W681308
XXXX PRODUCT DESCRIPTION
21.
Typical Application Reference Circuit
S1
S6
S2
S3
S4
S5
1
2
5
8
0
3
Mode
Up
HangUp
S7
S8
S9
S10
4
6
Down
USB_5V
S11
S12
S17
S13
S18
S23
S14
S19
S24
S15
7
9
Skype
Left
Down1
Dial
+
C1
S16
S20
S25
*
#
Right
Mute
R1
1M
R2
R3
1uF/10V
PUSHBUTTON
PUSHBUTTON
100K
60K
S21
S22
User
Melody
Up1
Q1
1
MMBT3906
DGND
R4
Q2
VDD_3.3V
PZT2222A
300K
Q3
C2
10nF
R5
MMBT3904
100K
C3
R6
2K
DGND
220uF/10V
UARTT
UARTR
AGND
AGND
AGND
C4
R7
DGND
C5 100nF
C6 100nF
UARTT
UARTR
VREF1
33pF
270
1
2
36
35
34
33
32
31
30
29
28
27
26
25
AGND
AGND
UARTT
VREF1
VREF2
MCP
VREF2
MCP
DY1
12M
R8
UARTR
DGND
XTALO
XTALI
VDDL
DVDD
DN
MIC1
1M
3
DGND
1
2
XTALO
XTALI
MCO
4
1
TP1
MCO
C7
RGND
5
W681308_LQFP
DGND
RGND
AGND
SPP
C8
33pF
6
DGND
AGND
SPP
10nF
7
USB_5V
VDD_3.3V
U1
REC1
SPK1
DN
DP
EARP
8
EARP
AVDD
EARN
SPN
C9
100nF
9
VDD_3.3V
DP
USB Connector
EARN
SPN
10
11
12
DGND
DGND
GPIO3
GPIO0
GPIO3
GPIO0
1
VCC
R9
25
DGND
AGND
2
C10
100nF
D-
3
D+
4
R10 25
GND
C11
C12
51pF
C13
C14
C15
R11
D1
VDD_3.3V
VDD_3.3V
DGND
Shielding
DJP1
51pF
30pF
30pF
AGND
10nF
100
R12
LED
D2
VDD_3.3V
DGND
DGND DGND
DGND DGND
C16
The shielding of the
USB connector can't
connect to any GND.
100
LED
100nF
LCD Module (Serial Interface)
AGND
PCM interface is for
External Audio Device or
USB ATA wtih Pro-X
DGND
AGND
VDD_3.3V
C17
100nF
DGND
Figure 16 W681308 Reference Design Application Circuit
21.1
USB VoIP speaker phone application
The application diagram illustrated that the W681308 is a SOC with very low BOM system design. Externally it supports a
variety interfaces such as keypad, LCM, SLIC, SPI flash/EEPROM, Microphone and speakers directly. External 12M Crystal
as well as a 5V to 3.3V linear regulator is required. Ring tone download and playback is through the same Audio DAC path
with a switch for ringing and speech.
61
Rev1.2
NUVOTEM TALEMA [ NUVOTEM TALEMA ]
