Peak-program-detector

17,801

Peak-program-detector
Peak-program-detector

This circuit enables a multimeter to display the positive or negative peaks of an incoming signal. A 741 operational amplifier, designated as IC1, is configured in non-inverting mode with resistor R1 establishing the input impedance. Diodes D1 and D2 conduct during positive or negative peaks, respectively, charging capacitor C2 until the inverting input reaches the same voltage level as the incoming peak. This voltage level is maintained until a higher peak is detected, at which point it is stored by C2. Another 741 operational amplifier, referred to as IC2, functions to prevent loading by the multimeter. Additionally, IC2 is connected in non-inverting mode as a unity gain buffer, resulting in an output impedance of less than 1 ohm. The circuit exhibits a useful frequency response from 10 Hz to 100 kHz within ±1 dB. High linearity is achieved by placing the diodes in the feedback loop of IC1, effectively compensating for the 0.6 V bias required by these components.

The described circuit utilizes two operational amplifiers (op-amps) to capture and hold the peak values of an incoming signal. The first op-amp (IC1) is configured in a non-inverting configuration, which allows for high input impedance and minimal loading on the signal source. The resistor R1 is selected based on the desired input impedance, ensuring that the circuit can interface with a variety of signal sources without significant signal degradation.

Diodes D1 and D2 are strategically placed to allow for the detection of both positive and negative peaks. When a peak occurs, the corresponding diode conducts, allowing capacitor C2 to charge to the peak voltage. This capacitor acts as a sample-and-hold element, maintaining the voltage level until a new peak occurs. The design ensures that the voltage across C2 only updates when a higher peak is detected, providing a reliable representation of the signal's peak values.

The second op-amp (IC2) is configured as a unity gain buffer, which isolates the capacitor from the measurement device, in this case, a multimeter. This buffering is crucial as it prevents any loading effects that could alter the voltage reading on the multimeter, ensuring accurate peak measurements. The low output impedance of less than 1 ohm allows for effective interfacing with various measurement instruments.

The frequency response of the circuit, spanning from 10 Hz to 100 kHz at ±1 dB, indicates that it is well-suited for a wide range of signal frequencies. The linearity of the circuit is enhanced by the feedback configuration that incorporates the diodes, which compensates for the inherent forward voltage drop (approximately 0.6 V) of the diodes. This careful consideration in design allows for accurate peak detection across the specified frequency range, making the circuit robust for various applications in signal processing and measurement.This circuit will allow a multimeter to display the positive or negative peaks of an incoming signal. A 741, JC1, is used in the noninverting mode with R1 defining the input impedance. D1 or D2 will conduct on a positive or negative peak, charging C2 until the inverting input is at the same de level as the incoming peak.

This level will maintain the voltage until a higher peak is detected, then this will be stored by C2. Another 7 41, IC2, prevents loading by the multimeter. Connected in the noninverting mode as a unity gain buffer, output impedance is less than 1 !l. This circuit has a useful frequency response from 10Hz to 100 kHz at ±1 dB. High linearity is ensured by placing the diodes in the feedback loop of JC1, effectively compensating for the 0.6 V bias that these components require.