AD9945 Analog Devices, AD9945 Datasheet - Page 9

• Manufacturer Part Number: AD9945
• Description: Complete 12-Bit 40 MHz CCD Signal Processor
• Manufacturer: Analog Devices

SERIAL INTERFACE
REV. A
SDATA
SDATA
SCK
SL
SCK
SL
NOTES
1. MULTIPLE SEQUENTIAL REGISTERS MAY BE LOADED CONTINUOUSLY.
2. THE FIRST (LOWEST ADDRESS) REGISTER ADDRESS IS WRITTEN, FOLLOWED BY MULTIPLE 12-BIT DATA-WORDS.
3. THE ADDRESS WILL AUTOMATICALLY INCREMENT WITH EACH 12-BIT DATA-WORD (ALL 12 BITS MUST BE WRITTEN).
4. SL IS HELD LOW UNTIL THE LAST DESIRED REGISTER HAS BEEN LOADED.
5. NEW DATA IS UPDATED AT THE NEXT SL RISING EDGE.
t
DS
A0
NOTES
1. SDATA BITS ARE INTERNALLY LATCHED ON THE RISING EDGES OF SCK.
2. SYSTEM UPDATE OF LOADED REGISTERS OCCURS ON SL RISING EDGE.
3. ALL 12 DATA BITS D0 TO D11 MUST BE WRITTEN. IF THE REGISTER CONTAINS FEWER THAN 12 BITS, ZEROS SHOULD BE
4. TEST BIT IS FOR INTERNAL USE ONLY. MUST BE SET LOW.
1
USED FOR THE UNDEFINED BITS.
A1
A0
2
t
A2
LS
A1
3
t
TEST
DH
BIT
0
Figure 5. Continuous Serial Write Operation to All Registers
4
A2
D0
5
TEST BIT
D1
DATA FOR STARTING
0
REGISTER ADDRESS
6
D2
D0
7
Figure 4. Serial Write Operation
D3
8
D1
D4
9
D2
D5
10
D3
...
...
...
–9–
D4
D10
15
D11
D5
16
D0
D6
17
D1
REGISTER ADDRESS
18
DATA FOR NEXT
D7
...
...
...
D8
D10 D11
D9
27
28
D10
t
D0
LH
29
D11
D1
30
D2
AD9945
31
...
...
...