inverter Ting 2 channels (Pin 1, 17). inverse model and input object 2 channels (pins 2, 6). That we can use that. To output phase to phase or did not return. The output will be the fourth slot on the leg 6, 8, 12, 10, with a C7-C10 serves to increase the low frequency stability better before you go to the speaker. The switch S1 acts on mute by pressing S1 will be closed sound system circuit in Mute, and if open circuit S1 standby ready to work. The C5 and C6 will filter light to smooth out and eliminate interference.

High & Low voltage cut-off with delay& alarm

2010-11-25T19:02:00.000-08:00

This straight forward circuit will protect electrical appliances from over voltage as well as under voltage.The circuit also produces an alarm when the power supply comes back.An ideal circuit for home to protect your valuable equipments from voltage fluctuations.
The same circuit with some modifications can be used to make a automatic voltage stabilizer. When the mains voltage is in the normal level ,the voltage at the negative terminal of zener diode D4 will be less than 5.6 Volts.At this condition transistor T1 will not conduct.The same time voltage at the negative terminal of zener diode D5 will be greater than 5.6 and so the transistor T2 will be conducting.The relay will be activated and the green LED wil be glowing.
When the mains voltage is higher than the set limit the transistor T1 becomes conducting since the voltage at the negative terminal of D4 is greater than 5.6 V.At the same time transistor T2 will be non conducting which results in the deactivation of relay to cut the mains supply from load.When the mains voltage is less than the set limit transistors T1 & T2 becomes non conducting making the relay to de- activate and cut the load from mains.? The timer NE555 is wired as a monostable multivibrator with a pulse width of 10ms.When the power comes back after a cut off a negative voltage is obtained at the trigger pin which triggers the IC NE555.The transistor T3 gets forward biased and it drives the buzzer to produce a beep as an indication of power resumption.Also the transistor T1 is made on which in turn makes T2 off.As a result the relay will remain de- activate for 10ms and this provides the sufficient delay and the equipment is protected from surge voltages.

Sound module upgrades with op-amp

2010-11-25T18:57:00.000-08:00

The CD / VCD player who uses the same listen to the audio quality is often poor. This is due to the IC Acting analog amplifiers. Most commonly used is the IC op amp.Cheap. Is a valuable slew rate low. It can not meet the immediate modification of the digital signal. The frequency response is not wide enough. Makes the sound come out with sharp and hard. We need to fix with an analog output amplifier with high efficiency. And a filter in excess of unnecessary. To eliminate the sharp sound.So this circuit. Should select the IC op amp with high quality. To get a value LEWIS Garrett with a high and expensive. The circuit is not the number IC op amp to be used depending on demand.
When raising the power supply circuit, the power sector through Direct loans isolates. Consisting of Q1, Q2, ZD1, ZD2, R5, R6, C10 and C11. The circuit Direct loans isolate the control voltage for supplying the integrated circuit is about 12V and-12V. The C5-C9 is a collector. bypass capacitor. Help in responding to high frequencies and reduce the leakage of the capacitor electronic highlighting of C4 and C3. When the input to the pin 3 bedroom inverse fitting IC1 to extend signal not to phase out the. Pin 6 and the signal part is fed back through R3 and R2. which is 1.3 times the growth rate C1 and C2 act to eliminate high frequency unnecessary. This circuit is a circuit that extends the ordinary. The principle that the resistance of the circuit high input, to prevent the loading of the amplifier’s original CD. And a low output resistance, so they can drive loads easily. The sound quality that have come out that is based on the IC op-amps used IC op-amp should choose the high slew rate opamp.

Led light based music circuit with LM3914

2010-11-25T18:52:00.000-08:00

This is a simple light running circuit by music This circuit is not difficult, is MONO, with a few accessories. Can be connected to the output of a CD or cassette player Time.

Operation of the circuit. Begins to be input via VR. The VR will function fine, signal strength coming. D1 will take disconnected hemisphere plus leaving only the signal hemisphere removed to activation of Q1. Signal is extended through Q1 to pin 5 input of IC1. By C1 forward delay of the IC is not the LED (connected to the output. of IC1) off immediately. The IC IC1 is finished. The act shows the effect of the voltage at IC1 pin 5 of the display by the LED to pins 1-19 of the IC, which is within range. compared to a multiple voltage standard circuits. The circuit can operate effectively. In the R1 that it will determine the current flowing through the LED. To prevent LED damage.
Use should be connected to the input of the circuit. To the speaker terminals, change the value of R3 is 10k and IC1 can choose to display two types Bar (Bar) when the pin 9 and a power source. Dots (Dot) on 9-pin to float to drop.

