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

______________________________________________________________________________________

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

, 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

D11

D10

D3/0

D2/0

D1/0

D0/0

DATA

CONTROL BITS

DATA BITS

DIN

D11

D10

D3/0

D2/0

D1/0

D0/0

DATA

CONTROL BITS

DATA BITS

DIN

D11

D10

D3/0

D2/0

D1/0

D0/0

DATA

CONTROL BITS

DATA BITS

DIN

Table 7. Select Bits Programming Example

DATA

CONTROL BITS

DATA BITS

DIN

X = Don’t care.