TPS2020, TPS2021, TPS2022, TPS2023, TPS2024

POWER-DISTRIBUTION SWITCHES

SLVS175A – DECEMBER 1998 – REVISED NOVEMBER 1999

20

POST OFFICE BOX 655303

APPLICATION INFORMATION

generic hot-plug applications (see Figure 40)

In many applications it may be necessary to remove modules or pc boards while the main unit is still operating.

These are considered hot-plug applications. Such implementations require the control of current surges seen

by the main power supply and the card being inserted. The most effective way to control these surges is to limit

and slowly ramp the current and voltage being applied to the card, similar to the way in which a power supply

normally turns on. Because of the controlled rise times and fall times of the TPS202x series, these devices can

be used to provide a softer start-up to devices being hot-plugged into a powered system. The UVLO feature

of the TPS202x also ensures the switch will be off after the card has been removed, and the switch will be off

during the next insertion. The UVLO feature guarantees a soft start with a controlled rise time for every insertion

of the card or module.

Power

Supply

Block of

Circuitry

TPS2024

GND

IN

IN

EN

OUT

OUT

OUT

OC

0.1

µF

1000

µF

Optimum

2.7 V to 5.5 V

PC Board

Overcurrent Response

Figure 40. Typical Hot-Plug Implementation

first after insertion. The typical rise time of the switch is approximately 9 ms, providing a slow voltage ramp at

the output of the device. This implementation controls system surge currents and provides a hot-plugging

mechanism for any device.