Discriminator Electronic Circuits

Discriminator Circuits
Last Updated on: Friday, March 12, 2010 12:07 PM

Circuits Designed by Dave Johnson, P.E. :

1uS LIGHT PULSE DISCRIMINATOR PLUS F TO V CONVERTER
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 of 10KHz that is frequency modulated by voice audio signals. The circuit is described in more detail in the receiver circuit section of my Handbook of Optical Through the Air Communications. Note: Since the MF6-50 switched capacitor filter IC is no longer available; this circuit is for reference only. Use circuit number xyz in place of the IC filter.

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

1us Light Pulse Discriminator Plus F to V Converter - 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 of 10KHz that is frequency modulated by voice audio signals. The circuit is described in more detail in the receiver circuit section of my Handbook of Optical Through the Air Communications. Note: Since the MF6-50 switched capacitor filter IC is no longer available; this circuit is for reference only. Use circuit number xyz in place of the IC filter. ….(designed by David A. Johnson)

A Seven Nanosecond Comparator for Single Supply Operation - AN72 Linear Technology AN72 is an extensive discussion of causes and cures of problems in very high speed comparator circuits. A separate applications section uses 7ns LT1394 in V-to-F converters, crystal oscillators, clock skew generators, triggers, sampling configurations and a nanosecond pulse stretcher. Appendices cover related topics.

Absolute Value Circuit Delivers High Bandwidth - 05/15/03 EDN-Design Ideas: Most absolute-value circuits have limited bandwidth and high component count, and y require several matched resistors. The circuit in Figure 1 uses three fewer components than most absolute-value circuits require, and only two of resistors must have 1% tolerance to obtain 1% accuracy. This circuit's output voltage is an accurate representation.....(design idea added 1/05)

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 wher 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 window limits. When VIN becomes more positive than VREF, output of IC2A goes low.....(design idea added 1/05)

An IC Voltage Comparator for High Impedance Circuitry - National Semiconductor Application Note (app note added 2/06)

AN-41: Precision IC Comparator Runs from +5V Logic Supply - National Semiconductor Application Note (app note added 2/06)

AN-87: Comparing the High Speed Comparators - National Semiconductor Application Note (app note added 2/06)

Applications of the LM392 Comparator Opamp Ic - National Semiconductor Application Note 04-Nov-1995 (app note added 4/02)

Circuit Techniques for Avoiding Oscillations in Comparator Applications - National Semiconductor Application Note (app note added 2/06)

Comparator Provides Stable Hysteresis - 03/18/99 EDN-Design Ideas: Unless a voltage-comparator circuitis sampling an extremely clean signal, the comparator always requires some hysteresis. Traditional comparator circuits obtain the required hysteresis by using positive feedback derived from the ratio of two resistors. The voltage at the noninverting input is the superposition.....(design idea added 7/03)

Comparator uses Signal Dependent Hysteresis - 03/26/98 EDN-Design Ideas: A project posed the challenge of replacing existing analog potentiometers (used to set brightness and contrast levels)in video monitors with digitally controlled potentiometers. The different brands and models of monitors presented widely varying voltages across the potentiometers.....(design idea added 03/03/03)

Comparators Form 3 to 5 Volt or 5 to 3 Volt Translator/Tranceiver - 09/02/96 EDN-Design Ideas: In many recent systems, you often need to interface 3V signals with higher voltages within the system. In some cases, it's necessary to interconnect 3 and 5V open-collector transceivers.Figure 1 shows one example, in which multiple multidrop communications devices interconnect. In systems where no control lines are available for interfacing, the.....(design idea added 3/03)

Comparing the High Speed Comparators - National Semiconductor Application Note (app note added 2/06)

Design an Efficient Reset Circuit - 05/01/03 EDN-Design Ideas: When you work with microprocessors, you must ensure that when the power-supply voltage fluctuates to the minimum permissible level, VL, that the processor's ALU continues to operate normally. Also, when you switch on the power supply, the ALU must operate normally when the supply voltage equals or exceeds a certain high level, VH.....(design idea added 1/05)