This is a simple light running circuit by music This circuit is not difficult, is MONO, with a few accessories. Can be connected to the output of a CD or cassette player Time.
Operation of the circuit. Begins to be input via VR. The VR will function fine, signal strength coming. D1 will take disconnected hemisphere plus leaving only the signal hemisphere removed to activation of Q1. Signal is extended through Q1 to pin 5 input of IC1. By C1 forward delay of the IC is not the LED (connected to the output. of IC1) off immediately. The IC IC1 is finished. The act shows the effect of the voltage at IC1 pin 5 of the display by the LED to pins 1-19 of the IC, which is within range. compared to a multiple voltage standard circuits. The circuit can operate effectively. In the R1 that it will determine the current flowing through the LED. To prevent LED damage.
Use should be connected to the input of the circuit. To the speaker terminals, change the value of R3 is 10k and IC1 can choose to display two types Bar (Bar) when the pin 9 and a power source. Dots (Dot) on 9-pin to float to drop.

7.2 Volt Field Charger

2008-10-08T12:21:00.001-07:00

The unit is novel as it’s display graph shows you the time the battery has been charging in 2 minute intervals up to 16 minutes when finished.... read more

LM3647 Reference Design

2008-10-08T12:19:00.002-07:00

The LM3647 provides a single-chip charge management solution for Nickel Cadmium, Nickel Metal Hydride and Lithium-Ion cells. The device handles the entire charging process from rejuvenating deeply discharged cells to providing a number of charge termination and maintenance options. The LM3647 Demo Board allows users to create a battery charging solution with little effort.

Link : http://www.national.com/an/AN/AN-1165.pdf

Low-Cost Anemometer Fights Dust

2008-10-08T12:19:00.001-07:00

This application note describes a low-cost circuit that can detect when a chassis fan filter has become clogged with dust. It does this by using a temperature sensor to determine the rate of cooling of a transistor in the air path of the cooling fan, thereby implementing a simple thermal anemometer.

source: http://pdfserv.maxim-ic.com/en/an/AN844.pdf

Active Antenna for AM-FM-SW

2008-10-08T12:16:00.001-07:00

Active Antenna for AM/FM/SW:

This simple little circuit can be used for AM, FM, and Shortwave(SW). On the shortwave band this active antenna is comparable to a 20 to 30 foot wire antenna. It is further more designed to be used on receivers that use untuned wire antennas, such as inexpensive units and car radios.

Click to View circuit

VHF-HF TRANSVERTER

2008-10-08T12:15:00.002-07:00

This little circuit is a transmitting and receiving converter (transverter) that converts a FT290 or similar multimode handheld transciever to the 14MHz amateur band. The project is a single board module that needs an external local oscillator, for example, the VHF harmonic oscillator (or QRP VHF FM TX) LO for transverter project. It should be a relatively simple matter of scaling coils and caps to convert other bands. You may choose to omit the TX/RX switching and the TX mixer and use this unit as a receive converter giving 14MHz - 16MHz coverage on a multimode VHF receiver.

If you choose to use the full transverter circuit then you will be pleasantly surprised at the spectral purity of the transmitted signals. All unwanted spurious signals and even oscillator breakthrough are well under -75dB at the output terminal. The HF TX output from the unit is about 2mW and will give a full ten watts from my 10-Watt HF linear amplifier. The VHF rig must be of the type that also delivers +10v DC at the antenna socket on transmit. This is true of the FT290, C58 and most multimode handportables.

Read More
http://web.telia.com/~u85920178/conv/conv-00.htm

Ham Radio Circuit - Morse Code Filter Project

2008-10-08T12:15:00.001-07:00

This project will help to filter out the interference signal and ensure that the signal received from the Morse code station stand out.

Read more : http://www.electronics-project-design.com/HamRadioCircuit.html

Morse Code Practice Oscillator

2008-10-08T12:14:00.000-07:00

This simple code practice oscillator project for beginners to Continuous Wave Morse Code uses a 555 timer to generate a dit or dah sound when the key is pressed.

