NPM1100-CAAA-R datasheet(15/58 Pages) NORDIC

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6 Core components

6.1 SYSREG — System regulator

The input voltage to the system voltage regulator (SYSREG) is supplied by

VBUS. VBUS voltage is supplied

by AC wall adapters or USB ports.

SYSREG is a linear voltage regulator (LDO) that supplies VINT when the device is in normal state.

Features of SYSREG are the following:

• 5 V linear voltage regulator (LDO) supplying VINT when

VBUS is connected

• Operating voltage up to 6.7 V

• Overvoltage protection to 20 V

• USB port detection and control pin for setting the current limit on

VBUS

Note: The

VSYS and DEC pins must not be externally supplied.

6.1.1 USB port detection and VBUS current limiting

The device supports automatic detection of USB port type in line with the Battery Charging Specification

v1.2 found on usb.org.

Primary detection is performed for Standard Downstream Port (SDP), Dedicated Charging Port (DCP), and

Charging Downstream Port (CDP) USB ports. The detection sequence starts once

VBUS is connected and

completes after TCONN0 .

If SDP is detected, the

VBUS current limit is set to 100 mA. An external microcontroller with a USB

interface can negotiate a 500 mA limit with the USB host. It then raises the

VBUS current limit using a

GPIO to control

ISET. This is referred to as USB port negotiation.

If DCP/CDP is detected, the

VBUS current limit is set to 500 mA. In this case, ISET configuration is

ignored.

It is possible to configure the device to set the

VBUS current limit to either 100 mA or 500 mA using ISET

and disabling USB port detection.

The following table describes

ISET, D+, and D- configurations to fix VBUS current limit or set VBUS

current limit based on either USB port detection or USB port negotiation.

4445_367 v1.0

NPM1100-CAAA-R Datasheet(PDF) 15 Page - Nordic Semiconductor