AS3515 V14

austriamicrosystems

Product Brief

www.austriamicrosystems.com

Revision 3.04

1

1 General Description

The AS3515 is a low power stereo audio codec and is

designed for Portable Digital Audio Applications. It allows

playback in CD quality and recording in FM-stereo quality. It

has a variety of audio inputs and outputs to directly connect

electret microphones, 16

Ω headset, 4Ω speaker and auxiliary

signal sources via a 10-channel mixer. It only consumes 22mW

in playback mode.

Further the device offers advanced power management

functions. All necessary ICs and peripherals in a flash based

Digital Audio Player are supplied by the AS3515. The power

management block generates 9 different supply voltages out of

the battery supply. CPU, NAND flash, SRAM, memory cards,

LCD back-light, USB RX/TX can be powered. The different

supply voltages are programmable via the serial control

interface. It also contains a charger and is designed for battery

supplies from 1V to 5V.

The AS3515 has an on-chip, phase locked loop (PLL)

controlled, clock generator. It generates 44.1kHz, 48kHz and

other sample rates defined in MP3, AAC, WMA, OGG VORBIS

etc. No additional external crystal or PLL is needed. Further the

AS3515 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) , 48kHz

– ADC: 14bit with 82dB SNR (‘A’ weighted), 16kHz

2 Microphone Inputs

– 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

2 Line Inputs

– volume control via serial interface

– 32 steps @1.5dB and MUTE

– stereo or 2x mono or mono differential

Line Outputs

– volume control via serial interface

– 32 steps @1.5dB and MUTE

– 1Vp @10k

Ω

Audio Mixer

– 10 channel input/output mixer with AGC

– mixes line inputs and microphones with DAC

– left and right channels independent

High Efficiency Headphone Amplifier

– volume control via serial interface

– 32 steps @1.5dB and MUTE

– 2x40mW @16

Ω driver capability

– headphone and over-current detection

– phantom ground eliminates large capacitors

High Power Speaker Amplifier

– volume control via serial interface

– 32 steps @1.5dB and MUTE

– 2x500mW @8

Ω driver capability

– over-current detection

Power Management

– step up for system supply (3.0V – 3.6V)

– charge pump for CPU core (0.85V – 1.8V, 200mA)

– step up for backlight (15V, 38.5mA)

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

– LDO for analogue supply (2.9V, 200mA)

– LDO for peripherals (1.7V-3.3V, 200mA)

– LDO for peripherals (3.1V-3.3V, 200mA)

– LDO for RTC (1.0V-2.5V, 2mA)

– LDO for USB 1.1 transceiver (3.26V, 10mA)

– battery supervision

– 10sec emergency shut-down

Battery Charger

– automatic trickle charge (50mA)

– prog. constant current charging (100-400mA)

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

Real Time Clock

– ultra low power 32kHz oscillator

– 32bit RTC sec counter

– selectable alarm (seconds or minutes)

General Purpose ADC

– 10bit resolution

– 16 inputs analogue multiplexer

Interfaces

– I²S digital audio interface

– 2 wire serial control interface

– watchdog via serial interface

– power good pin

– 128bit unique ID (OTP)

– 17 different interrupts

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

3 Application

Portable Digital Audio Player and Recorder

PDA, Smartphone

Product Brief

AS3515

Stereo Audio Codec with System Power Management