Electronic Circuits and electronic circuits, electronic schematics plus an extensive resource for hobbyists, inventors and engineers

DiscoverCircuits.com, has 45,000+ electronic circuits, cross-referenced
into 500+ categories.    We have searched the web to help you find quick design ideas.
We make every effort to link to original material posted by the designer. 
Please let us if you would like us to link to or post your design.

HOME Schematics Index Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches



Comparator Circuits

Comparators:  #B        C       D - K       L - S       T - Z

 

Last Updated: December 31, 2017 06:47 AM

Circuits Designed by Dave Johnson, P.E.

12v Cooling Fan Thermostat This circuit will turn on a 12v DC powered cooling fan when the air temperature reaches a certain high temperature and will keep the fan turned on until the temperature drops below a second lower level.  Both the high and low temperatures are both adjustable. . . Circuit by David Johnson P.E.-February, 2011

1us Light Pulse Discriminator This circuit is designed to detect the narrow 1uS pulses produced by the above amplifier circuit.  The clean logic type pulses produced by the discriminator are then sent to a frequency to voltage converter.  The circuit is designed to process a pulse frequency . . . Hobby Circuit designed by David A. Johnson P.E.-March, 1999

40Khz Ultrasound Receiver A X100 transistor amplifier is followed by a zero cross detector circuit, using a voltage comparator.  The output is a TTL logic signal, corresponding to the received 40KHz signal. . . Circuit by David Johnson P.E.-January, 2006

AC Peak Detector that is Precise This unique circuit uses a very inexpensive voltage comparator to form a peak detector.  The DC voltage produced tracks the positive peak of the input signal.  It works from about ten millivolts to about 10 volts peak to peak.  The maximum frequency is about . . . Hobby Circuit designed by David Johnson P.E.-February, 2002

Acceptable Voltage Indictor I have used this circuit many times in custom test fixtures where a simple go-no go indication was needed.  The circuit can also be used to adjust a particular voltage be within specific high or low limits.  The three LEDs will indicate if the voltage is. . . Circuit by David Johnson P.E.-February, 2002

Amplifier for a Xenon Lamp Flash Detector This circuit has a very low standby current requirement yet has very high sensitivity toward the light flashes from a xenon lamp.  When connected to a flip/flop it can serve as an on on/off Controller. . . Circuit by David Johnson P.E.-February, 2002

Battery Charge Current Indicator This circuit turns on a LED whenever it detects at least 25ma of battery charge current. . . Circuit by David Johnson P.E.-July, 2006


Links to electronic circuits, electronic schematics, designs for engineers, hobbyists, students & inventors:

1us Light Pulse Discriminator This circuit is designed to detect the narrow 1uS pulses produced by the above amplifier circuit.  The clean logic type pulses produced by the discriminator are then sent to a frequency to voltage converter.  The circuit is designed to process a pulse frequency . . . Hobby Circuit designed by David A. Johnson P.E.-March, 1999

12v Cooling Fan Thermostat This circuit will turn on a 12v DC powered cooling fan when the air temperature reaches a certain high temperature and will keep the fan turned on until the temperature drops below a second lower level.  Both the high and low temperatures are both adjustable. . . Circuit by David Johnson P.E.-February, 2011

2 buttons provide safe start 07/06/00 EDN-Design Ideas The circuit in Figure 1 provIdeas a safety interlock that checks the actuation of two pushbuttons before enabling a relay.  When you push both buttons, the circuit actuates the relay.  At that point, you can release one of the switches without the relay'__ Circuit Design by   Vincent Himpe, Alcatel Microelectronics, Desselgem, Belgium

2-Wire Thermistor 0°C to 100°C Temperature Transducer with 4mA to 20mA Output The LTC1040 is a monolithic CMOS dual comparator manufactured using Linear Technology’s enhanced LTCMOS TM silicon gate process.  Extremely low operating power levels are achieved by internally switching the comparator ON for short periods of time.  The CMOS output logic holds the output information continuously while not consuming __ Linear Technology/Analog Devices App Note, Mar 30th 2010

40Khz Ultrasound Receiver A X100 transistor amplifier is followed by a zero cross detector circuit, using a voltage comparator.  The output is a TTL logic signal, corresponding to the received 40KHz signal. . . Circuit by David Johnson P.E.-January, 2006

5V Powered Thermistor Heating/Cooling Automatic Thermostat The LTC1040 is a monolithic CMOS dual comparator manufactured using Linear Technology’s enhanced LTCMOS TM silicon gate process.  Extremely low operating power levels are achieved by internally switching the comparator ON for short periods of time.  The CMOS output logic holds the output information continuously while not consuming __ Linear Technology/Analog Devices App Note, Mar 30th 2010

