Nanosecond Peak Detect and Hold Circuit With Adjustable Dynamic Range.

This article presents a novel peak detect and hold (PDH) circuit for the measurement of the peak voltage of electromagnetic-field probes. These probes are used to capture the fields generated by electrostatic discharge (ESD) events in nongrounded portable devices. Therefore, a circuit combining small size, low power consumption, and nanosecond operation is needed. A topology using a discrete bipolar transistor structure with operational transconductance amplifier (OTA) and common-base storage capacitor charge control optimally meets the requirements. The circuit performance is demonstrated for different bias point settings. The error between the captured value and the actual pulse peak value is shown as a function of rise time, pulselength, amplitude, and bias settings. A comparison with the literature shows unmatched performance with respect to speed and power consumption. Using the bias settings, the PDH circuit can be adjusted to the sensor's frequency response to minimize power consumption in a multichannel system containing sensors of different bandwidths.