Datasheet

AD9837
Data Sheet
Rev. A | Page 18 of 28
NO
WRITE 14 MSBs OR LSBs
TO A FREQUENCY REGISTER?
(CONTROL REGISTER WRITE)
B28 (D13) = 0
HLB (D12) = 0/1
WRITE A 16-BIT WORD
(SEE TABLE 11 AND TABLE 12
FOR EXAMPLES)
WRITE 14 MSBs OR LSBs
TO A
FREQUENCY REGISTER?
WRITE TO PHASE
REGISTER?
(16-BIT WRITE)
D15, D14 = 11
D13 = 0/1 (CHOOSE THE
PHASE REGISTER)
D12 = X
D11 ... D0 = PHASE DATA
WRITE TO ANOTHER
PHASE REGISTER?
YES
WRITE ANOTHER FULL
28-BIT WORD TO A
FREQUENCY REGISTER?
WRITE TWO CONSECUTIVE
16-BIT WORDS
(SEE TABLE 10 FOR EXAMPLE)
(CONTROL REGISTER WRITE)
B28 (D13) = 1
WRITE A FULL 28-BIT WORD
TO A FREQUENCY REGISTER?
DATA WRITE
NO
YES
YES
NO
YES
ONON
YES
YES
09070-028
Figure 24. Flowchart for Data Writes