Data Sheet

ADP1196

Rev. 0 | Page 9 of 12

THEORY OF OPERATION

Figure 21. Functional Block Diagram

The ADP1196 is a high-side or low-side N-channel metal oxide

semiconductor (NMOS) load switch that is controlled by an

internal charge pump. The ADP1196 operates with voltages

from 1.83 V to 5.5 V on either VIN or VB_EN.

Internal circuitry monitors the VIN and VB_EN pins, connecting

the internal power supply to the higher of the two voltages. This

operation allows the NMOS load switch to operate on the low

side of a particular load.

An internal charge pump biases the NMOS switch to achieve a

relatively constant, ultralow on resistance of 10 mΩ across the

entire supply range. The use of the internal charge pump also

allows for controlled turn-on times. Turning the NMOS switch

on and off is controlled by the enable input, VB_EN, which can

interface directly with 1.83 V logic signals when VIN is greater

than 1.8 V.

less than or equal to 70°C. At 85°C, the derated load current falls to

±2.22 A. Overcurrent protection limits the output current to 4 A.

The overtemperature protection circuit is activated if the load

current causes the junction temperature to exceed 125°C. When

this occurs, the overtemperature protection circuitry disables the

output until the junction temperature falls below approximately

110°C, at which point the output is reenabled. If the fault condition

persists, the output cycles off and on until the fault is removed.

ESD protection structures are shown in the block diagram as

Zener diodes (see Figure 21).

The ADP1196 is a low quiescent current device with a nominal

4 MΩ pull-down resistor on its enable pin (VB_EN). The package

is a space-saving 1.0 mm × 1.5 mm, 6-ball WLCSP.

VOUT

VIN

VOUT

VIN

GND

VB_EN

CHARGE PUMP,

OVERCURRENT,

AND SLEW RATE

CONTROL

OVERTEMPERATURE

PROTECTION

SUPPLY SWITCH

ENABLE LOGIC