Good Link
More circuit by IC 555
More about Oscillator Generator
More about Squarewave Oscillator circuit

Read link : http://www.electronics-project-design.com/CodePracticeOscillator.html

2.4GHz AntennaAlignement

2008-10-08T12:13:00.000-07:00

2.4GHz AntennaAlignement This paper attempts to provide some insight into the nature of radio propagation in that part of the spectrum (upper VHF to microwave) used by experimenters for high-speed digital transmission. It begins with the basics of free space path loss calculations, and then considers the effects of refraction, diffraction and reflections on the path loss of Line of Sight (LOS) links

Source : http://www.educypedia.be/electronics/antennawifi.htm

2.4 GHz low noise amplifier with the BFG480W

2008-10-08T12:12:00.000-07:00

2.4 GHz low noise amplifier with the BFG480W This application note gives an example of a 2.4 GHz LNA with the BFG480W. Because this LNA design has a high third order intercept value of 17 dBm (measured at input), it can be used for Wireless Local Area Network (WLAN) front-end and Wireless Local Loop (WLL) applications, pdf file

Soruce : http://www.educypedia.be/electronics/antennawifi.htm

2.45 GHz power amplifier with the BFG480W

2008-10-08T12:11:00.002-07:00

2.45 GHz power amplifier with the BFG480W At a frequency of 2.45 GHz, a supply voltage of 3.0 V, and a control voltage of 3.0 V, the amplifier delivers an output power of 19 dBm at an input power of 8 dBm, with a power added efficiency of 38 %, pdf file

Source : http://www.educypedia.be/electronics/antennawifi.htm

2.4 GHz WLAN Radio Interface

2008-10-08T12:11:00.001-07:00

2.4 GHz WLAN Radio Interface IEEE 802.11b radio interface, Radio signal propagation at 2.4 GHz, Link budget calculations, pdf file

Source : http://www.educypedia.be/electronics/antennawifi.htm

802.11 Wireless LAN Cards

2008-10-08T12:10:00.002-07:00

802.11 Wireless LAN Cards schematics

Source : http://www.educypedia.be/electronics/antennawifi.htm

Antenna Basics

2008-10-08T12:10:00.001-07:00

Antenna Basics 1/4 Wavelength Ground Plane, Yagi antenna, horn antenna, Parabolic Dish, focus f = D²/16.c ; D= diameter of the parabola, c is depth of the parabola, BiQuad antenna, pdf file

Source : http://www.educypedia.be/electronics/antennawifi.htm

Antenna construction

2008-10-08T12:09:00.000-07:00

Antenna construction Quarter wave omnidirectional antenna for 2.4 GHz, omnidirectional antenna, Omnidirectional collinear antenna for 2.4 GHz, Biquad antenna for 2.4 GHz, Biquad antenna as a 2.4 GHz feeder for a Parabolic Dish, Can antenna for 2.4 GHz, pdf file

Source : http://www.educypedia.be/electronics/antennawifi.htm

Antennetechniek voor WISPs

2008-10-08T12:08:00.004-07:00

Antennetechniek voor WISPs biquad, cantenne, Biloop antenne

Source : http://www.educypedia.be/electronics/antennawifi.htm

Antennas for 2.4 GHz WiFi

2008-10-08T12:08:00.003-07:00

Antennas for 2.4 GHz WiFi wide angle antenna for 2.4 GHz WiFi, sector antenna for 2.4 GHz WiFi, Modified 3D Corner Reflector Feed for SAT TV offset parabolic dish, 2 el. BiQuad Feed for Offset Dish at 2.4 GHz WiFi, ...

Link : Antennas for 2.4 GHz WiFi

Antennas & Transmission Lines

2008-10-08T12:08:00.001-07:00

Antennas & Transmission Lines omnidirectional antenna, biquad antenna, cantenne, horn antenna, Yagi Antenna, pdf file

Source : http://www.educypedia.be/electronics/antennawifi.htm

Antenna tuning pdf file

2008-10-08T12:07:00.003-07:00

Antenna tuning pdf file

Source : http://www.educypedia.be/electronics/antennawifi.htm

Antenna tuning pdf file

2008-10-08T12:07:00.001-07:00

Antenna tuning pdf file

Source : http://www.educypedia.be/electronics/antennawifi.htm

Micro Power AM Broadcast Transmitter

2008-10-08T12:06:00.000-07:00

In this circuit, a 74HC14 hex Schmitt trigger inverter is used as a square wave oscillator to drive a small signal transistor in a class C amplifier configuration. The oscillator frequency can be either fixed by a crystal or made adjustable (VFO) with a capacitor/resistor combination. A 100pF capacitor is used in place of the crystal for VFO operation. Amplitude modulation is accomplished with a second transistor that controls the DC voltage to the output stage.

