TW200709543A - Reliable bi-directional driving circuit for wide supply voltage and output range - Google Patents

Abstract

The present invention provides a bi-directional driving circuit for wide supply voltage and output range, which includes a power supply voltage, a bridge circuit containing a first switch, a second switch, a third switch and a fourth switch, in which the power supply voltage provides the power supply, the first, second, third and fourth switches are electrically connected to form two vertical arms respectively each having a first output terminal and a second output terminal, and the first output terminal and the second output terminal are electrically connected with a load; a first power controller containing an output terminal electrically connected with an input terminal of the first switch; a second power controller containing an output terminal electrically connected with an input terminal of the second switch; a third power controller containing an output terminal electrically connected with an input terminal of the third switch; a fourth power controller containing an output terminal electrically connected with an input terminal of the fourth switch; a first loopback network electrically connected with a differential amplifier and a second differential amplifier; a second loopback network containing a control voltage electrically connected therewith and electrically connected with the first differential amplifier, the second differential amplifier and the first output terminal of the bridge circuit; a third loopback network electrically connected with a third differential amplifier, a fourth differential amplifier, and the first output terminal and second output terminal of the bridge circuit; and a fourth loopback network electrically connected with the third differential amplifier and the fourth differential amplifier. A current that flows through the load is substantially independent of the power supply voltage and is proportional to the control voltage.