The linear voltage regulator/load switch (LDOSW) can be used as a switch or LDO regulator both in Active and Hibernate modes.

LDOSW is supplied from BOOST output (VINT). LDO or load switch must be selected prior to enabling LDOSW in register LDOSW.SEL. The mode can also be controlled through a GPIO by selecting PINCTRL in register LDOSW.SEL and configuring register LDOSW.GPIO.

The power modes for LDOSW are configured in register LDOSW.SEL and consist of the following:
  • Auto – This is the default mode where the device operating mode determines the LDOSW mode. When the device is in Active mode, LDOSW is in High Power mode. When the device is in Hibernate mode, LDOSW is in Ultra-Low Power mode.
  • High Power – Output current up to 50 mA.
  • Ultra-Low Power – Output current up to 2 mA.

Overcurrent protection is enabled by default. It can be disabled in register CONF. The current limits for soft start and overcurrent protection can be configured in register PRGOCP. The LSOUT/VOUTLDO pin is actively discharged when LDOSW is disabled.

Note: GPIO controls must be disabled before entering Hibernate or Hibernate_PT mode.

LDO mode

The LDO is OFF by default. LDO mode is set by selecting LDO in register LDOSW.SEL. The output voltage is configurable in 50 mV steps in register LDOSW.VOUT and enabled in register LDOSW.LDOSW.

Load switch

The load switch is OFF by default. Load switch mode is set by selecting LoadSW in register LDOSW.SEL and enabled in register LDOSW.LDOSW.