SGM864S

The SGM864S is an integrated, 4-rail power sequencer. It controls the power-up and power-down sequence of four power supplies by pulling their enable or shutdown pins high or low. Staggered start sequence can avoid the impact of latch conditions or large inrush current on system reliability. 

The device has five open-drain outputs that are controled by five enable pins. When the EN pin is pulled high and the ENx pin is high, each of the four outputs (OUT1 to OUT4) is released after a fixed delay time, which can be adjusted by the NP0 capacitor outside the CDLYx pin. When EN remains high and any ENx is pulled low, the OUTx will be shut down correspondingly. When ENx remains high and EN is pulled low, the outputs are pulled low in reverse order (from OUT4 to OUT1) after CDLY programmable delay time. If the four OUTx all output high, the PG pin outputs high. 

The SGM864S also includes an internal clamp voltage regulator that stabilizes the internal reference voltage at 5V with an accuracy of ±2.6% by using shunt resistors (RSHUNT) on VCC. The maximum external supply voltage (VDD) is 22V. The total value of the capacitor (CIN) pulled down to GND should be limited to between 1µF and 10µF. When VCC is 2V to 5.5V, set EN_REF to high or connect it to VCC, then the shunt voltage reference is disabled. VCC does not require any external resistor. Once VCC rises above 6V, the shunt voltage reference is enabled. Set EN_REF to low or keep it floating (a 500kΩ built-in resistor). VCC requires the shunt resistors of 130Ω to 40kΩ. 

The SGM864S is available in a Green TQFN-3.5×3.5-20L package. It operates over a junction temperature range of -40℃ to +125℃.