W681310SG Nuvoton Technology Corporation of America, W681310SG Datasheet - Page 9

• Manufacturer Part Number: W681310SG
• Description: IC VOICEBAND CODEC 3V 1CH 20SOP
• Manufacturer: Nuvoton Technology Corporation of America
• Type: PCMr

Specifications of W681310SG

• Data Interface: PCM Audio Interface
• Resolution (bits): 8 b
• Number Of Adcs / Dacs: 1 / 1
• Sigma Delta: No
• Voltage - Supply, Analog: 2.7 V ~ 5.25 V
• Voltage - Supply, Digital: 2.7 V ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-SOP
• For Use With: W681360DK - KIT DEVELOPMENT FOR W681360
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7. FUNCTIONAL DESCRIPTION
W681310 is a single-rail, single channel PCM CODEC for voiceband applications. The CODEC
complies with the specifications of the ITU-T G.712 recommendation. The CODEC also includes a
complete -Law and A-Law compander. The -Law and A-Law companders are designed to comply with
the specifications of the ITU-T G.711 recommendation.
The block diagram in section 3 shows the main components of the W681310. The chip consists of a
PCM interface, which can process long and short frame sync formats, as well as GCI and IDL formats.
The pre-scaler of the chip provides the internal clock signals and synchronizes the CODEC sample rate
with the external frame sync frequency. The power conditioning block provides the internal power
supply for the digital and the analog section, while the voltage reference block provides a precision
analog ground voltage for the analog signal processing. The main CODEC block diagram is shown in
section 3.
The A-to-D path of the CODEC contains an analog input amplifier with externally configurable gain
setting (see application examples in section 11). The device has an input operational amplifier whose
output is the input to the encoder section. If the input amplifier is not required for operation it can be
powered down and bypassed. In that case a single ended input signal can be applied to the AO pin or
the AI- pin. The AO pin becomes high input impedance when the input amplifier is powered down. The
input amplifier can be powered down by connecting the AI+ pin to V
an input when AI+ is tied to V
7.1).
7.1. Transmit Path
8
Control
8
8
 /A -
 /A -
Cont
r o
l
 /A -
Cont
r
Control
 /A
-
w
Converter
D/A
A/D
Converter
DD
and the AI- pin is selected as an input when AI+ is tied to V
Receive Path
Figure 7.1 The W681310 Signal Path
f
f
High Pass
C
C
High
Pas
s
= 200Hz
= 200
H
z
Filt
Filter
e
Transmit Path
Ant -
Ant
i
- 9 -
f
f
Smoothing
C
Smoot
hi n
g
C
= 3400Hz
H
z
=
3400
H
z
= 3400Hz
Filter
Filter
Filter
1
Filter
Filter
Filter
- Alias
Aliasing
i n
g
Ant - Alias
Ant - Aliasing
Smoot
Smoothing
hi n
g
Filter
Filter
Filter
2
i Filter
Filter
-
Publication Release Date: January 2011
DD
or V
SS
VA
V
G
. The AO pin is selected as
AG
+
-
+
+ -
- +
+
-
W681310
SS
PAO+
PAO
RO -
AI+
PAI
AI -
AO
Revision B17
(see Table
-