W681310
1. GENERAL DESCRIPTION
The W681310 is a general-purpose single channel PCM CODEC with pin-selectable
μ-Law
or A-Law
companding. The device is compliant with the ITU G.712 specification. It operates from a single +3V
power supply and is available in 20-pin SOG, SSOP and TSSOP package options. Functions
performed include digitization and reconstruction of voice signals, and band limiting and smoothing
filters required for PCM systems. W681310 performance is specified over the industrial temperature
range of –40°C to +85°C.
The W681310 includes an on-chip precision voltage reference and an additional power amplifier,
capable of driving 300Ω loads differentially up to a level of 3.544V peak-to-peak. The analog section is
fully differential, reducing noise and improving the power supply rejection ratio. The data transfer
protocol supports both long-frame and short-frame synchronous communications for PCM
applications, and IDL and GCI communications for ISDN applications. W681310 accepts eight master
clock rates between 256 kHz and 4.800 MHz, and an on-chip pre-scaler automatically determines the
division ratio for the required internal clock.
For fast evaluation and prototyping purposes, the W681310DK development kit is available.
2. FEATURES
•
•
•
•
•
•
•
•
•
•
•
Single +3V power supply (2.7V to 5.25V)
Typical power dissipation of 10 mW,
power-down mode of 0.5
μW
Fully-differential analog circuit design
On-chip precision reference of 0.886 V for
a -5 dBm TLP at 600
Ω
Push-pull power amplifiers with external
gain adjustment with 300
Ω
load capability
Eight master clock rates of 256 kHz to
4.800 MHz
Pin-selectable
μ-Law
and
A-Law
companding (compliant with ITU G.711)
CODEC A/D and D/A filtering compliant
with ITU G.712
Industrial temperature range (–40°C to
+85°C)
Packages: 20-pin SOG (SOP), SSOP and
TSSOP
Pb-Free package options available
•
•
•
•
•
•
•
•
•
•
•
•
ApplIcations
VoIP, Voice over Networks
Digital telephone
systems
and
communication
Wireless voice devices
PABX/SOHO systems
Local loop card
SOHO routers
Fiber-to-curb equipment
Enterprise phones
ISDN equipment
Modems/PC cards
Digital Voice Recorders
-2-
W681310
4. TABLE OF CONTENTS
1. GENERAL DESCRIPTION.................................................................................................................. 2
2. FEATURES ......................................................................................................................................... 2
3. BLOCK DIAGRAM .............................................................................................................................. 3
4. TABLE OF CONTENTS ...................................................................................................................... 4
5. PIN CONFIGURATION ....................................................................................................................... 6
6. PIN DESCRIPTION ............................................................................................................................. 7
7. FUNCTIONAL DESCRIPTION............................................................................................................ 8
7.1. Transmit Path ................................................................................................................................ 8
7.2. Receive Path ................................................................................................................................. 9
7.3. Power Management....................................................................................................................... 9
7.3.1. Analog and Digital Supply ..................................................................................................... 10
7.3.2. Analog Ground Reference Bypass .......................................................................................10
7.3.3. Analog Ground Reference Voltage Outpt .............................................................................10
7.4. PCM INTERFACE ....................................................................................................................... 10
7.4.1. Long Frame Sync.................................................................................................................. 11
7.4.2. Short Frame Sync ................................................................................................................. 11
7.4.3. General Circuit Interface (GCI) ............................................................................................. 11
7.4.4. Interchip Digital Link (IDL)..................................................................................................... 12
7.4.5. System Timing ...................................................................................................................... 12
8. TIMING DIAGRAMS.......................................................................................................................... 13
9. ABSOLUTE MAXIMUM RATINGS.................................................................................................... 20
9.1. Absolute Maximum Ratings ......................................................................................................... 20
9.2. Operating Conditions ................................................................................................................... 20
10. ELECTRICAL CHARACTERISTICS ............................................................................................... 21
10.1. General Parameters .................................................................................................................. 21
10.2. Analog Signal Level and Gain Parameters ...............................................................................22
10.3. Analog Distortion and Noise Parameters ..................................................................................23
10.4. Analog Input and Output Amplifier Parameters.........................................................................24
10.5. DIGITAL I/O ............................................................................................................................... 26
10.5.1.
μ-Law
Encode Decode Characteristics...............................................................................26
10.5.2. A-Law Encode Decode Characteristics ..............................................................................27
10.5.3. PCM Codes for Zero and Full Scale ...................................................................................28
10.5.4. PCM Codes for 0dBm0 Output ...........................................................................................28
11. TYPICAL APPLICATION CIRCUIT ................................................................................................. 29
12. PACKAGE SPECIFICATION .......................................................................................................... 31
-4-
51mcu
京公网安备 11010802033920号
EEWORLD