AM portable radio receiver by ZN414 IC

2008-10-08T12:03:00.000-07:00

An AM portable radio receiver made from the ZN414 IC. The ZN414 ic has now been replaced by the MK484 which is identical in performance and pinout.

circuit 4013 Modula-8-Counter

2008-10-08T12:02:00.001-07:00

circuit 4013 Modula-8-Counter

circuit 4013 Divide by 2

2008-10-08T12:01:00.003-07:00

circuit 4013 Divide by 2

circuit 4027 divide by 2 counter

2008-10-08T12:01:00.001-07:00

circuit 4027 divide by 2 counter

circuit 4027 divide by 3 counter

2008-10-08T12:00:00.003-07:00

circuit 4027 divide by 3 counter

circuit 4-BIT Serial Shift Register by 4027

2008-10-08T12:00:00.001-07:00

circuit 4-BIT Serial Shift Register by 4027

circuit counter to N and HALT by IC 4017

2008-10-08T11:58:00.002-07:00

circuit counter to N and HALT by IC 4017

Counter to N and Recycle by IC 4017

2008-10-08T11:58:00.001-07:00

Counter to N and Recycle by IC 4017

Random number generator by ic 4017

2008-10-08T11:57:00.003-07:00

Random number generator by ic 4017

0-99 counter by IC 4017x2

2008-10-08T11:57:00.001-07:00

0-99 counter by IC 4017x2

Circuit 3 DIGIT EVENT COUNTER by IC 4553 + IC 4511

2008-10-08T11:56:00.000-07:00

Circuit 3 DIGIT EVENT COUNTER by IC 4553 + IC 4511

Circuit 6 DIGIT EVENT COUNTER by IC 4553 + IC 4511

2008-10-08T11:55:00.000-07:00

Circuit 6 DIGIT EVENT COUNTER by IC 4553 + IC 4511

10 Hz Timebase by IC 4017

2008-10-08T11:54:00.000-07:00

10 Hz Timebase by IC 4017

1 Hz Timebase by IC 4017

2008-10-08T11:53:00.000-07:00

Circuit 1 Hz Timebase by IC 4017

Logic Probe by 74LS47

2008-10-08T11:49:00.003-07:00

This circuit is a Logic Probe. It indicates the logic state of the node of any TTL logic circuit. To do that, we have to supply the probe with the same power of the circuit that we want to analyse: same Vcc and same GND. ...

4-bit µP's A/D converter decodes keypad's inputs

2008-10-08T11:49:00.001-07:00

Fig 1 shows a Mitsubishi M50927-XXXSP/FP 4-bit microcontroller decoding a 4×4 keypad using only four digital I/O lines instead of eight. Saving four of a 4-bit µC's precious I/O lines couild be significant. The 4-bit µC's ADC provides the key to the savings. The µC's output lines, F1 through F4, energize the keypad's column lines one at a time via 74HC4049 buffer/ driver. If a user presses a key, the µC's ADC reads an analog voltage coresponding to the row of the pressed key.

Link Source:http://www.edn.com/archives/1994/101394/21di6.htm

2-channel ADC tags its own output

2008-10-08T11:48:00.002-07:00

The circuit in Fig 1 shows a simple way to operate a 1-MHz, 12-bit ADC (IC1) in DMA mode while alternating between its two analog-input channels. The converter operates continuously, driven by the 1-MHz clock on the S/H input. Tying RD and CS low ensures that data are always present on the ADC's output bus. The outputs of the 74HC74 flip-flop, IC2, change state on the rising edge of the end-of-conversion (EOC) signal.

Source Link : http://www.edn.com/archives/1994/042894/09di4.htm

18-bit ADC uses PC's serial port

2008-10-08T11:48:00.001-07:00

A PC usually requires a plug-in ADC card to process analog signals. However, with the circuitry in Figure 1, a PC can communicate with an 18-bit ADC through its serial port. The port provides both positive and negative power supplies as well as control signals. IC1 is an 18-bit MAX132 ADC with a serial interface. It requires three input control signals, , DIN, and SCLK, and emits serial data, DOUT, and EOC (end-of-conversion) signals.

Source Link : http://www.edn.com/article/CA159691.html

12-bit converter upgrades µC's ADC

2008-10-08T11:46:00.000-07:00

The simple circuit in Fig 1 and an accompanying software routine let you easily substitute a multichannel 12-bit ADC for the 8-bit ADC internal to the 87C752 µC. A single assembly can then implement both the low- and high-performance version of a system. A socket lets you plug in the external ADC when you need it; otherwise, you plug in the network of 10 100V resistors. At power-up, the µC executes a routine that looks for the external converter.

Source Link : http://www.edn.com/archives/1994/070794/14di5.htm

CAPS PROVIDE VOLTAGE BOOST TO SERIES REGULATOR

2008-10-08T11:44:00.001-07:00

CAPS PROVIDE VOLTAGE BOOST TO SERIES REGULATOR
This circuit adds some capacitors and diodes to a traditional transformer type series regulator circuit to extend the normal operating range. It can insure regulation during low line voltage conditions or it can squeeze a few more watts out of a plug-in-the-wall power adapter power supply.

