Table 7. select bits programming example – Rainbow Electronics MAX5295 User Manual
Page 21
MAX5290–MAX5295
Buffered, Fast-Settling, Dual, 12-/10-/8-Bit,
Voltage-Output DACs
______________________________________________________________________________________
21
Default register values at power-up correspond to the
state of PU, e.g. input and DAC registers are set to
800hex if PU is floating, FFFhex if PU = DV
DD
, and
000hex if PU= DGND.
DAC Programming Examples:
To load input register A from the shift register, leaving
DAC register A unchanged (DAC output unchanged),
use the command in Table 3.
The MAX5290–MAX5295 can load DAC register A from
the shift register, leaving input register A unchanged,
by using the command in Table 4.
To load input register A and DAC register A simultane-
ously from the shift register, use the command in Table 5.
For the 10-bit and 8-bit versions, set sub-bits = 0 for
best performance.
Advanced Feature
Programming Commands
Refer to the Programmer’s Handbook for details.
Select Bits (MA, MB)
The select bits allow synchronous updating of any com-
bination of channels. The select bits command the
loading of the DAC register from the input register of
each channel. Set the select bit M_ = 1 to load the DAC
register “_” with data from the input register “_”, where
“_” is replaced with A or B depending on the selected
channel. Setting the select bit to M_ = 0 results in no
action for that channel (Table 6).
Table 3. Load Input Register A from Shift Register
Table 4. Load DAC Register A from Shift Register
Table 5. Load Input Register A and DAC Register A from Shift Register
Table 6. Select Command
DATA
CONTROL BITS
DATA BITS
DIN
0
0
0
0
D11
D10
D9
D8
D7
D6
D5
D4
D3/0
D2/0
D1/0
D0/0
DATA
CONTROL BITS
DATA BITS
DIN
0
0
0
1
D11
D10
D9
D8
D7
D6
D5
D4
D3/0
D2/0
D1/0
D0/0
DATA
CONTROL BITS
DATA BITS
DIN
0
0
1
0
D11
D10
D9
D8
D7
D6
D5
D4
D3/0
D2/0
D1/0
D0/0
DATA
CONTROL BITS
DATA BITS
DIN
1
1
1
0
0
0
X
X
X
X
X
X
X
X
MB
MA
Table 7. Select Bits Programming Example
DATA
CONTROL BITS
DATA BITS
DIN
1
1
1
0
0
0
X
X
X
X
X
X
X
X
1
0
X = Don’t care.
X = Don’t care.