AD7634 Analog Devices, AD7634 Datasheet - Page 8

• Manufacturer Part Number: AD7634
• Manufacturer: Analog Devices

Specifications of AD7634

• Resolution (bits): 18bit
• # Chan: 1
• Sample Rate: 670kSPS
• Interface: Byte,Par,Ser,SPI
• Analog Input Type: Diff-Bip,Diff-Uni
• Ain Range: 10V p-p,20 V p-p,40 V p-p
• Adc Architecture: SAR
• Pkg Type: CSP,QFP

AD7634
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Table 6. Pin Function Descriptions
Pin No.
1, 42
2, 44
3, 4
5
6
7
Mnemonic
AGND
AVDD
MODE[0:1]
D0/OB/2C
WARP
IMPULSE
Type
P
P
DI
DI/O
DI
DI
2
2
2
1
Description
Analog Power Ground Pins. Ground reference point for all analog I/O. All analog I/O should be refer-
enced to AGND and should be connected to the analog ground plane of the system. In addition, the
AGND, DGND, and OGND voltages should be at the same potential.
Analog Power Pins. Nominally 4.75 V to 5.25 V and decoupled with 10 μF and 100 nF capacitors.
Data Input/Output Interface Mode Selection.
Interface Mode
0
1
2
3
In 18-bit parallel mode, this output is used as Bit 0 of the parallel port data output bus and the data
coding is straight binary. In all other modes, this pin allows the choice of straight binary or twos
complement.
When OB/2C = high, the digital output is straight binary
When OB/2C = low, the MSB is inverted resulting in a twos complement output from its internal shift
register.
Conversion Mode Selection. See the Modes of Operation section for a more detailed description. Used
in conjunction with the IMPULSE input per the following:
Conversion Mode
Normal
Impulse
Warp
Normal
Conversion Mode Selection. See the WARP pin description in this table. See the Modes of Operation
section for a more detailed description.
NOTES
1. FOR THE LEAD FRAME CHIP SCALE PACKAGE (LFCSP), THE EXPOSED PAD
D4/DIVSCLK[0]
D5/DIVSCLK[1]
SHOULD BE CONNECTED TO VEE. THIS CONNECTION IS NOT REQUIRED TO
MEET THE ELECTRICAL PERFORMANCES.
D0/OB/2C
IMPULSE
MODE0
MODE1
WARP
AGND
D1/A0
AVDD
D2/A1
D3
10
11
12
1
2
3
4
5
6
7
8
9
48 47 46 45 44 43 42 41 40 39 38 37
13 14 15 16 17 18 19 20 21 22 23 24
PIN 1
Figure 4. Pin Configuration
MODE1
Low
Low
High
High
Rev. A | Page 8 of 32
WARP
Low
Low
High
High
(Not to Scale)
TOP VIEW
AD7634
MODE0
Low
High
Low
High
IMPULSE
Low
High
Low
High
Description
18-bit interface
16-bit interface
8-bit (byte) interface
Serial interface
36
35
34
33
32
31
30
29
28
27
26
25
BIPOLAR
CNVST
PD
RESET
CS
RD
TEN
BUSY
D17/SCCS
D16/SCCLK
D15/SCIN
D14/HW/SW