Design low duty cycle timer circuits - 08/22/02 EDN-Design Ideas: Designing astable circuits using the industry-standard 555 timer is a straightforward process when duty cycles are 50% or greater. However, you must overcome the many pitfalls of low-duty-cycle circuits to arrive at a desired result. Using only ideal components eases the design, but the components themselves are hard to obtain.....(design idea added 1/05)

Electronic fuse emulates fast or slow Blow fuses - 11/09/00 EDN-Design Ideas: The electronic-fuse circuit in Figure 1 combines the properties of a current transducer and a solid-state relay to disconnect low power at preset levels. Using this circuit lets you avoid the bother of stocking and replacing fusible links. The circu.....(design idea added 7/03)

Expanded Scale Indicator Revisited - 08/08/02 EDN-Design Ideas: The visualization aid that a previous Design Idea describes allows only the expansion of the upper end of the scale (Reference 1). But what can you do if, according to your project requirements, you need to expand the middle region of the scale? Figure 1a illustrates the challenge. A voltmeter comprises a 100-µA dc meter and a series resistor.....(design idea added 1/05)

Fast Voltage Comparators with Low Input Current - National Semiconductor Application Notes,28-Jun-1996 (app note added 4/02)

LB-12: Linear Brief 12 an IC Voltage Comparator for High Impedance Circuitry - National Semiconductor Application Note (app note added 2/06)

LB-32: Linear Brief 32 MicroVolt Comparator - National Semiconductor Application Note (app note added 2/06)

LB-39: Linear Brief 39 Circuit Techniques for Avoiding Oscillations in Comparator Applications - National Semiconductor Application Note (app note added 2/06)

LB-6: Fast Voltage Comparators with Low Input Current - National Semiconductor Application Note (app note added 2/06)

Light Sensor With Hysteresis - (Tony van Roon's schematic / circuit added 10/02)

LM139/LM239/LM339 a Quad of Independently Functioning Comparators - National Semiconductor Application Note 24-Feb-1999 (app note added 4/02)

Low Voltage Alarm (Aaron Cake) - NE555 Low Voltage Battery Disconnect Circuit (added 04/03/02)

MicroVolt Comparator - National Semiconductor Application Notes first published 28-Jun-1996/ (app note added 3/03)

Missing Codes Tester Checks 16 Bit ADC in 7 Sec - 06/10/99 EDN-Design Ideas: As the resolution of ADCs increases from 12 to 16 bits and higher, the difficulty in testing the"nomissing-codes"specification grows proportionately. To fully guarantee no missing codes for a 16-bit ADC requires testing all 2 16-1 possible output.....(design idea added 7/03)

Missing Pulse Detector Basic - (Tony van Roon's schematic / circuit added 10/02)

Precision IC Comparator Runs from Plus 5 Volt Logic Supply - National Semiconductor Application Note 04-Nov-1995 (app note added 4/02)

Synchronized Window Comparator Eliminates Error - 05/11/95 EDN-Design Ideas: Precision A/D converters need a window comparator. The window comparator in Fig 1a is synchronized to the clock signal. This synchronization eliminates errors that could arise when the input signal crosses the high or low threshold (Fig 1b)unsynchronized to clock. In operation, comparator IC1A sets flip-flop IC2.....(design idea added 3/03)

Two Buttons Provide Safe Start - 07/06/00 EDN-Design Ideas: The circuit in Figure 1 provides 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'.....(design idea added 7/03)

Voltage Comparator - This experiment only requires a single operational amplifier. The model 1458 and 353 are both "dual" op-amp units, with two complete amplifier circuits housed in the same 8-pin DIP package. I recommend that…(circuit added 6/07)

Voltage Comparator Forms Pulse Demodulator - 11/19/98 EDN-Design Ideas:.....(design idea added 3/03)

Voltage Comparator Switch - This circuit will provide an indication whenever the input voltage differs from two defined limits, V1 and V2. The supply voltage, Vcc must be higher than the highest input voltage by at least 2 volts. One application here is to monitor a 12V car battery.... (electronic diagram added 6/03)