Voltage pulse to current regulating converters.

摘要

A current regulating converter includes a pulse generator (101 which generates a voltage pulse train having a variable duty cycle. A low pass filter (12) is connected to receive the pulse train and has a cutoff frequency which is well below the frequency of the pulse train. The low pass filter (12) generates a dc voltage signal which has a voltage level that is proportional to the duty cycle of the pulse train. The dc signal is used in a circuit (14) that draws a current from a power supply (16). the current being proportional to the voltage level of the dc signal. The power supply (16) is connected to the circuit (14) by a 4-20 mA current loop (18).