AD7634 Analog Devices, AD7634 Datasheet - Page 9

• 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

Pin No.
8
9
10
11, 12
13
14
15
16
17
18
19
20
21
Mnemonic
D1/A0
D2/A1
D3
D[4:5] or
DIVSCLK[0:1]
D6 or
EXT/INT
D7 or
INVSYNC
D8 or
INVSCLK
D9 or
RDC or
SDIN
OGND
OVDD
DVDD
DGND
D10 or
SDOUT
Type
DI/O
DI/O
DO
DI/O
DO/I
DI/O
DI/O
DI/O
P
P
P
P
DI/O
1
Description
When MODE[1:0] = 0, 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[1:0] = 0, this pin is Bit 2 of the parallel port data output bus.
When MODE[1:0] = 1 or 2, this input pin controls the form in which data is output as shown in Table 7.
When MODE[1:0] = 0, 1, or 2, 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.
When MODE[1:0] = 0, 1, or 2, these pins are Bit 4 and Bit 5 of the parallel port data output bus.
When MODE[1:0] = 3, serial data clock division selection. When using serial master read after convert
mode (EXT/INT = low, RDC/SDIN = low), these inputs can be used to slow down the internally
generated serial clock that clocks the data output. In other serial modes, these pins are high
impedance outputs.
When MODE[1:0] = 0, 1, or 2, this output is used as Bit 6 of the parallel port data output bus.
When MODE[1:0] = 3, Serial Data Clock Source Select. In serial mode, this input is used to select
the internally generated (master) or external (slave) serial data clock for the AD7634 output data.
When EXT/INT = low (master mode), the internal serial data clock is selected on SDCLK output.
When EXT/INT = high (slave mode), the output data is synchronized to an external clock signal (gated by CS)
connected to the SDCLK input.
When MODE[1:0] = 0, 1, or 2, this output is used as Bit 7 of the parallel port data output bus.
When MODE[1:0] = 3, Serial Data Invert Sync Select. In serial master mode (MODE[1:0] = 3,
EXT/INT = low), this input is used to select the active state of the SYNC signal.
When INVSYNC = low, SYNC is active high.
When INVSYNC = high, SYNC is active low.
When MODE[1:0] = 0, 1, or 2, this output is used as Bit 8 of the parallel port data output bus.
When MODE[1:0] = 3, Invert SDCLK/SCCLK Select. This input is used to invert both SDCLK and SCCLK.
When INVSCLK = low, the rising edge of SDCLK/SCCLK are used.
When INVSCLK = high, the falling edge of SDCLK/SCCLK are used.
When MODE[1:0] = 0, 1, or 2, this output is used as Bit 9 of the parallel port data output bus.
When MODE[1:0] = 3, Serial Data Read During Convert. In serial master mode (MODE[1:0] = 3,
EXT/INT = low), RDC is used to select the read mode. See the
When RDC = low, the current result is read after conversion. Note the maximum throughput is not
attainable in this mode.
When RDC = high, the previous conversion result is read during the current conversion.
When MODE[1:0] = 3, Serial Data In. In serial slave mode (MODE[1:0] = 3, EXT/INT = high), SDIN can be
used as a data input to daisy-chain the conversion results from two or more ADCs onto a single SDOUT
line. The digital data level on SDIN is output on SDOUT with a delay of 16 SDCLK periods after the initiation
of the read sequence.
Input/Output Interface Digital Power Ground. Ground reference point for digital outputs. Should be
connected to the system digital ground ideally at the same potential as AGND and DGND.
Input/Output Interface Digital Power. Nominally at the same supply as the supply of the host interface
2.5 V, 3 V, or 5 V and decoupled with 10 μF and 100 nF capacitors.
Digital Power. Nominally at 4.75 V to 5.25 V and decoupled with 10 μF and 100 nF capacitors. Can be
supplied from AVDD.
Digital Power Ground. Ground reference point for digital outputs. Should be connected to system
digital ground ideally at the same potential as AGND and OGND.
When MODE[1:0] = 0, 1, or 2, this output is used as Bit 10 of the parallel port data output bus.
When MODE[1:0] = 3, Serial Data Output. In all serial modes, this pin is used as the serial data output
synchronized to SDCLK. Conversion results are stored in an on-chip register. The AD7634 provides the
conversion result, MSB first, from its internal shift register. The data format is determined by the logic
level of OB/2C.
When EXT/INT = low (master mode), SDOUT is valid on both edges of SDCLK.
When EXT/INT = high (slave mode):
When INVSCLK = low, SDOUT is updated on SDCLK rising edge.
When INVSCLK = high, SDOUT is updated on SDCLK falling edge.
Rev. A | Page 9 of 32
Master Serial Interface
section.
AD7634