Wolfson WM8320处理器电源管理方案

首页 » 解决方案 » Wolfson WM8320处理器电源管理方案

Wolfson WM8320处理器电源管理方案

作者：时间：2009-10-15 11:12 来源：

Wolfson 公司的WM8320是综合的处理器电源管理子系统,提供高性价比的灵活的单片解决方案,特别适合于低功率手提应用. WM8320支持ARM9, ARM11和ARM Cortex-A系列处理器,具有电源管理,系统控制以及其它用于多功能模拟测量的ADC,128位伪随机ID,带叫醒的安全RTC和系统LED输出指示电源状态和故障状态等功能,主要用在手机,智能手机,电子书,PMP,移动互联网设备(MID),电子游戏,上网本和机顶盒.本文介绍了WM8320的主要特性,方框图以及在手提媒体播放器(PMP), 手提导航设备, 数码相机, 数码相框, VOIP电话, 电子阅读器和婴儿监视器的应用框图以及WM8320评估板详细电路图.

Processor Power Management Subsystem

WM8320 is an integrated power-management subsystem which provides a cost-effective, flexible, single-chip solution for power management, specifically targeted at the requirements of a range of low-power portable applications.

WM8320 is specifically designed to operate as a system PMIC supporting the ARM9™, ARM11™ and ARM Cortex-A™ series processors at the heart of a range of low-power
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 contents. An external EEPROM can be used to configure the WM8320 for development purposes.

The WM8320 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 WM8320.

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.

WM8320 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 (SRTC) 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 WM8320 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 <10uA, making it particularly suitable for portable applications.

The WM8320 is supplied in a 7x7mm 169-ball BGA package, ideal for use in portable systems. The WM8320 forms part of the Wolfson series of audio and power management solutions, and is widely register compatible with the WM831X family of PMIC devices.

WM8320主要特性:

Power Management

2 x DC-DC buck converter (0.6V - 1.8V, up to 1.2A, DVS)

2 x DC-DC buck converter (0.85V - 3.4V, up to 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 10mA)

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

7x7mm, 169-ball BGA package, 0.5mm ball pitch

WM8320应用:

Cellular Handsets

Smartphones

Electronic Books

Portable Media Players

Mobile Internet Devices

Electronic Gaming Devices

Netbooks

Set Top Box