MAX5132/MAX5133
+5V/+3V, 13-Bit, Serial, Force/Sense DACs
with 10ppm/°C Internal Reference
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where NB is the numeric value of the DAC’s binary
input code, V
REF
is the voltage of the internal (or exter-
nal) precision reference, and G is the overall gain. The
application circuit in Figure 10 uses a low-cost op amp
(MAX4162) external to the MAX5132/MAX5133.
Together with the MAX5132/MAX5133, this circuit offers
an overall gain of 2V/V. Table 6 lists example codes for
bipolar output voltages.
Reset (RSTVAL) and
Clear (
CCLLRR
) Functions
The MAX5132/MAX5133 DACs feature a clear pin
(CLR), which resets the output to a certain value,
depending upon how RSTVAL is set. RSTVAL = DGND
selects an output of 0, and RSTVAL = V
DD
selects a
midscale output when CLR is pulled low.
The CLR pin has a minimum input resistance of 40kΩ in
series with a diode to the supply voltage (V
DD
). If the
digital voltage is higher than the supply voltage for the
part, a small input current may flow, but this current will
be limited to (V
CLR
- V
DD
- 0.5V) / 40kΩ.
Note: Clearing the DAC will also cause the part to exit
software shutdown (PD = 0).
Daisy-Chaining Devices
Any number of MAX5132/MAX5133s may be daisy-
chained simply by connecting the serial data output pin
(DOUT) of one device to the serial data input pin (DIN)
of the following device in the chain (Figure 11).
Another configuration (Figure 12) allows several
MAX5132/MAX5133 DACs to share one common DIN
signal line. In this configuration, the data bus is com-
mon to all devices; data is not shifted through a daisy
chain. However, more I/O lines are required in this con-
figuration because each IC needs a dedicated CS line.
