L6460 datasheet(89/139 Pages) STMICROELECTRONICS

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L6460

Low voltage power switches

Doc ID 17713 Rev 1

89/139

Low voltage power switches

Low voltage power switches are analog switches designed to operate from a single +2.4 V

to +3.6 V VGPIO_SPI supply. They are intended to provide and remove power supply to low

voltage devices. When switched on, they connect the VGPIO_SPI pin to their output pin

(GPIO[6] for low voltage power switch 1 or GPIO[7] for low voltage power switch 2) thus

powering the device connected to it. The turning on and off of each switch can be controlled

through serial interface.

L6460 provides 2 low voltage power switches, each of them has current limitation to

minimum 150mA to limit inrush current when charging a capacitive load. When the limit

current has been reached, for more than a Tfilter time, then a flag is activated; this flag is

latched in the central logic and can be cleared by the firmware. Please note that, in case of

capacitive load, the current limit is reached the first time the low power switch is turned on:

therefore the user will find a limit flag that must be cleared.

The 2 low voltage power switches can be externally paralleled to obtain a single super low

voltage power switch. Low voltage pass switches sink current needed for their functionality

from pin VGPIO_SPI, they never inject current on this pin.

Figure 27.

Low power switch block diagram

EnLowVSw[x]

GPIO[6] (LPS 1)

GPIO[7] (LPS 2)

Current

Limit

Sensor

VGPIO_SPI

LowVSwIlim[x]

To SPI

LowVSwIlimLth[x]

ClrLowVrSwLth

Reset State

GPIO[6]/GPIO[7]

Driver

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