WM8325 Datasheet, PDF (1/254 Pages) Wolfson Microelectronics plc – Processor Power Management Subsystem

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WM8325
Processor Power Management Subsystem
DESCRIPTION
The WM8325 is an integrated power-management subsystem
which provides a cost-effective, flexible, single-chip solution for
power management. It is specifically targeted at the
requirements of a range of low-power portable consumer
products, but is suitable to any application with a multimedia
processor. The WM8325 is designed to operate as a system
PMIC supporting the ARM9™, ARM11™ and ARM Cortex-A™
processors, but is also capable of supporting the majority of
application and mobile processors at the heart of a wide range
of low-power consumer multimedia applications.
The start-up behaviour and configuration is fully programmable
in an integrated OTP non-volatile memory. This highly flexible
solution helps reduce time-to-market, as changing application
requirements can be very easily accommodated in the OTP.
The InstantConfig^TM interface enables an external EEPROM to
configure the WM8325.
The WM8325 power management subsystem comprises four
programmable DC-DC converters and eleven LDO regulators
(four of which are low-noise for supplying sensitive analogue
subsystems). The integrated OTP bootstrap circuitry controls
the start-up sequencing and voltages of the converters and
regulators as well as the sequencing of system clocks.
The DC-DC converters deliver high performance and high
efficiency across a wide range of operating conditions. They
are optimised to support the high load current transients seen
in modern processor core domains. DC-DC3 / DC-DC4 can be
connected together and operated in ‘dual’ mode to support an
increased current load of up to 1.6A
An on-chip regulator provides power for always-on PMIC
functions such as register map and the RTC. The device
provides autonomous backup battery switchover. A low-power
LDO is included to support ‘Alive’ processor power domains
external to the WM8325.
A 12-bit Auxiliary ADC supports a wide range of applications
for internal as well as external analogue sampling, such as
voltage detection and temperature measurement.
WM8325 includes a crystal oscillator and an internal RC
oscillator to generate all clock signals for autonomous system
start-up and processor clocking. A Secure Real-time Clock (S-
RTC) and alarm function is included, capable of waking up the
system from low-power modes. A watchdog function is
provided to ensure system integrity.
To maximise battery life, highly-granular power management
enables each function in the WM8325 subsystem to be
independently powered down through a control interface or
alternatively through register and OTP-configurable GPIOs.
The device offers a standby power consumption of <7uA,
making it particularly suitable for portable applications.
The WM8325 is supplied in an 8x8mm 81-lead QFN package,
ideal for use in portable systems. The WM8325 forms part of
the Wolfson series of audio and power management solutions,
and is widely register compatible with the WM831X devices.
FEATURES
Power Management
 1 x DC-DC synchronous buck converter
(0.6V - 1.8V, 2.5A, DVS)
 1 x DC-DC synchronous buck converter
(0.6V - 1.8V, 1.25A, DVS)
 2 x DC-DC synchronous buck converters
(0.85V - 3.4V, 1A)
 1 x LDO regulator (0.9V - 3.3V, 300mA, 1)
 2 x LDO regulators (0.9V - 3.3V, 200mA, 1)
 3 x LDO regulators (0.9V - 3.3V, 100mA, 2)
 2 x Low-noise LDO regulators (1.0V - 3.5V, 200mA, 1)
 2 x Low-noise LDO regulators (1.0V - 3.5V, 150mA, 2)
 1 x ‘Alive’ regulator (0.8V – 1.55V, up to 25mA)
System Control
 I²C or SPI compatible primary control interface
 Comprehensive interrupt scheme
 Watchdog timer and system reset control
 Autonomous power sequencing and fault detection
 OTP memory bootstrap configuration function
Additional Features
 Auxiliary ADC for multi-function analogue measurement
 128-bit pseudo-random unique ID
 Secure Real-Time Clock with wake-up alarm
 12 x configurable multi-function (GPIO) pins
 Comprehensive clocking scheme: low-power 32kHz RTC
crystal oscillator, GPIO clock output and 4MHz RC clock
for power management
 System LED outputs indicating device power state, and
fault status
Package Options
 8 x 8 x 0.85mm, 81-lead QFN package
APPLICATIONS
 Cellular Handsets
 Smartphones
 Electronic Books
 Portable Media Players
 Mobile Internet Devices
 Electronic Gaming Devices
 Netbooks
 Smartbooks
 Set Top Box
 Digital Picture Frames
WOLFSON MICROELECTRONICS plc
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Production Data, February 2012, Rev 4.0
Copyright 2012 Wolfson Microelectronics plc