WM8310: Integrated Power Management Subsystem

Description

WM8310 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. WM8310 is specifically designed to operate as a system PMIC supporting a variety of industry standard processors and accessories in a wide range of 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.

The WM8310 power management subsystem comprises of four programmable DC-DC converters, 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.

WM8310 can be powered from a battery, a wall adaptor or from a USB power source. 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 WM8310.

A linear on-chip battery charger supports trickle charging and constant current / constant voltage charging of single-cell lithium-ion / lithium-polymer batteries. The charge current, termination voltage, and charger time-out are programmable. WM8310 detects and handles battery fault conditions with a minimum of system software involvement.

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.

WM8310 includes a crystal oscillator, an internal RC oscillator and Frequency Locked Loop (FLL) 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 WM8310 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 WM8310 is supplied in a 7x7mm 169-ball BGA package, ideal for use in portable systems. The WM8310 forms part of the Wolfson series of audio and power management solutions.