L9001 datasheet(14/38 Pages) STMICROELECTRONICS

14 / 38 page

Power supply

L9001

14/38

DS12089 Rev 2

Power supply

5.1

Configuration

The device regulators must be configured by proper connection of CONFx input pins.

VDD1 regulator output voltage level must be configured through pin CONF3.

The pin has a tri-state configuration: LOW, MID and HIGH. The output of the regulator

corresponding to each configuration is summarized in the table below:

VDD2 regulator mode must be configured in either Buck regulator or LDO through pin CONF2.

ADCLDO output voltage must be configured by proper configuration on pin CONF1.

CONF1 and CONF2 pin have a LOW/HIGH configuration. The regulator configurations

corresponding to each option are summarized in the table below.

In order to have the described configuration, pin CONFx must be connected as follows:



LOW configuration: pin CONFx must be connected to ground;



HIGH configuration: pin CONFx must be connected to VS supply;



MID configuration (only for CONF3): pin CONF3 must be left open.

Voltage levels at CONF1, CONF2 and CONF3 pins are latched at power-up; in addition,

CONF1 and CONF2 have an open load check. In case of disconnected pins all output

voltages are disabled, the device stays in OFF state and a new power-up sequence would

be needed to refresh the signal values on the input pins.

5.2

VDD1 regulator

VDD1 is an asynchronous switch mode power supply with integrated FET. The input voltage

of VDD1 regulator is VS pin; the output voltage generated by the buck can be configured as

3.3 V / 5 V / 6 V as described in Section 5.1.

The output voltage can be directly used by external loads and must be connected also to pin

VR1. In fact VR1 is the output of a LDO bypass regulator which is used to keep regulation

active when the output current demand goes below a specified threshold ILIM_BP1. In this

bypass mode, the output voltage is regulated according to the VR1_byp parameter. Such

mode is used for example when the system needs to reduce the overall consumption by

entering the Low Power mode (see dedicated Section 8.2.4 for details)

Table 7. CONF3 configuration

Low config

MID config

HIgh config

CONF3

VDD1 = 3.3 V

VDD1 = 5 V

VDD1 = 6 V

Table 8. CONF2 and CONF1 configuration

Low config

High config

CONF1

VADC = 3.3 V

VADC = 5 V

CONF2

VDD2 as Buck

VDD2 as Linear

L9001 Datasheet(PDF) 14 Page - STMicroelectronics

L9001 Datasheet(HTML) 14 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38

Datasheet Download

Link URL