SLVSCG3F January 2014 – July 2017 TPS22968
The TPS22968 is a 5.5-V, 4-A, dual-channel ultra-low RON load switch with controlled turnon. The device contains two N-channel MOSFETs. Each channel can support a maximum continuous current of 4 A and is controlled by an on and off GPIO-compatible input. The ON pin must be connected and cannot be left floating. The device is designed to control the turnon rate and therefore the inrush current. By controlling the inrush current, power supply sag can be reduced during turnon. The slew rate for each channel is set by connecting a capacitor to GND on the CT pins.
The slew rate is proportional to the capacitor on the CT pin. See the Adjustable Rise Time section to determine the correct CT value for a desired rise time.
The internal circuitry is powered by the VBIAS pin, which supports voltages from 2.5 V to 5.5 V. This circuitry includes the charge pump, QOD (optional), and control logic. For these internal blocks to function correctly, a voltage between 2.5 V and 5.5 V must be supplied to VBIAS.
When a voltage is supplied to VBIAS, the ON1 pin goes low, and the ON2 pins go low, the QOD turns on. This connects VOUT1 and VOUT2 to GND through an on-chip resistor. The typical pulldown resistance (RPD) is