Rainbow Electronics MAX550A - Manual (Page 9)

MAX548A/MAX549A/MAX550A
+2.5V to +5.5V, Low-Power, Single/Dual,
8-Bit Voltage-Output DACs in µMAX Package
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Table 2. MAX548A Serial-Interface Programming Commands
COMMAND
(Commands executed on CS ’s rising edge)
LDAC
COMMANDS LOADING INPUT REGISTER(S) ONLY
X Unassigned operation X XXXXXXXX 0 0 X X X 1 X
X Unassigned command X XXXXXXXX 0 0 X 0 X 0 X
CONTROL BYTE
Loaded First Loaded Last
UB1 Pin 6 D7........D0 A0 A1 C0 C1 UB3 C2 UB2
X
Load DAC B input register and update both DAC
registers. DAC A input register unchanged.
0 8-Bit DAC Data
X
Load DAC A input register and update both DAC
registers. DAC B input register unchanged.
0 8-Bit DAC Data
0 1 1 1 X 0 X
1 0 1 1 X 0 X
Update both DAC registers with current contents
of their input registers. Both input registers
unchanged.
0 0 0 1 1 X 0 X X
X
Load both DAC input registers and update both
DAC registers.
X 8-Bit DAC Data 1 1 0 1 X 0 X
X
Load DAC B input register and update both DAC
registers. DAC A input register unchanged.
X 8-Bit DAC Data 0 1 0 1 X 0 X
X
Load both DAC input registers. Both DAC regis-
ters unchanged.
X 8-Bit DAC Data 1 1 X 0 X 0 X
X
Load DAC B input register. DAC A input register
and both DAC registers unchanged.
X 8-Bit DAC Data 0 1 X 0 X 0 X
X
Load DAC A input register and update both DAC
registers. DAC B input register unchanged.
X 8-Bit DAC Data 1 0 0 1 X 0 X
X
Load DAC A input register. DAC B input register
and both DAC registers unchanged.
Update both DAC registers with current contents
of their input registers. Both input registers
unchanged.
X
X
8-Bit DAC Data
XXXXXXXX
1
0
0
0
X
0
0
1
X 0
X 0
X
X X
UNASSIGNED COMMANDS
DATA BYTE
XXXXXXXX
COMMANDS UPDATING DAC REGISTER(S)
X
Load both DAC input registers and update both
DAC registers.
0 8-Bit DAC Data 1 1 1 1 X 0 X
COMMANDS UTILIZING THE ASYNCHRONOUS LOAD FUNCTION
X
After CS’s rising edge and on LDAC’s falling
edge, update both DAC registers with current
contents of their input registers. Both input regis-
ters unchanged.
1 XXXXXXXX 0 0 1 1 X 0 X
X
Load DAC A input register. After CS’s rising edge
and on LDAC’s falling edge, update both DAC
registers.
1 8-Bit DAC Data 1 0 1 1 X 0 X
X
Load DAC B input register. After CS’s rising edge
and on LDAC’s falling edge, update both DAC
registers.
1 8-Bit DAC Data 0 1 1 1 X 0 X
X
Load both DAC input registers. After CS’s rising
edge and on LDAC’s falling edge, update both
DAC registers.
1 8-Bit DAC Data 1 1 1 1 X 0 X