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Micro-power Band-pass Network - Circuit ideas for Designers App Note__ Advanced Linear Devices, Inc
Micropower CMOS
Oscillator, Draws Only 0.5ua - if truly low power oscillators interest you, this circuit draws a mere 2 microwatts (500nA) from a 6v battery. it uses a very inexpensive C-MOS IC to produce a frequency of 2Hz. However, by changing the component values you can push it to 300Hz. . . Circuit by Dave Johnson P.E.-June, 2000
Microprocessor generates programmable clock sequences - 05/12/05 EDN Design Ideas: imulate radar and sonar returns with simple circuit Design by William Grill, Honeywell BRGA, Lenexa, KS
Miniature Pushbutton On/Off Switch - in many battery powered devices, you would like to turn the circuit on and off by pressing a small pushbutton switch. One press turns the device on and second press turns it back off. The flip/flop circuit below uses a minimum number of parts to perform . . . Hobby Circuit designed by David Johnson P.E.-October, 2005
Minimize the Short-Circuit Current Pulse in a Hot-Swap Controller - 27-May-04 EDN Design Ideas: Because of internal circuit-breaker delay and limited MOS-gate pulldown current, many hot-swap controllers do not limit current during the first 10 to 50 µsec following a shorted output. The result can be a brief flow of several hundred amperes. A simple external circuit can counter this problem by minimizing the initial current spike and terminating the short circuit within 200 to 500 nsec Design by Jim Sherwin and Thong Huynh, Maxim Integrated Products, Sunnyvale, CA
Model Train Horn (2-tone) - With this circuit you can electronically simulate the noise of a diesel-train horn. The sound is triggered automatically as the train reaches a desired place on the track so you can produce the sound as the train approaches stations, level crossings, etc. The circuit can be built simply by using one 556 or two 555 timers __ Designed by Tony van Roon VA3AVR
Monostable Flip Flops (One Shot) - The two circuits below illustrate using the 555 timer to close a relay for a predetermined amount of time by pressing a momentary N/O push button. The circuit on the left can be used for long time periods where the push button can be pressed and released before the end of the timing period. For shorter periods __ Designed by Bill Bowden
Motorized Duck Decoy Timer - I received a nice email from a duck hunter. He uses some motorized decoys to lure ducks into his line of fire. However, the battery powered decoys only have an on/off switch so once turned on; the decoy flaps its wings or paddles around continuously. The hunter wanted a more realistic motion, which would power the motor for say 10 seconds, then stop for another 10 seconds before starting up again. The simple circuit below should work well for his application . . . Hobby Circuit designed by David A. Johnson P.E.-September, 2011
Multiple Pulse Generator - I used this circuit to ring my doorbell rapidly three times when a car pulled into my driveway. R2 and C2 set the output frequency. Use a diode and resistor to change the duty cycle, if desired. R1 and C1 set the cycle time which sets the number of pulse __ Designed by Andrew R. Morris
NanoPower LC Colpitts Oscillators - Circuit ideas for Designers App Note__ Advanced Linear Devices, Inc
Nanosecond-Width Pulse Generator Provides High Performance - 11/11/04 EDN Design Ideas: if you need to produce extremely fast pulses in response to an input and trigger, such as for sampling applications, the predictably programmable short-time-interval generator has broad uses. The circuit of Figure 1, built around a quad high-speed compara Design Jim Williams, Linear Technology Corp
Negative-To-Negative Switch-Mode Converter Offers High Current & High Efficiency - 11/12/09 EDN Design Ideas: Don't let variations in input voltage affect the output voltage Design by Budge Ing, Maxim Integrated Products Inc, Sunnyvale, CA
NTSC Test Signal Generator - An accurate test signal generator for television calibration and measurements. __ Designed by The Electronic Lives Manufacturing-presented Chan
On/Off Flip/Flop Circuit with Automatic Timeout - This circuit is ideal when a device needs to be turned on and off with a single pushbutton switch, but also needs to turn itself off after some period of time. With the components shown, the output will stay on for only about 20 seconds. . . Circuit by Dave Johnson P.E.-May, 2012
One Hz Pulse Frequency Generator - Here is a 1Hz pulse/frequency generator using the popular timer IC 555 which is wired as an Astable Multivibrator. The output pulses can be indicated visually by the LED. An Astable Multivibrator, often called a free-running Multivibrator, is a rectangular-wave generating circuit. Unlike the Monostable Multivibrator, this __ Designed by D Mohankumar
One IC 2 Tones Siren Double Tone Police Sound Single Tone Old AM bulance Sound - This circuit is intended for children fun, and is suitable to be installed on bicycles, battery powered cars and motorcycles, but also in models and other games. With SW1 positioned as shown in the circuit diagram it reproduces the typical dual tone sound of Police __ Contact Flavio Dellepiane, fladello @ tin.it
