1 Features

1• Ultralow Quiescent Current 1 μA (Typical)

at VIN = 1.8 V

• Input Voltage Range: 1.62 V to 5.5 V

• Low ON-Resistance

– r ON = 300 mΩ at VIN = 5.5 V

– rON = 400 mΩ at VIN = 3.3 V

– rON = 500 mΩ at VIN = 2.5 V

– rON = 600 mΩ at VIN = 1.8 V

• Selectable Minimum Current Limit: over155

mA, 70 mA, or 30 mA

• Integrated Inrush Current Time-out (8 ms)

• Shutdown Current: < 1 μA

• Thermal Shutdown

• Fault Blanking

• Auto Restart

• Overcurrent Condition Time-out (Automatic

Disable for Permanent Overcurrent)

• 1.8-V Compatible Control Input

• ESD Performance Tested Per JESD 22

– 6000-V Human-Body Model

(A114-B, Class II)

• Tiny DSGBA Package 1.4 mm × 0.9 mm (YZP)

2 Applications

• Fingerprint Module Protection

• Portable Consumer Electronics

• Mobile Phones

• Smartphones

• Notebooks

• GPS Devices

3 Description

The TPS22946 is an ultralow power load switch that

provides protection to systems and loads in highcurrent

conditions. The device contains a 300-mΩ

current-limited P-channel MOSFET that can operate

over an input voltage range of 1.62 V to 5.5 V. The

switch is controlled by an on/off input (ON), which can

interface directly with low-voltage control signals. The

TPS22946 includes thermal shutdown protection that

prevents damage to the device when a continuous

over-current condition causes excessive heating by

turning off the switch.

When the switch current reaches the maximum limit,

the TPS22946 operates in a constant-current mode to

prohibit excessive currents from causing damage.

The current limit can be selected using the CL input:

a high CL input sets the current limit to 155 mA, a low

CL input sets the current limit to 70 mA, and a

floating CL input sets the current limit to 30 mA.

If the constant current condition persists after 10 ms,

the switch is turned off and the fault signal pin (OC) is

pulled low. The TPS22946 has an auto-restart feature

which turns the switch on again after 70 ms if the ON

pin is still active. If the TPS22946 remains in an over155

current condition for 5 seconds, the device shuts off

until it is turned on again by setting the ON control

signal off and then on.

If the device is used to protect an LDO, the inrush

current required by the LDO at startup can, in some

cases, exceed the current limit and initiate a blanking

(current limiting) condition. The TPS22946 provides

allowance for this scenario during startup of the LDO by temporarily increasing the current limit to 435 mA

for 8 ms after the load switch is enabled.

The TPS22946 is available in space-saving 6-pin

DSBGA (YZP) package. The device is characterized

for operation over the free-air temperature range of

–40°C to 85°C.