WM8750L Datasheet, PDF (1/56 Pages) Wolfson Microelectronics plc – STEREO CODEC FOR PORTABLE AUDIO APPLICATIONS

WM8750L
Stereo CODEC for Portable Audio Applications
DESCRIPTION
The WM8750L 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, 3-D sound enhancement and automatic
level control for the microphone or line input.
The WM8750L can operate as a master or a slave, with
various master clock frequencies including 12 or 24MHz for
USB devices, or standard 256f_s 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 WM8750L 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 WM8750L is supplied in a very small and thin 5x5mm
QFN package, ideal for use in hand-held and portable
systems.
FEATURES
• DAC SNR 98dB (‘A’ weighted), THD -95B at 48kHz, 3.3V
• ADC SNR 95dB (‘A’ weighted), THD -90dB 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 & 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
• MP3 Player / Recorder
• AAC/WMA/Multi-Format Player / Recorder
• Minidisc Player / Recorder
• Portable Digital Music Systems
BLOCK DIAGRAM
LINPUT1
LINPUT2
LINPUT3
RINPUT3/
HPDETECT
RINPUT2
RINPUT1
MICBIAS
DIFF.
INPUT
L1-R1 OR
L2-R2
M LMIXSEL
U
X
DC MEASUREMENT
M
PGA
U
+ MIC
X
BOOST
LINSEL
ANALOGUE
MONO MIX
RINSEL
M
PGA
U
+ MIC
X
BOOST
DC MEASUREMENT
M
U
X RMIXSEL
50K 50K
Å^DGND
DCVDD
WM8750L
DBVDD
LEFT
LD2LO ^MIXER
LI2LO
ADC
ADC
DIGITAL
FILTERS
VOLUME
DIGITAL
MONO MIX
3D
ENHANCE
DIGITAL
FILTERS
GRAPHIC
EQUALISER
BASS
BOOST
DAC
DAC
RD2LO
MONO
LD2MO ^MIXER
RI2LO
LI2MO
RD2MO
RIGHT
LD2RO ^MIXER
RI2MO
LI2RO
RD2RO
RI2RO
AUDIO
INTERFACE
CLOCK
CIRCUITRY
CONTROL
INTERFACE
HPGND HPVDD
OUT3SW
VREF
ROUT1
M
-1
U
MONOOUT
X
OUT3
LOUT1VOL
LOUT1
MONOVOL
MONOOUT
(phone TX)
ROUT1VOL
ROUT1
LOUT2VOL
-1 ROUT2
INV
ROUT2VOL
LOUT2
ROUT2
L - (-R)
= L+R
WOLFSON MICROELECTRONICS plc
www.wolfsonmicro.com
Product Preview, May 2003, Rev 1.77
Copyright 2003 Wolfson Microelectronics plc