
AD7679
PIN CONFIGURATION AND FUNCTIONAL DESCRIPTIONS
Rev. 0 | Page 8 of 28
36
35
34
33
32
31
30
29
28
27
26
25
13 14 15 16 17 18 19 20 21 22 23 24
D
1
2
3
4
5
6
7
8
9
10
11
12
48 47 46 45 44
39 38 37
43 42 41 40
PIN 1
TOPVIEW
(Not to Scale)
AGND
CNVST
PD
RESET
CS
RD
DGND
BUSY
D17
D16
D15
D14
AGND
AVDD
MODE0
MODE1
D0/OB/2C
NC
NC
NC = NO CONNECT
D1/A0
D2/A1
D3
D4/DIVSCLK[0]
D5/DIVSCLK[1]
AD7679
P
A
R
N
A
I
N
N
N
I
R
R
D
D
D
O
O
D
D
D
D
D
D
03085–0–004
Figure 4. 48-Lead LQFP(ST-48) and 48-Lead LFCSP (CP-48)
Table 6. Pin Function Descriptions
Pin No.
Mnemonic
1, 44
AGND
2, 47
AVDD
3
MODE0
4
MODE1
Type
1
P
P
DI
DI
Description
Analog Power Ground Pin.
Input Analog Power Pins. Nominally 5 V.
Data Output Interface Mode Selection.
Data Output Interface Mode Selection:
Interface MODE
0
1
2
3
When MODE = 0 (18-bit interface mode), this pin is Bit 0 of the parallel port data output bus and the
data coding is straight binary. In all other modes, this pin allows choice of straight binary/binary twos
complement. When OB/2C is HIGH, the digital output is straight binary; when LOW, the MSB is
inverted, resulting in a twos complement output from its internal shift register.
No Connect.
MODE1
0
0
1
1
MODE0
0
1
0
1
Description
18-Bit Interface
16-Bit Interface
Byte Interface
Serial Interface
5
D0/OB/2C
DI/O
6, 7, 40–
42, 45
8
NC
D1/A0
DI/O
When MODE = 0 (18-bit interface mode), this pin is Bit 1 of the parallel port data output bus. In all
other modes, this input pin controls the form in which data is output, as shown in Table 7.
When MODE = 0 or 1 (18-bit or 16-bit interface mode), this pin is Bit 2 of the parallel port data output
bus. In all other modes, this input pin controls the form in which data is output, as shown in Table 7.
In all modes except MODE = 3, this output is used as Bit 3 of the parallel port data output bus. This pin
is always an output, regardless of the interface mode.
In all modes except MODE = 3, these pins are Bit 4 and Bit 5 of the parallel port data output bus.
When MODE = 3 (serial mode), EXT/INT is LOW, and RDC/SDIN is LOW (serial master read after
convert), these inputs, part of the serial port, are used to slow down, if desired, the internal serial clock
that clocks the data output. In other serial modes, these pins are not used.
In all modes except MODE = 3, this output is used as Bit 6 of the parallel port data output bus.
When MODE = 3 (serial mode), this input, part of the serial port, is used as a digital select input for
choosing the internal data clock or an external data clock. With EXT/INT tied LOW, the internal clock is
selected on the SCLK output. With EXT/INT set to a logic HIGH, output data is synchronized to an
external clock signal connected to the SCLK input.
9
D2/A1
DI/O
10
D3
DO
11, 12
D[4:5]or
DIVSCLK[0:1]
DI/O
13
D6
or EXT/INT
DI/O