Datasheet

AD7908/AD7918/AD7928
Rev. D | Page 25 of 32
CS
SCLK
DOUT
DIN
THREE-STATE THREE-STATE
FOUR TRAILING ZEROS
ZERO
B
123456
11 12 13 14 15 16
WRITE SEQ1 DONTC ADD2 ADD1 ADD0
ADD2 ADD1 ADD0 DB7 DB6 DB0 ZERO ZERO ZERO ZERO
CODING
DONTC DONTC DONTC DONTC
t
5
t
8
t
11
t
QUIET
t
9
t
3
t
2
t
4
t
7
t
6
t
CONVERT
t
10
0
3089-026
THREE IDENTIFICATION BITS
Figure 26. AD7908 Serial Interface Timing Diagram
CS
SCLK
DOUT
DIN
THREE-STATE THREE-STATE
TWO TRAILING ZEROS
ZERO
B
123456
11 12 13 14 15 16
WRITE SEQ DONTC ADD2 ADD1 ADD0
ADD2 ADD1 ADD0 DB7 DB6 DB2 DB1 DB0 ZERO ZERO
CODING
DONTC DONTC DONTC DONTC
t
5
t
8
t
11
t
QUIET
t
9
t
3
t
2
t
4
t
7
t
6
t
CONVERT
t
10
03089-027
THREE IDENTIFICATION BITS
Figure 27. AD7918 Serial Interface Timing Diagram
B
ZERO
CS
SCLK
DOUT
DIN
THREE-STATE
THREE-STATE
123456
13
14 15
16
WRITE SEQ DONTC ADD2 ADD1 ADD0
DB2 DB1 DB0
DONTCDONTC DONTC
t
5
t
8
t
11
t
QUIET
t
9
t
3
t
2
t
7
t
4
t
6
t
CONVERT
t
10
ADD2 ADD1 ADD0 DB11 DB10
0
3089-028
THREE IDENTIFICATION BITS
Figure 28. AD7928 Serial Interface Timing Diagram
C
ZERO
CS
SCLK
DOUT
DIN
THREE-STATE
THREE-STATE
THREE IDENTIFICATION BITS
t
5
t
8
t
11
t
9
t
3
t
2
t
7
t
4
t
6
t
CONVERT
t
10
ADD2 ADD1 ADD0 DB11 DB10 DB2 DB1 DB0
123456
13
14 15
16
SEQUENCE 1 SEQUENCE 2
V
IN
0V
IN
1V
IN
2V
IN
3V
IN
4V
IN
5V
IN
6V
IN
7
0
3089-029
Figure 29. AD7928 Writing to SHADOW Register Timing Diagram