H-bridge driving circuit

Abstract

The invention provides an H-bridge driving circuit. The circuit is characterized by comprising the following steps that: a photoelectric isolating circuit converts a received first pulse width modulation (PWM) signal into a second PWM signal and transmits the second PWM signal to a dead zone control logic module; the dead zone control logic module sets dead zone information according to the second PWM signal, and generates an upper bridge arm control signal and a lower bridge arm control signal according to the dead zone information and the second PWM signal, and the dead zone control logic module transmits the upper bridge arm control signal to an upper bridge arm front driving circuit and transmits the lower bridge arm control signal to a lower bridge arm front driving circuit; and the upper bridge arm front driving circuit and the lower bridge arm front driving circuit control the operation state alternation of a load driving circuit according to the upper bridge arm control signal and the lower bridge arm control signal respectively. The circuit can avoid the capacity effect in the voltage change process of an H-bridge circuit load unit and the output frequency of the H-bridge driving circuit can be increased.

Description

technical field [0001] The present application relates to the technical field of drive circuits, in particular to an H-bridge drive circuit. Background technique [0002] The H-bridge drive circuit is a typical DC motor control circuit. The H-bridge motor drive circuit includes 4 triodes and a motor. To make the motor run, a pair of triodes on the diagonal must be turned on. Depending on the conduction of different transistor pairs, current may flow through the motor from left to right or from right to left, thereby controlling the direction of rotation of the motor. [0003] In practical applications, the H-bridge drive circuit usually uses PWM (Pulse Width Modulation) mode for low-power DC drive. It is widely used because of its simple structure, high efficiency and low cost. The H-bridge drive circuit generally uses 4 MOS tubes as the drive chip to form the 4 bridge arms of the H-bridge. At present, the H-bridge integrated circuit drive method is widely used, that is,...

AI Technical Summary

Problems solved by technology

The capacity of the capacitive effect generally ranges from hundreds of PF to thousands of PF. The existence of junction capacitance delays the rise and fall time of the gate drive voltage of the MOS transistor, thus hindering the increase of the output frequency of the H-bridge drive circuit.

Images