Product Brief
January 2002
HF1627-RD
Hands-Free DSP1627 Reference Design
Features
Software
Full-duplex speakerphone operation including state-
of-the-art code implementing:
s
Adaptive acoustic echo canceling (AEC)
s
Noise suppression (NS)
s
Line echo canceling (LEC)
s
Tunable parameters
s
Voice memo recorder (VMR) option
Hardware
s
Agere Systems Inc.'s DSP1627 flash 100 MIPS
DSP (supports pin-compatible DSP1629)
s
Optional daughter card memory module:
-- 512K x 16, 10 ns SRAM (ERAMLO)
-- 128K x 16, 6 ns SRAM (ERAMHI)
s
Agere CSP1027 full-duplex codecs
s
Audio interface supports any cellular phone with
analog interface (i.e., AMPS, TDMA, GSM,
CDMA)
s
PC-compatible serial interface
s
Supports DSP1627 software development tools
(HDS JTAG interface)
s
Internal jumpers for custom configuration
s
Adjustable gain for telephone interface
s
8 V microphone phantom power on input
s
Output is line-level (1.0 Vrms) into 600
, ac cou-
pled
Description
The HF1627-RD is a reference design and demon-
stration platform consisting of an Agere DSP1627
executing a high-quality automotive hands-free
speakerphone application. The system functionality
is controlled by DSP software, which is contained in
Flash ROM. This platform is enclosed in a small 5 x
3 x 1 in. case and is powered by 12 Vdc, making it
suitable for automobile in-cabin demonstrations. This
is important because, since real life conditions vary
widely, this system allows for accurate field testing
and parameter tuning. Complete schematics and
documentation are provided for fast design turn-
around.
Standard audio jacks provide analog audio connec-
tions to the telephone, microphone, and stereo sys-
tem inside the automobile.
The codec sample rate is set at 8 kHz (default).
Other sample rates (up to 24 kHz) can be supported.
The serial port is used to connect to a standard PC
for viewing and setting tunable parameters though a
supplied software utility program. Thus, the speaker-
phone performance can be tailored for personal pref-
erences and a wide variety of vehicle interiors.
The Agere DSP1627 provides the signal processing
required to implement the full-duplex speakerphone.
This includes acoustic echo canceling (AEC), noise
suppression (NS), and line echo canceling (LEC).
Other available software modules such as a voice
memo recorder (VMR) functions can run simulta-
neously on this platform.
The AEC continuously adapts to the ever-changing
acoustical environment in the automotive cabin. This
is required, for example, when a passenger opens a
window or the driver adjusts the sun visor. Agere's
AEC algorithms provide state-of-the-art echo cancel-
lation. The AEC provides up to 50 dB of echo sup-
pression. The NS algorithm has been optimized to
provide 10 dB of noise suppression with negligible
speech distortion.
Product Brief
January 2002
HF1627-RD
Hands-Free DSP1627 Reference Design
Agere Systems Inc. reserves the right to make changes to the product(s) or information contained herein without notice. No liability is assumed as a result of their use or application.
Copyright 2002 Agere Systems Inc.
All Rights Reserved
January 2002
PB02-035AUTO (Replaces PN00-015AUTO)
For additional information, contact your Agere Systems Account Manager or the following:
INTERNET:
http://www.agere.com
E-MAIL:
docmaster@agere.com
N. AMERICA:
Agere Systems Inc., 555 Union Boulevard, Room 30L-15P-BA, Allentown, PA 18109-3286
1-800-372-2447, FAX 610-712-4106 (In CANADA: 1-800-553-2448, FAX 610-712-4106)
ASIA:
Agere Systems Hong Kong Ltd., Suites 3201 & 3210-12, 32/F, Tower 2, The Gateway, Harbour City, Kowloon
Tel. (852) 3129-2000, FAX (852) 3129-2020
CHINA: (86) 21-5047-1212 (Shanghai), (86) 10-6522-5566 (Beijing), (86) 755-695-7224 (Shenzhen)
JAPAN: (81) 3-5421-1600 (Tokyo), KOREA: (82) 2-767-1850 (Seoul), SINGAPORE: (65) 778-8833, TAIWAN: (886) 2-2725-5858 (Taipei)
EUROPE:
Tel. (44) 7000 624624, FAX (44) 1344 488 045
Description
(continued)
Figure 1. Hands-Free DSP1627 Reference Design Block Diagram
5-7554 (F)
BUFFER/GAIN
(NON)
BUFFER/GAIN
(INV)
VARIABLE GAIN
(NON)
VARIABLE GAIN
(INV)
POT
CSP1027 CODEC
VREG
SMODE[0:2]
CLK
RST
AOUTP
CKI2
RST
TRST
ERAMLO
DATA[0:15]
ADD[0:15]
ERAMHI
RWN
IOBIT[0:4]
ION
IOBIT5
DSP1627
CKI
OBE2
IBF2
INT0
EXM
OBE1
IBF1
SIO2
CKO
IOBIT6
SIO1
LATCH/SWITCHES
CS
R/
W
16
EN
512K x 16
RAM
VMR OPTION
32K--16K PAGES
4100--7FFF
R/
W
CS
16
14
5
128K x 16
EEPROM
VMR OPTION
8K--16K PAGES
C000--FFFF
R/
W
CS
16
14
3
UART
R/W
CS
8
4
RS
T
IN
T
XIN
CSP1027 CODEC
SMODE[0:2]
CLK
RST
POT
TDM BUS
SWSAMP[0:2]
(JUMPERS)
SWGEN[0:3]
(JUMPERS)
SWBAUD[0:1]
(JUMPERS)
ERAMLO MAPPED
ERAMHI MAPPED
BATTERY BACKUP
RS232
LEVEL
CONVERTER
DSP-CKO
VCC5D
OPTIONAL
OPTIONAL
TEST HEADER
HEADER/CONNECTOR
TCS INTERFACE
TEST HEADER
VCC5D
12 MHz OR 24 MHz
OSCILLATOR
VCC5D
MASTER
RESET
POWER-ON RESET
VOLTAGE
REGULATORS
VCC5D
VCC5A
VCC8A
ON/OFF
12 Vdc
TDM BUS
TEST
VCC5D
TDM MODE 2
VCC5A
TDM MODE 2
MIC
MIC
AOUTP
12 MHz OR 24 MHz
TP
VCC5A
VCC5A
VCC8A
ANALOG
DIGITAL
SERIAL I/O
HEADER/
CONNECTOR
HEADER
MICROPHONE
EARPHONE
FAR OUT
FAR IN
NEAR OUT
NEAR IN
2.5 mm MONO
3.5 mm STEREO
IN-CABIN
DIGITAL PHONE INTERFACE
ANALOG PHONE INTERFACE
(2.5 mm STEREO)
PC
SERIAL
PORT
3
2
4
712-1212
1 2 3
4 5 6
7 8 9
* 0 #