TPS22946

www.ti.com

SLVS984A – SEPTEMBER 2009 – REVISED FEBRUARY 2010

ULTRA-LOW POWER, LOW INPUT VOLTAGE, CURRENT-LIMITED LOAD SWITCH

WITH SHUT-OFF, AUTO-RESTART, AND OVER-CURRENT CONDITION TIME-OUT

Check for Samples: TPS22946

1

FEATURES

DESCRIPTION

•

Ultra-Low Quiescent Current 1 mA (typ)

The TPS22946 is an ultra-low power load switch that

provides

protection

to

systems

and

loads

in

•

Input Voltage Range: 1.62 V to 5.5 V

high-current

conditions.

The

device

contains

a

•

Low ON-Resistance

300-m

Ω 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 is capable of interfacing directly with

–

low-voltage control signals. The TPS22946 includes

–

thermal shutdown protection that prevents damage to

•

Selectable Minimum Current Limit:

the device when a continuous over-current condition

causes excessive heating by turning off the switch.

155 mA, 70 mA, or 30 mA

•

Integrated Inrush Current Timeout (8 ms)

When the switch current reaches the maximum limit,

the TPS22946 operates in a constant-current mode to

•

Shutdown Current: < 1 mA

prohibit excessive currents from causing damage.

•

Thermal Shutdown

The current limit can be selected using the CL input:

•

Fault Blanking

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

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

•

Auto Restart

floating CL input sets the current limit to 30 mA.

•

Over-Current Condition Timeout (Automatic

Disable for Permanent Over-Current)

If the constant current condition still persists after 10

ms, the switch is turned off and the fault signal pin

•

1.8-V Compatible Control Input

(OC)

is

pulled

low.

The

TPS22946

has

an

•

ESD Performance Tested Per JESD 22

auto-restart feature which turns the switch on again

–

6000-V Human-Body Model

after 70 ms if the ON pin is still active. If the

(A114-B, Class II)

TPS22946 remains in an over-current condition for 5

seconds, the device shuts off until it is turned back on

•

Tiny WCSP Package 1.4mm x 0.9 mm (YZP)

by setting the ON control signal off and then on

again.

APPLICATIONS

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

•

Fingerprint Module Protection

current required by the LDO at startup can, in some

•

Portable Consumer Electronics

cases, exceed the current limit and initiate a blanking

•

Mobile Phones

(current

limiting)

condition.

TPS22946

provides

•

Smartphone

allowance for this scenario during startup of the LDO

•

Notebooks

by temporarily increasing the current limit to 435-mA

for 8-ms after the load switch is enabled.

•

GPS Devices

The

TPS22946

is

available

in

space-saving

6-terminal WCSP (YZP) package. It is characterized

for operation over the free-air temperature range of

–40°C to 85°C.

Table 1. FEATURE LIST

INTEGRATED

CURRENT

AUTO-

OVER-

INRUSH

LIMIT

CURRENT LIMIT

RESTART

CURRENT

ENABLE

5.5 V

CURRENT

BLANKING

TIME

TIMEOUT

TIMEOUT

TIME

TPS22946

300 m

Ω

30 mA, 70 mA, or 155 mA

Yes

10 ms

70 ms

6 s

Active high

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas

Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.

Copyright © 2009–2010, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.