AD7892
Pin
No.
Mnemonic
Description
16
DB4/SCLK
Data Bit 4/Serial Clock. When the device is in its parallel mode, this pin is Data Bit 4, a three-state
TTL-compatible output. When the device is in its serial mode, this becomes the serial clock pin,
SCLK. SCLK is an input and an external serial clock must be provided at this pin to obtain serial
data from the AD7892. Serial data is clocked out from the output shift register on the rising edges
of SCLK after RFS goes low.
17
DB3/RFS
Data Bit 3/Receive Frame Synchronization. When the device is in its parallel mode, this pin is Data
Bit 3, a three-state TTL-compatible output. When the device is in its serial mode, this becomes the
receive frame synchronization input with RFS provided externally to obtain serial data from the
AD7892.
18
19
20
DB2
DB1
DB0
Data Bit 2. Three-state TTL-compatible output. This output should be left unconnected when the
device is in its serial mode.
Data Bit 1. Three-state TTL-compatible output. This output should be left unconnected when the
device is in its serial mode.
Data Bit 0 (LSB). Three-state TTL-compatible output. Output coding is two’s complement for
AD7892-1 and AD7892-3 and straight (natural) binary for AD7892-2. This output should be left
unconnected when the device is in its serial mode.
21
22
23
RD
Read. Active low logic input which is used in conjunction with CS low to enable the data outputs.
Chip Select. Active low logic input which is used in conjunction with RD to enable the data outputs.
CS
EOC
End-of-Conversion. Active low logic output indicating converter status. The end of conversion is
signified by a low going pulse on this line. The duration of this EOC pulse is nominally 100 ns.
24
CONVST
Convert Start. Logic Input. A low-to-high transition on this input puts the track/hold into its hold
mode and starts conversion.
PIN CONFIGURATION
DIP and SOIC
V
1
2
3
4
5
6
7
8
9
24 CONVST
23 EOC
DD
STANDBY
V
V
22 CS
IN2
IN1
21 RD
REF OUT/REF IN
AGND
20 DB0 (LSB)
19 DB1
AD7892
TOP VIEW
(Not to Scale)
MODE
18 DB2
DB11/LOW
DB10/LOW
17 DB3/RFS
DB4/SCLK
16
15 DB5/SDATA
14
DB9 10
DB8 11
DB7 12
DGND
13 DB6
–7–
REV. C
ADI [ ADI ]
