Other Parts Discussed in Thread: SN74LVCR2245
SN74LVCR2245A used as a buffer in my circuit, Signal defined form B to A, DIR pin and OE pin tied to GND
Power Pin tie to VCC3V3_A power rail
system power up, SN74LVCR2245A Port A side signal power up first, current backflow function is OK, partial-power-down is OK. VCC3V3_A is 0 V, when system open VCC3V3_A power rail, SN74LVCR2245A Port A side and controller power up, signal form Port B to Port A is OK
But ! when system close VCC3V3_A power rail,SN74LVCR2245A Port B side and the controller power off, I test VCC3V3_A Voltage is about 1V voltage in the power pin,
So,why do the partial-power-down do not function? is this current backflow from A side to B side?