Pre-Production
WM8311
TYPICAL APPLICATIONS
The WM8311 is designed as a system PMIC device that manages multiple power supply paths (wall
adapter, USB, battery) and generates configurable DC supplies to power processors and associated
peripherals within a system. The WM8311 provides three DC-DC synchronous buck (step-down)
converters and one DC-DC boost (step-up) converter. Seven LDO regulators provide a high degree of
flexibility to provide power to multiple devices, with the capability to power-up and power-down
different circuits independently.
Two of the DC-DC buck converters incorporate Wolfson’s BuckWise™ technology specifically
designed to handle rapid changes in load current; programmable slew rate DVS is also provided, as
required by modern application processors. Selectable operating modes on all of the DC-DC
converters allow each converter to be optimally configured for light, heavy or transient load
conditions. Flexible operating configurations allow the converters to be tailored for minimum PCB
area, maximum performance, or for maximum efficiency. The analogue LDOs provide low-noise
outputs suitable for powering sensitive circuits such as RF / Wi-Fi / bluetooth radio applications.
The WM8311 powers up the converters and LDOs according to a programmable sequence. A
configurable ‘SLEEP’ state is also available, providing support for an alternate configuration, typically
for low-power / standby operation. The power control sequences and many other parameters can be
stored in an integrated user-configurable OTP (One-Time Programmable) memory or may be loaded
from an external memory. The WM8311 supports the programming and verification of the integrated
OTP memory.
The WM8311 provides power path management which seamlessly switches between wall adapter,
USB and battery power sources according to the prevailing conditions. A backup power source is also
supported in order to maintain the Real Time Clock (RTC) in the absence of any other supplies. The
WM8311 provides a configurable battery charger for the main battery, powered from either the wall
adapter or USB supplies. The backup power source is maintained using a constant-voltage output
from the WM8311.
Programmable GPIO pins may be configured as hardware inputs for general use or for selecting
different power management configurations. As outputs, the GPIOs can provide indications of the
device status, or may be used as control signals for other power management circuits. The WM8311
also provides two LED drivers, which can be controlled manually or configured as status indicators for
the OTP memory programmer, operating power state or battery charger.
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PP, May 2012, Rev 3.1
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
