STPMIC1 datasheet(29/140 Pages) STMICROELECTRONICS

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LDOs contain the following functions:

Soft-start circuit is implemented to limit input inrush current when LDO starts. LDO soft-start duration is

defined by tSSLDO parameter. For more details, Figure 38. LDO start-up/shutdown timings

Overcurrent limit circuit - When the load on the output of the LDO exceeds overcurrent limit threshold

ILDOLIM, LDO starts decreasing the output voltage limiting the output current. When the overcurrent condition

on LDO lasts for more than tOCPDB_LDO, LDOx_OCP interrupt is generated. For a detailed behavior of the

device on OCP event refer to Section 5.4.7 Overcurrent protection (OCP)

Output discharge circuit (passive), to discharge LDO output decoupling capacitor energy. In power down

sequence, it allows LDO voltage to be down before disabling next regulators in next ranking slot.

Output discharge is by default active when LDO is disabled.

Different behavior can be programmed in Table 28. LDO14_PD_CR and Table 29. LDO56_VREF_PD_CR

registers.

Note:

To ensure the LDO functionality, BUCK2IN input must be always connected to VIN power supply.

Figure 38. LDO start-up/shutdown timings

4.2.2

LDO regulators - special features

LDO3

STPMIC1

LDO regulators

DS12792 - Rev 7

page 29/140

STPMIC1 数据表(PDF) 29 Page - STMicroelectronics