CAPS PROVIDE VOLTAGE BOOST TO SERIES REGULATOR

2008-10-08T11:44:00.000-07:00

240VAC TO 5VDC POWER SUPPLY

2008-10-08T11:43:00.002-07:00

240VAC TO 5VDC POWER SUPPLY
This is simple way to power some 5v logic from a 240vac source. If a 120vac power adapter is used, the circuit will also work for 120vac power lines.

LOW POWER 12,000 VOLT POWER SUPPLY

2008-10-08T11:43:00.001-07:00

LOW POWER 12,000 VOLT POWER SUPPLY
If you need about 12,000 volts DC for an ion generator this circuit might be the ticket. It draws power from the 120vac power line but it uses a small 6KV camera flash trigger coil. The output signal is isolated from the power line. Although the circuit can only deliver about 5uA of current it can produce dangerous shocks, so be careful.

MINIATURE ISOLATED AC/DC POWER SUPPLY

2008-10-08T11:42:00.000-07:00

MINIATURE ISOLATED AC/DC POWER SUPPLY

This circuit uses a novel approach to produce a fully isolated and regulated 5 volts @30ma from the 120vac power line. It uses two tiny SCRs that alternately discharge two capacitors through a miniature high frequency transformer. The voltage spikes produced through the transformer are rectified, filtered and regulated. A very common 8 ohm audio impedance matching transformer can be used for the transformer

Power Supply Converted from a PC

2008-10-08T11:41:00.002-07:00

Power Supply Converted from a PC

12V to 9V with a LM317

2008-10-08T11:41:00.001-07:00

12V to 9V with a LM317

9-V Stabilized Powersupply

2008-10-08T11:40:00.000-07:00

9-V Stabilized Powersupply

8A Regulated Power Supply for 13.8V

2008-10-08T11:39:00.002-07:00

Click 8A Regulated Power Supply for 13.8V

Variable 5 to 20V DC Supply

2008-10-08T11:39:00.001-07:00

Build your own 5-20V DC power supply using National Semiconductor LM2941 low dropout voltage regulator.

Read more : http://www.electronics-project-design.com/voltageregulator.html

Simple fixed 5V DC Power Supplies Project

2008-10-08T11:35:00.000-07:00

This project provides the schematic and the parts list needed to construct a simple Supply from an input supply of 7-20 V AC or 7-30V DC. Two DC voltage outputs are available; 5V and variable from 5V upwards.

Related Links
More about 5v dc supply circuit
7805+Mj2955 power supply 5V 5A for digital circuit.
Simple 5V 1A Switching regulator by IC LM2575-5.0
5V 5A switching regulator for digital by LM2678

Source : http://www.electronics-project-design.com/DCPowerSupply.html

Constructing a Dual Polarity Supply

2008-10-08T11:34:00.000-07:00

supply. With the appropriate choice of transformer and 3-terminal voltage regulator pairs you can easily build a small power supply delivering up to one amp at +/- 5V, +/- 9V, +/- 12V, +/-15V or +/-18V.

Read more : http://www.electronics-project-design.com/DualPowerSupply.html

Constructing a 12V DC Switch Mode Power Supply

2008-10-08T11:33:00.000-07:00

Construct a 12 VDC, 120 mA switch mode supply from AC source of 85-265 VAC.

Good Links
More Circuit construct a power supply
More circuit switch mode power supply
More Switching power supply Circuit
More about 12V power supply circuit

souec: http://www.electronics-project-design.com/SwitchModePowerSupply.html

DC DC Converter Circuit

2008-10-08T11:31:00.000-07:00

A DC-to-DC converter is a device that accepts a DC input voltage and produces a DC output voltage. Normally the output voltage produced is at a different voltage level than the input. DC to DC converters are used to provide noise isolation as well as power bus regulation. Some of the popular DC-to-DC converter topolopgies are:

1. BUCK CONVERTER STEP-DOWN CONVERTER

2. BOOST CONVERTER STEP-UP CONVERTER

3. BUCK-BOOST CONVERTER

Linear Technology DC DC Converter Module

The 10A High efficiency DC/DC converter module LTM4600 is a complete 10A, DC/DC step down power supply. Included in the package are the switching controller, power FETs, inductor, and all support components.

Operating over an input voltage range of 4.5V to 20V, the LTM4600 supports an output voltage range of 0.6V to 5V, set by a single resistor.

This high efﬁciency design delivers 10A continuous current, needing no heat sinks or airﬂow to meet power speciﬁcations. Only bulk input and output capacitors are needed to ﬁnish the design. The low proﬁle package (2.8mm) enables utilization of unused space on the bottom of PC boards for high density point of load regulation. High switching frequency and an adaptive on-time current mode architecture enables a very fast transient response to line and load changes without sacriﬁcing stability. Fault protection features include integrated overvoltage and short circuit protection with a defeatable shutdown timer. A built-in soft-start timer is adjustable with a small capacitor.

