PS12

www.DataSheet4U.com PS12 Quad Power Sequencing Controller Features ► Power supply sequencer with four outputs ► Power-up and power-down sequencing ► Six programmable delays ► Maximum 90V supply voltage ► Input voltage window comparator ► Low power supply current (500µA typical) ► 16-Lead SOIC Package General Description Many systems require that their power supplies are enabled and disabled sequentially in order to reduce transient current demand on the power bus, or to avoid damage to components having multiple supply voltages such as microprocessors, ASICs, MEMS drivers, etc. The PS12 incorporates a power-up delay timer, a window voltage comparator, 4 open drain enable outputs, and 6 enable delay timers. The enable delays are individually programmable for both the power-up (ABCD) and the powerdown (DCBA) sequence. Power-up and power-down are controlled by a window comparator formed by the ON and OV voltage comparators. VIN voltage within the window initiates power-up; VIN voltage outside of the window maintains or initiates power-down. The power-up sequence may be interrupted while in progress. The power-down sequence, once initiated, cannot be interrupted until it is brought to completion. Applications ► Reduction of transient current demand and protection of sensitive loads ► Telecom and networking systems ► High voltage MEMS and display driver supplies Typical Application Circuit +12V 15 R1 3 VIN ON 1 VEE PSA 11 ENA +12V CONVERTER OUT R2 4 OV PSB 12 ENA R3 ...