Texas Instruments DEM-PCM2912 EVM, Руководство пользователя, Страница: 11 / 43

www.ti.com
1.2 Pin Assignments and Terminal Functions
PCM2912PJT
(32-pin TQFP)
1
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
32
10
31
11
30
12
29
13
28
14
27
15
26
16
25
PGND
V
IN
V
CCP
V
CCA
TEST1
NC
TEST0
AGND
SSPND
V
COM2
MMUTE
V
COM1
REC
FR
PLAY
FL
BGND
V
BU
S
D
-
D+
V
D
D
DGND
XTO
XTI
POWER MAMP V
R
O
U
T
V
C
C
R
HGND V
C
C
L
V
L
O
U
T
MBIAS
PCM2912PJT
(Top View)
Pin Assignments and Terminal Functions
Figure 1-1 shows the pin assignments for the PCM2912. Table 1-1 lists the terminal functions.
Figure 1-1. PCM2912 Pin Assignments
Table 1-1. PCM2912 Terminal Functions
TQFP-36
Name Terminal I/O Description
BGND 1 – Reference for internal regulator
V
BUS
2 – Connect to USB power (V
BUS
)
D– 3 I/O USB differential input/output minus
D+ 4 I/O USB differential input/output plus
V
DD
5 – Digital power supply
DGND 6 Digital ground
XTO 7 O Crystal oscillator output
XTI 8 I Crystal oscillator input
FL 9 – External filter pin of left channel (optional)
FR 10 – External filter pin of right channel (optional)
V
COM1
11 – Common voltage for ADC, DAC and analog front-end (V
CCA
/2). Decoupling capacitor should
be connected to AGND.
V
COM2
12 – Common voltage for headphone (V
CCA
/2). Decoupling capacitor should be connected to
AGND.
AGND 13 – Analog ground
NC 14 – Not connected
V
CCA
15 – Analog power supply
V
IN
16 I ADC microphone input
MBIAS 17 O Microphone bias output (0.75 V
CCA
)
V
OUT
L 18 O Headphone output for L-channel
V
CCL
19 – Analog power supply for headphone amplifier of L-channel
HGND 20 – Analog ground for headphone amplifier
SBAU132 – March 2008 Description 11
Submit Documentation Feedback