Design of a under voltage lock out circuit with bandgap structure

According to the necessary function of under voltage lock out (UVLO) in DC-DC power management systems, an improved UVLO circuit is proposed. The circuit realizes stabilization of parameters such as threshold point voltage, hysteretic range of the comparator etc. without utilizing an extra bandgap reference voltage source for comparison. The UVLO circuit is implemented in CSMC 0.5¿m BCD process. Hspice simulation results show that the UVLO circuit presents advantages such as simple topology, sensitive response, low temperature draft, low power consumption.