WM8350
Production Data
TYPICAL APPLICATIONS
The WM8350 is a complete audio and power management solution for portable media devices. The
device incorporates four programmable step-down switching regulators, two step-up switching
regulators, a full-featured battery charger, four Low Drop-Out (LDO) voltage regulators which can
also serve as hot-swap outputs, a backup supply regulator, two programmable white LED drivers, a
Real-Time Clock (RTC) alongside a 32.768kHz (32kHz) oscillator capable of operating from a backup
battery, a 12-bit auxiliary ADC for precise measurements, a ROM-programmable power management
state machine and numerous protection features all in a single 7x7mm BGA package. When only
battery power is available, a battery switch provides power to all switching regulators (and some
other internal modules). When external power is applied (eg. from USB or Wall adapter), the
WM8350 seamlessly transitions from battery power (a single-cell Lithium battery) to the applicable
external supply. The battery charger is then activated, all internal power for the device is drawn from
the appropriate external power source and the battery is disconnected from the load. Maximum
battery charge current and charge time are programmable. The USB power manager provides
accurate current limiting for the USB pin under all conditions. The hot-swap outputs (LDOs in current-
limited ‘Switch Mode’ operation) are ideal for powering memory cards and other devices that can be
inserted while the system is fully powered.
The integrated Hi-Fi stereo CODEC incorporates preamps and a low-noise bias voltage for
differential microphones, and flexible pseudo-differential drivers for headphone and differential/single-
ended line outputs. External component requirements are reduced as no separate microphone or
headphone amplifiers are required. Digital filter options are available in the ADC and DAC paths, to
cater for application filtering. The WM8350 is capable of operating without any external clock, as it
can derive all required clocks from its internal crystal oscillator, RC clock, and Frequency Locked
Loop. An external low jitter clock may be required in some applications for high performance audio.
PD, February 2011, Rev 4.4
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