The features of this module are described below:

Wide Input Voltage Range: 4.5V to 20V
10A DC, 14A Peak Output Current
Parallel Two µModule™ DC/DC Converters for 20A
Output Current
0.6V to 5V Output Voltage
1.5% Output Voltage Regulation
Ultrafast Transient Response
Current Mode Control
Up to 92% Efﬁciency
Programmable Soft-Start
Output Overvoltage Protection

The typical application circuit of this device is as shown below.

USB Battery Charger Circuit

2008-10-08T11:30:00.001-07:00

This application circuit uses the MCP73853/MCP73855 linear charge management controllers for cost sensitive applications. They are specially designed for USB applications and adhere to all the USB specifications governing the USB power bus.

Read more : http://www.electronics-project-design.com/BatteryChargerCircuit.html

LX1970 VISIBLE LIGHT SENSOR

2008-10-08T11:27:00.000-07:00

The LX1970 light sensor can be used in conjunction with an LCD Front or Back Light Controller such as the LX1992 for LEDs or the LX1689 for CCFLs. This application note describes how to design in the LX1970.

Source: http://www.microsemi.com/micnotes/1403.pdf

Low-Cost Anemometer Fights Dust

2008-10-08T11:25:00.000-07:00

source: http://pdfserv.maxim-ic.com/en/an/AN844.pdf

Disappointed---Electronic

2008-10-08T11:19:00.000-07:00

Electronic

2008-10-08T11:15:00.000-07:00

electronic trance

2008-10-08T11:12:00.000-07:00

Electronic

2008-10-08T11:03:00.000-07:00

Transaksi dengan Perangkat Elektronik Harus Diakomodir RUU ITE

Telkom dan Telkomsel mengusulkan agar mayoritas transaksi elektronik menggunakan perangkat telekomunikasi --seperti SMS, rekaman suara, tampilan, WAP dan lainnya-- dapat diakomodasi dalam RUU ITE.
Demikian masukan RUU ITE dari PT Telekomunikasi Indonesia Tbk dan PT Telekomunikasi Seluler di Gedung DPR, Jakarta, Rabu (28/6). Dalam bahan masukannya, Telkom dan Telkomsel menyatakan bahwa hingga saat ini Indonesia belum memiliki regulasi yang secara khusus mengatur pemanfaatan serta perlindungan informasi dan transaksi elektronik. Padahal dalam transaksi elektronik para subyek hukum tidak saling bertemu. Maka harus ada suatu kepastian hukum yang menjamin bahwa transaksi tersebut bersifat otentik.

Sebagai suatu perbandingan, Eropa, Amerika dan negara maju di Asia telah memiliki regulasi yang mengatur pemanfaatan informasi dan transaksi elektronik serta memberikan perlindungan kepada kepentingan pribadi maupun publik.

Oleh karena itu, regulasi yang akan diterbitkan diharapkan memiliki sifat komprehensif, memuat seluruh aspek yang terkait dengan informasi dan transaksi elektronik. Perlu dilakukan review dalam mengantisipasi perkembangan teknologi. Selain itu, perluada perlindungan dan kepastian hukum, tidak saja bagi pengguna melainkan juga bagi penyedia layanan dan dunia bisnis yang terkait secara langsung.

Mengingat berdasarkan peraturan di bidang telekomunikasi mensyaratkan bahwa seluruh perangkat telekomunikasi yang dipergunakan operator telah melalui uji layak operasi (ULO); maka khusus perangkat yang telah melalui proses tersebut tidak perlu melalui prosedur sertifikasi lainnya seperti dimaksud dalam RUU ITE.

Selain itu, perlu ada perlindungan yang sama terhadap operator telekomunikasi sebagaimana yang diberikan kepada lembaga keuangan dalam RUU ITE. Misalnya ketentuan Pasal 31, 32 dan 33 dalam RUU ITE.Sementara Kepala Lembaga Sandi Negara RI Mayjen TNI Nachrowi Ramli, SE menyatakan bahwa LSN mendukung DPR agar segera mensahkan RUU ITE menjadi UU. Hal ini bukan saja mengikuti tren mekanisme perdagangan internasional secara elektronik, tetapi untuk melindungi kepentingan nasional kita.

