AS3518 V10

austriamicrosystems

Preliminary Product Brief, Confidential

© 2003-2006, austriamicrosystems AG, 8141 Unterpremstaetten, Austria-Europe. All Rights Reserved.

www.austriamicrosystems.com

Revision 0.5

1

1 General Description

The AS3518 is a low power stereo audio codec and is

designed for Portable Digital Audio Applications. It allows

playback and recording in CD quality. It has a variety of audio

inputs and outputs to directly connect electret microphones,

16

Ω/32Ω headsets and auxiliary signal sources via a 10-

channel mixer. It consumes less than 20mW in playback mode.

Further the device offers advanced power management

functions. All necessary ICs and peripherals in a Digital Audio

Player are supplied by the AS3518. The different regulated

supply voltages are programmable via the serial control

interface. AS3518 also contains a Li-Io battery charger. The

single supply voltage may vary from 1.0V to 5.5V.

The AS3518 has an on-chip, phase locked loop (PLL) which

generates the needed internal CODEC master clock. I2S

Frame and shift-clock has to be applied from the processor for

playback and recording. Further the AS3518 has an

independent 32kHz real time clock (RTC) on chip which allows

a complete power down of the system CPU.

2 Key Features

• Multi-bit Sigma Delta Converters

– DAC: 18bit with 94dB SNR (‘A’ weighted)

– ADC: 20bit with 90dB SNR (‘A’ weighted)

– Sampling Frequency: 8-48kHz

• 1 Microphone Input

– 3 gain pre-setting (28dB/34dB/40dB) and AGC

– 32 gain steps @1.5dB and MUTE

– supply for electret microphone

– microphone detection

– remote control by switch

• 3 Line Inputs

– volume control via serial interface

– 32 steps @1.5dB and MUTE

– stereo or 2x mono or mono differential

• Audio Mixer

– 8 channel input/output mixer with AGC

– mixes line inputs and microphones with DAC

– left and right channels independent

• Line Output

– volume control via serial interface

– 32 steps @1.5dB and MUTE

– 1Vp @10k

Ω

– Stereo 2*5mW @16

Ω

– Mono differential 10mW @32

Ω (earpiece)

• High Efficiency Headphone Amplifier

– volume control via serial interface

– 32 steps @1.5dB and MUTE

– 2x60mW @16

Ω driver capability

– headphone and over-current detection

– phantom ground eliminates large capacitors

• Power Management

– step down for CPU core (0.65V-3.4V, 250mA)

– step down for peripheral (0.65V-3.4V, 250mA)

–step up for backlight (15V (25V), 38mA),

dimming, voltage control mode

– LDO for AFE analog supply (2.9V, 200mA)

– LDO for AFE digital supply (2.9V, 200mA)

– LDO for peripherals (1.2V-3.5V, 200mA)

– LDO for peripherals e.g. USB (1.2V-3.5V, 200mA)

– power supply supervision

– hibernation modes

– 5sec and 10sec emergency shut-down

• Battery Charger

– automatic trickle charge (50mA)

– prog. constant current charging (50-460mA)

– prog. constant voltage charging (3.9V-4.25V)

– current limitation for USB mode

• Real Time Clock

– ultra low power 32kHz oscillator

– 32bit RTC sec counter, 96 days auto wake-up

– selectable alarm (seconds or minutes)

– 128bit free SRAM for random settings

– 32kHz clock output to peripheral

– voltage generation

– <1uA total power consumption

• General Purpose ADC

– 10bit resolution

– 21 inputs analog multiplexer

• Interfaces

– I²S digital audio interface and SPDIF

– 2 wire serial control interface

– reset pin, watchdog, power good pin

– PWM output

– 64bit unique ID (OTP)

– 23 different interrupts

• Package CTBGA64 [7.0x7.0x1.1mm] 0.8mm pitch

3 Application

Portable Digital Audio Player and Recorder

PDA, Smartphone

Preliminary Product Brief, Confidential

AS3518

Stereo Audio Codec with enhanced System Power Management