One Second Time Base from Crystal Oscillator - The schematic above illustrates dividing a crystal oscillator signal by the crystal frequency to obtain an accurate (0.01%) 1 second time base. Two cascaded 12 stage counters (CD4040) form a 24 stage binary counter and the appropriate bits are gated together to produce the desired division. Using a crystal of some even multiple of 2 is desirable so that one stage of the counter automatically toggles every second which eliminates the need for the NAND gate and reset circuitry, however the circuit below illustrates using a crystal which is not an even multiple of 2 and so requires additional __ Designed by Bill Bowden
One Shot (D-Flip/Flop) Circuit - Yes you can use cheap D flip/flop logic circuits as nice one-shot pulse generators. This schematic shows how the popular CD4013 and the CD74HC74 can be used to generate pulses ranging from nanoseconds to seconds. . . Circuit by David A. Johnson P.E.-June, 2000
Oneshot & Latch Pushbutton - This circuit uses a single IC to convert a noisy pushbutton switch signal into a clean pulse or a sustained push on-push off signal. it can operate from 3v to 18v . . . Hobby Circuit designed by David Johnson P.E.-March, 2002
Op Amp as a Set/Reset Flip-Flop - 05/24/12 EDN Design Ideas: Eliminate a flip-flop package by using a spare op amp for an SR latch function. You can make a set/reset flip-flop from two NAND or NOR gates or use readily available set/reset flip-flop IC s, such as the 74HC279 quad-set/reset latch. The drawback of these methods is that they require a large amount of space to form the flip-flop. Even if you need only one flip-flop, you must use a large IC package with this approach. However, you can use a spare rail-to-rail op amp to perform the needed latch function (Figure 1). Design by Aruna Rubasinghe
Op Amp Triangle-Wave Generator & SPICE simulation files - This signal generator gives you two waveforms for the price of one: a triangle-wave and a square-wave. What is the central component of this circuit? The integrator capacitor Ci__
Op-Amp Oscillators Simplify RF Design - 10/10/96 EDN Design Ideas: Figure 1 shows a novel circuit that uses a low-cost, high-speed op amp as a crystal-controlled RF sine-wave oscillator. An op-amp oscillator offers several advantages. Because an op amp is a complete amplifier with a high-impedance input Design by Charles Kitchin, Analog Devices, Wilmington, MA
Oscillator Draws 2 Nanoamps - if you have hundreds of touch switches that need an excitation signal, then this circuit is what you need. its 20KHz 20v peak to peak output signal can supply up to 3 watts of touch switch excitation power . . . Hobby Circuit designed by David Johnson P.E.-July, 2006
Oscillator keeps THD BeLow One PPM - 11/10/94 EDN Design Ideas: The Wien-bridge sine-wave oscillator uses a light bulb to stabilize its amplitude. The circuit doesn't have a light bulb; it sports several enhancements that lower its distortion Design by Jeff Smith, Analog Devices, Wilmington, MA
Oscillator Lowers Distortion & Phase Noise - 08/18/94 EDN Design Ideas: in addition to its normal role of controlling oscillation frequency, the crystal in Fig 1 also acts as a high-Q, self-tuned output filter, which rejects the noise and harmonics of its input voltage, VB. The result is a clean output-frequency spectrum. With a Design by Giovanni Stochino, Ericsson Telecommunicazioni Spa, Rome Italy
Oscillator phase noise - Phase noise serves as an important oscillator parameter and some amateur radio enthusiasts seem confused about what it is, how it’s measured, and most importantly, how it might affect what they’re working on __ Contact Vasily Ivanenko
Oscillator Sawtooth & Square Wave Output - Simple, Single Supply and Works Very well with Minimum Parts Count. __ Designed by G.L. Chemelec
Oscillator Turns On Instantly, Off Synchronously - 05/23/96 EDN Design Ideas: The oscillator in Figure 1 has several desirable features. You can adjust the oscillator frequency from approximately 500 kHz to 4 MHz, it is fairly stable for an RC type, and it uses inexpensive standard components. Also, you can easily control the oscillator Design by Raymond Scott, SOR Inc, Lenexa, KS
Oscillator Uses Dual-Output Current-Controlled Conveyors - 13-Nov-08 EDN Design Ideas: Varying the bias current of dual-output current-controlled conveyors controls the frequency of oscillation of the circuits Design by Abhirup Lahiri, Netaji Subhas Institute of Technology, New Delhi, India
Oscillator with Ultra Low Current - Here is a challenge. Design an astable oscillator which draws only a few nanoamps of current from a +3v supply. I gave this some thought and came up with the circuit below. I used some pretty standard parts except for three surface mounted 1000M resist . . . Hobby Circuit designed by David A. Johnson P.E.-March, 2009
Over-Temperature Micro-Power Alarm - The circuit is powered for years by a single 3 volt lithium battery. it sounds an alarm when the temperature exceeds a certain point. With some minor changes the circuit could also be configured for an under temperature (freeze) alarm. The circuit uses a . . . Hobby Circuit designed by David Johnson P.E.-June, 2000 |
