Datasheet

ADP194 Data Sheet
Rev. A | Page 8 of 12
THEORY OF OPERATION
The ADP194 is a high-side PMOS load switch. It is designed to
operate from a supply range from 1.1 V to 3.6 V. The PMOS load
switch is designed for low on resistance, 80 mΩ at V
IN
= 1.8 V,
and supports 500 mA of continuous output current. The ADP194
is a low ground current device with a nominal 4 MΩ pull-down
resistor on its enable pin.
The reverse current protection circuitry prevents current flow
backwards through the ADP194 when the output voltage is
greater than the input voltage. A comparator senses the differ-
ence between the input and output voltages. When the difference
between the input voltage and output voltage exceeds 50 mV,
the body of the PFET is switched to V
OUT
and turned off or
opened. In other words, the gate is connected to VOUT.
The package is a space-saving 0.8 mm × 0.8 mm, 4-ball WLCSP.
08629-115
GND
EN
VIN
VOUT
ADP194
LEVEL SHIFT
AND SLEW
RATE CONTROL
REVERSE
POLARITY
PROTECTION
Figure 15. Functional Block Diagram