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AD6655
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
Rev. 0 | Page 19 of 84
1
D
1
D
1
D
2
D
2
D
2
D
2
D
2
D
2
D
2
D
2
D
2
D
2
F
3
F
3
F
3
F
6
6
6
6
6
5
5
5
5
5
5
5
5
5
5
4
D
D
D
D
D
D
D
D
F
F
F
F
S
C
C
C
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
DRVDD
D6B
D7B
D8B
D9B
D10B
D11B
D12B
D13B (MSB)
DCOB
DCOA
D0A (LSB)
D1A
D2A
D3A
D4A
SCLK/DFS
SDIO/DCS
AVDD
AVDD
VIN+B
VIN–B
RBIAS
CML
SENSE
VREF
VIN–A
VIN+A
AVDD
SMI SDFS
SMI SCLK/PDWN
SMI SDO/OEB
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
PIN 1
INDICATOR
AD6655
PARALLEL CMOS
TOP VIEW
(Not to Scale)
EXPOSED PADDLE, PIN 0
(BOTTOM OF PACKAGE)
0
Figure 9. LFCSP Parallel CMOS Pin Configuration (Top View)
Table 12. Pin Function Descriptions (Parallel CMOS Mode)
Pin No.
Mnemonic
ADC Power Supplies
20, 64
DRGND
1, 21
DRVDD
24, 57
DVDD
36, 45, 46
AVDD
0
AGND
ADC Analog
37
VIN+A
38
VINA
44
VIN+B
43
VINB
39
VREF
40
SENSE
42
RBIAS
41
CML
49
CLK+
50
CLK
ADC Fast Detect Outputs
29
FD0A
30
FD1A
31
FD2A
32
FD3A
53
FD0B
54
FD1B
55
FD2B
56
FD3B
Digital Input
52
SYNC
Type
Description
Ground
Supply
Supply
Supply
Ground
Digital Output Ground.
Digital Output Driver Supply (1.8 V to 3.3 V).
Digital Power Supply (1.8 V Nominal).
Analog Power Supply (1.8 V Nominal).
Analog Ground. Pin 0 is the exposed thermal pad on the bottom of the package.
Input
Input
Input
Input
Input/Output
Input
Input/Output
Output
Input
Input
Differential Analog Input Pin (+) for Channel A.
Differential Analog Input Pin () for Channel A.
Differential Analog Input Pin (+) for Channel B.
Differential Analog Input Pin () for Channel B.
Voltage Reference Input/Output.
Voltage Reference Mode Select. (See Table 15 for details.)
External Reference Bias Resistor.
Common-Mode Level Bias Output for Analog Inputs.
ADC Clock Input—True.
ADC Clock Input—Complement.
Output
Output
Output
Output
Output
Output
Output
Output
Channel A Fast Detect Indicator. (See Table 21 for details.)
Channel A Fast Detect Indicator. (See Table 21 for details.)
Channel A Fast Detect Indicator. (See Table 21 for details.)
Channel A Fast Detect Indicator. (See Table 21 for details.)
Channel B Fast Detect Indicator. (See Table 21 for details.)
Channel B Fast Detect Indicator. (See Table 21 for details.)
Channel B Fast Detect Indicator. (See Table 21 for details.)
Channel B Fast Detect Indicator. (See Table 21 for details.)
Input
Digital Synchronization Pin. Slave mode only.