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, pulse length, 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\u27s frequency response to minimize power consumption in a multichannel system containing sensors of different bandwidths

EMC Analysis of the Inverting Boost/Buck Converter Topology

This paper describes the electromagnetic compatibility (EMC) analysis of an inverting buck/boost converter. The inverting buck/boost converter differs from other DC/DC converters, such as the noninverting boost or buck converters, in that one inductor terminal is connected to the ground and not to the input or output of the converter, i.e., neither input nor output is isolated from an EMC perspective. A SPICE model was developed for analyzing the EMC properties of the circuit. Two electromagnetic interference EMI-relevant resonances were observed depending on the state of the switch. Simulations are confirmed with measurements using a circuit designed from discrete components. Further, integrated commercially available converters were analyzed and showed EMC properties that were similar to those of the general model