“Jika RUU ITE bertujuan melindungi informasi dalam konteks hukum acara , sementara Sistem Persandian Nasional (sisdina) diperlukan untuk melindungi kemanan informasi baik dari aspek otentifikasi, keutuhan, privasi transaksi elektronik dan konfidensialitas konten informasi yang berkategori rahasia, maka RUU ITE juga berkaitan dengan Sisdina,” kata Nachrowi.

Nachrowi menambahkan bahwa aaspek penting transaksi elektronik yang menjadi kompetensi dan perhatian LSN adalah aspek keamanan, yang dalam konteks ini memanfaatkan mekanisme otoritas sertifikasi infrastruktur kunci publik atau kriptogradi kunci publik yang telah dirujuk dalam pasal 12, 13 dan 14 RUU ITE.

LSN menyoroti Bab VII tentang Perbuatan yang Dilarang, khususnya Pasal 26-34 RUU ITE, yang merujuk larangan akses tanpa hak terhadap sistem elektronik. Pembatasan tersebut untuk informasi yang harus dirahasiakan atau dilindungi, karena sistem keamanan yang tersedia masih terbatas pada keamanan akses dan identifikasi intrusi terhadap instalasi sistem elektronik, tetapi belum mengamankan konten melalui sistem enkripsi, khususnya yang menggunakan algoritma proprietary nasional.

Mengenai implementasi RUU ITE, baik berupa PP, Permen, dan lainnya, LSN menilai perlu dipertimbangkan aspek persandian. Oleh karena itu, LSN siap membantu pengelolaan pengamanan baik kriptografi kunci publik untuk transaksi elektronik, maupun dengan sistem persandian proprietary untuk mengamankan informasi pemerintah yang harus dilindungi dalam sistem/instalasi elektronik instansi pemerintah.

Tiny Dual-Axis MEMS Inclinometer Simplifies Industrial Measurements

2007-11-14T08:30:00.000-08:00

Targeting industrial applications, Analog Devices’ ADIS16209 dual-axis inclinometer and accelerometer breaks new ground in price, performance, size, and ease of use. The company claims this highly integrated device is the industry’s most accurate and easy-touse tilt sensor. It’s also 100 times smaller than other available devices.

The ADIS16209 offers a fully compensated direct digital output with less than 0.1° of linear inclination error. That makes it about three times as accurate as competitive tilt sensors, according to ADI. To boot, the company says that it has one-tenth the price tag of functionally equivalent competitive units.

The ADIS16209’s core is based on ADI’s dual-axis ADXL203 MEMS accelerometer. Its dimensions are a mere 9.2 by 9.2 by 3.9 mm, available in a laminate-based land-grid array (LGA) package.Many alternative tilt sensors make use of bulky fluid-filled electrolytic sensors, which can require special board mounting.

“While there are other inclinometers available that are fully calibrated, these are much larger in size. There are also many other small-size units, but these require extensive calibration procedures,” explained Bob Scannell, iSensor Business Development Manager for Analog Devices.

The ADIS16209’s small size enables users to place the device right at the point of applications, simplifying its use. It features dual-mode operation either as a dual-axis inclinometer with a ±30° range (operable to within ±90°) or a single-axis vertical mode within a ±180° range. It operates from a single 3.3-V power supply and typically dissipates 11 mA. The product is designed to withstand 3500-g shocks as well.

An embedded controller

The ADIS16209’s serial peripheral interface (SPI) enables simple integration into most industrial system designs. Thanks to an embedded controller, the chip is fully compensated for variances in bias, sensitivity, power-supply levels, cross-axis sensitivities, axial misalignment, non-linearity, and temperature drift.

Unlike other units on the market, which typically feature an analog acceleration signal output, there’s no need for users to perform sometimes extensive calibrations and adjustments. The tunable 14-bit digital sensor output data provides access to inclination (within 0.025° resolution) and acceleration (within 0.244-mg resolution). A simple internal register structure handles all output data and configuration features. Other features include typical low accelerometer noise of 1.7 mg rms and typical noise density of 0.17 mg/vHz rms. Offset error is rated within ±4 least-significant bits (LSB), and gain error is within ±2 LSB.

Additional features include typical alignment error (X sensor to Y sensor) of ±0.2°, an acceleration frequency bandwidth of 50 Hz, and a resonant frequency of 5.5 kHz. The ADIS16209 is rated for operation over the –40°C to 85°C temperature range. The accelerometer’s output in the self-test mode ranges from a minimum of 706 LSBs to a maximum of 1973 LSBs at 25°.

“The ADIS16209 provides an accurate and simple bits-out angle in a standard semiconductor format. This is a big departure from both electrolytic and less integrated MEMS-based sensors,” said Andy Garner, product line director for Analog Devices’ iSensor intelligent sensor products.