A Seven-Nanosecond Comparator for Single Supply Operation Linear Technology AN72 __ Designed by Jim WilliamsMay 1st, 1998

Absolute Value (Full-Wave Rectifier) For negative inputs, the first section operates as a closed-loop inverter   (A=-1) and the second stage is simply a buffer for the positive output.  When the input signal is positive, the first opamp output remains saturated near ground and the diode becomes high-impedance, allowing the signal to pass directly to the buffer stage non inverted.  The composite effect is a full-wave rectified waveform at the output of the buffer. __ Linear Technology/Analog Devices App Note, Jun 21, 2011

Absolute-value comparator touts accuracy, size 03/07/02  EDN-Design Ideas A typical window comparator uses two comparators and a single op amp to determine whether a voltage is inside or outside a boundary region.  Figure 1 shows a typical implementation.  IC1 is an inverting op amp with a gain of –1.  VREF and –VREF create the wi__ Circuit Design by Teno Cipri, Engineering Expressions Consulting, Sunnyvale, CAEDN Design Idea March 7, 2002

Absolute-Value Delivers High Bandwidth 15-May-03 EDN-Design Ideas Most absolute-value circuits have limited bandwidth and high component count, and they require several matched resistors.  The circuit in Figure 1 uses three fewer components than most absolute-value circuits require, and only two of the resistors must have 1% tolerance to obtain 1% accuracy.  This circuit's output voltage is an accurate representation of the absolute value of the input signal,__ Circuit Design by Ron Mancini, Texas Instruments, Bushnell, FL

AC Peak Detector that is Precise This unique circuit uses a very inexpensive voltage comparator to form a peak detector.  The DC voltage produced tracks the positive peak of the input signal.  It works from about ten millivolts to about 10 volts peak to peak.  The maximum frequency is about . . . Hobby Circuit designed by David Johnson P.E.-February, 2002

Acceptable Voltage Indictor I have used this circuit many times in custom test fixtures where a simple go-no go indication was needed.  The circuit can also be used to adjust a particular voltage be within specific high or low limits.  The three LEDs will indicate if the voltage is. . . Circuit by David Johnson P.E.-February, 2002

Add Hysteresis to a Voltage Comparator 4-Mar-10 EDN-Design Ideas Positive feedback is a typical technique for distributing hysteresis around a comparator, provided that you have a resistive path between the comparator's output and the noninverting input.  Positive feedback forms two threshold voltages that have  (or assume] fixed values.  In addition, they depend on the saturation values of the comparator's output stage__ Circuit Design by Luca Bruno, ITIS Hensemberger Monza, Lissone, Italy

Amplifier for a Xenon Lamp Flash Detector This circuit has a very low standby current requirement yet has very high sensitivity toward the light flashes from a xenon lamp.  When connected to a flip/flop it can serve as an on on/off Controller. . . Circuit by David Johnson P.E.-February, 2002

AN13High Speed Comparator Techniques Linear Technology AN13 __ Designed by Jim WilliamsApr 1st, 1985

AN72A Seven-Nanosecond Comparator for Single Supply Operation Linear Technology AN72 __ Designed by Jim WilliamsMay 1st, 1998

Analog comparator recognizes three signal relations 07/23/13  EDN-Design Ideas Several years ago we were developing a clamp-on photometer, a hand-held instrument that could be clamped onto a communications optical fiber to indicate the presence of light, its direction of travel, and the presence of combinations of low-frequency test tone modulation.  Its purpose was to positively identify a particular__ Circuit Design by Glen Chenier

Analog Comparison, Digital Result  Comparators are very useful for comparing two analog voltages and providing a digital result.  In this case, if the light source is dim, a red LED is enabled.  If the light source is bright, a green LED is enabled.  However, once comparators are understood, they can be useful for driving small robots or helping a microcontroller. __ Contact: David Cook

Battery Charge Current Indicator This circuit turns on a LED whenever it detects at least 25ma of battery charge current. . . Circuit by David Johnson P.E.-July, 2006


Comparators:  #B        C       D - K       L - S       T - Z


HOME Schematics Index Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches


 About Us   |  Advertise on DiscoverCircuits.com   |   Report Broken Links  |    Link to DiscoverCircuits.com  |    Privacy Policy


Copyright  January, 1998 - December, 2017     David A. Johnson & Associates.  All Rights reserved. 


 Linking is ALLOWED but COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED.