Production Data
WM8321
TYPICAL APPLICATIONS
The WM8321 is designed as a system PMIC device that generates configurable DC supplies to
power processors and associated peripherals within a system. The WM8321 provides four DC-DC
synchronous buck (step-down) converters. Two of these can operate in dual mode, providing an
increased current capability. Eleven 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 BuckWiseTM 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 / cellular handset applications.
The WM8321 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 WM8321 supports the programming and verification of the integrated
OTP memory.
A backup battery supply can be connected to the WM8321 in order to maintain the Real Time Clock
(RTC) in the absence of the primary supply.
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 WM8321
also provides two LED drivers, which can be controlled manually or configured as status indicators for
the OTP memory programmer or operating power state.
PD, February 2012, Rev 4.0
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