“The on-chip dynamic compensation of the ADIS16209 is important for two reasons. It allows our customers to confidently absorb mid-stream system design changes without losing their time-to-market advantage, and it provides end users with equipment that delivers accurate sensing data that is resistant to in-field environmental changes that can often result in costly, cumbersome recalibration,” Garner added.

One important feature is its programmable condition monitoring. Configurable operating parameters include sampling rate, power management, digital filtering, auxiliary analog digital outputs, offset/null adjustments, and selftesting for the integrity of the sensor’s mechanical structure.

The inclinometer’s combination of features makes it a natural for a host of industrial applications. These include surveying equipment, factory machine tools, satellite-antenna stabilization systems, robotics, motion-safety monitors for medical and security systems, and automotive wheel alignment.

Samples of the ADIS16209 sensor are available now at a price of $34.40 each in 1000-unit quantities. A complete evaluation board, the ADIS16209EVAL, is available for about $175. It includes a board-mounted sensor, interface hardware, and evaluation software. Volume production quantities are expected sometime this month.

What’s Hot? Try A New Capacitor Technology, Isolation Transformers, And Displays

2007-11-14T08:26:00.000-08:00

The fruit of a two-year research & development project, a unique and revolutionary capacitor technology from Electronic Concepts promises the highest level of protection against capacitor failure in catastrophic conditions. Known as Fuseac, the patent-pending technology addresses overheating concerns for metallized dry film capacitors in ac applications. In situations posing the threat of failure, Fuseac intuitively detects capacitor hot spots and disconnects the component when temperatures reach a critical value. Metallized film capacitors are fairly reliable on their own accord due to their self-healing capabilities. Yet too many selfhealing cycles create overheating runaway conditions, particularly in non-monitored circuits. The capacitors then fail, usually resulting in severe damage. As Fuseac intervenes when things get too hot, the capacitors do not have to heal themselves very often.

Displays go public and private

NEC LCD Technologies of Japan had a breakthrough with the development of its color TFT-LCD module, in which the viewing angle is switchable from wide to narrow to accommodate content and the particular application.

Paired with the company’s TFT-LCD (VIT) technology, the display integrates a viewangle switching control on the polarizer next to the backlight system. The control allows light from the backlight to be switched from a diffused to a straight pattern via control signals.

With the mass proliferation of ATMs, ticketing machines, automatic processing equipment, and public-information displays, the versatile LCD addresses two concerns: security and high visibility. In the case of ATMs where privacy is required, setting a narrow view angle will thwart prying eyes. For publicinfo consoles, the wider angle allows everyone to see.

Component market trends
According to Frost & Sullivan, the demand for isolation transformers will grow due to the vast global expansion of commercial and industrial infrastructure. Commercial and medical transformers also will see significant demand, particularly in the U.S.

This analysis is based on growth in the construction industry and emerging energy-efficiency specifications from UL, the CSA, and NEMA. Ongoing commercial and industrial development in Asia is fueling the demand for the components as well. The analysts concur that the isolation-transformer market earned revenues of $641 million in 2006 with a growth rate of 1.7%. This upswing, though, is not without concerns. “Given the simple construction of the product and lack of significant technology innovation or product differentiation, isolation transformers are considered a commodity,” says research analyst Ajay Kumar Sridharan. “In this situation, emphasis on competitive prices will be a unique selling point for vendors.”

The generic nature of the components, paired with increasing prices and a lack of raw materials, creates price pressure on vendors. Also, the replacement of isolation transformers with double-conversion technology in uninterruptible power supplies could have a reverse effect on market demand.

The researchers say vendors should use aluminum to replace copper to address materials shortages. Vendors also should target growing application markets and regions that offer a potential for business development, i.e., focusing on the Asian market.

Who's hot in displays
Research firm DisplaySearch recently released its Quarterly North America Industrial Report, debuting as the industry’s first report covering display shipment data from overseas manufacturers and distributors to industrial manufacturers in North America. The report covers shipments for six display manufacturers to their OEMs and distributors as well as shipments for four distributors. Applications include industrial, industrial mobile, information, instrumentation, kiosk, and medical displays. Sharp was the leading display manufacturer in the industrial display category with a 54.5% market share, followed by NEC and Optrex America (see the table). For distributor shipments, Avnet came in first with a 44.5% market share, with Bell Microproducts and Dynamic Image Technologies as runners up.

Meanwhile, Insight Media analysts attending the Custom Electronic Design & Installation Association (CEDIA) trade show last September in Japan came back with a look at emerging trends in the home-theater markets. Attendees believed 1080p displays are the dominant market force in flat-panel displays, while some saw more growth left for 720p products. There’s also lukewarm interest for 120-Hz or extended color gamut technologies.