WM8971L Datasheet, PDF (1/56 Pages) Wolfson Microelectronics plc – STEREO CODEC FOR PORTABLE AUDIO APPLLICATIONS

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WM8971L
Stereo CODEC for Portable Audio Applications
DESCRIPTION
The WM8971L is a low power, high quality stereo codec
designed for portable digital audio applications.
The device integrates complete interfaces to stereo or mono
microphones and a stereo headphone. External component
requirements are drastically reduced as no separate
microphone or headphone amplifiers are required.
Advanced on-chip digital signal processing performs
graphic equaliser, and automatic level control for the
microphone or line input.
The WM8971L can operate as a master or a slave, with
various master clock frequencies including 12 or 24MHz for
USB devices, or standard 256fs rates like 12.288MHz and
24.576MHz. Different audio sample rates such as 96kHz,
48kHz, 44.1kHz are generated directly from the master
clock without the need for an external PLL.
The WM8971L operates at supply voltages down to 1.8V,
although the digital core can operate at voltages down to
1.42V to save power, and the maximum for all supplies is
3.6 Volts. Different sections of the chip can also be powered
down under software control.
The WM8971L is supplied in a very small and thin 5x5mm
QFN package, ideal for use in hand-held and portable
systems.
BLOCK DIAGRAM
FEATURES
• DAC SNR 98dB (‘A’ weighted), THD –84dB at 48kHz, 3.3V
• ADC SNR 95dB (‘A’ weighted), THD -82dB at 48kHz, 3.3V
• Complete Stereo / Mono Microphone Interface
- Programmable ALC / Noise Gate
• On-chip 400mW BTL Speaker Driver (mono)
• On-chip Headphone Driver
- >40mW output power on 16Ω / 3.3V
- THD –80dB at 20mW, SNR 90dB with 16Ω load
- No DC blocking capacitors required (capless mode)
• Separately mixed mono output
• Digital Graphic Equaliser
• Low Power
- 7mW stereo playback (1.8V / 1.5V supplies)
- 14mW record and playback (1.8V / 1.5V supplies)
• Low Supply Voltages
- Analogue 1.8V to 3.6V
- Digital core: 1.42V to 3.6V
- Digital I/O: 1.8V to 3.6V
• 256fs / 384fs or USB master clock rates: 12MHz, 24MHz
• Audio sample rates: 8, 11.025, 16, 22.05, 24, 32, 44.1, 48,
88.2, 96kHz generated internally from master clock
• 5x5x0.9mm QFN package
APPLICATIONS
• Digital Still Cameras
• MP3 Player / Recorders
• Minidisc Player / Recorders
• Portable Digital Music Systems
WOLFSON MICROELECTRONICS plc
www.wolfsonmicro.com
Advanced Information, March 2004, Rev 3.0
Copyright 2004 Wolfson Microelectronics plc