Patent ID: 8730701
Filing Date: 2014-05-20
Classification: F25B,G05D

Abstract:
1. An electronic circuit for powering a bi-directional load, comprising: an input stage comprising an input terminal connectable to an analog input signal, the input stage providing a control signal based upon the analog input signal, a first reference signal, and a second reference signal, the first reference signal being more positive than the second reference signal, and the input stage being configured such that when the analog input signal is not connected to the input stage, the control signal is between the first and second reference signals; a switch for operatively connecting the analog input signal with the input terminal; a comparator stage operatively connected to the input stage and configured to compare (a) the control signal with the first reference signal producing a first compared signal, and (b) the control signal with the second reference signal producing a second compared signal; and an inverter stage operatively connected to the comparator stage and configured to invert (a) the first compared signal producing a first inverted signal, and (b) the second compared signal producing a second inverted signal; an H-bridge power supply circuit comprising a first switch operatively connected to the comparator stage to be controlled by the first compared signal, a second switch operatively connected to the comparator stage to be controlled by the second compared signal, a third switch operatively connected to the inverter stage to be controlled by the first inverted signal, and a fourth switch operatively connected to the inverter stage to be controlled by the second inverted signal, such that (a) when the control signal is greater than the first reference signal, the H-bridge circuit delivers current to the bi-directional load in a first direction, (b) when the control signal is less than the second reference signal, the H-bridge circuit delivers current to the bi-directional load in a second direction, and (c) when the control signal is between the first and second reference signals, the H-bridge circuit delivers no current to the bi-directional load; and a feedback stage operatively connected with the input stage and configured to provide the analog input signal based upon a feedback signal.