Circuit and method of current limiting a half-bridge driver

摘要

A half-bridge driver provides a current limit on the low-side driver (20) and a current limit on the high-side driver (16). The current limits are initially set equal. If the low-side driver current limits, then a modulation current from the low-side driver increases the high-side driver current limit threshold to maintain stable operation of the control circuits. In addition, the present invention provides dual conduction paths to charge the main conduction transistor of the low-side driver, while detecting current limit. When current limit is detected, the charging current to the main conduction transistor is switched to current limit mode.