7.4.1.1.2 External Reference
By default, the DACx3202 operate from an external reference input. The external reference option can also be
selected by configuring the VOUT-GAIN-X field in the DAC-X-VOUT-CMP-CONFIG register appropriately. Write
1 to the DIS-MODE-IN bit in the DEVICE-MODE-CONFIG register to minimize I
DD
. The external reference can
be between 1.7 V and VDD.
shows DAC transfer function when the external reference is used. The
gain at the output stage of the DAC is always 1x in the external reference mode.
Note
The external reference must be less than VDD in both transient and steady-state conditions.
Therefore, the external reference must ramp up after VDD and ramp down before VDD.
V
OUT
=
DAC_DATA
2N
× V
REF
(2)
where:
• N is the resolution in bits, 10 (DAC53202), or 12 (DAC63202).
• DAC_DATA is the decimal equivalent of the binary code that is loaded to the DAC-X-DATA field in the
DAC-X-DATA register. DAC_DATA ranges from 0 to 2
N
– 1.
• V
REF
is the external reference voltage.
7.4.1.1.3 Power-Supply as Reference
The DACx3202 can operate with the power-supply pin (VDD) as a reference.
function when the power-supply pin is used as reference. The gain at the output stage is always 1x.
V
OUT
=
DAC_DATA
2N
× V
DD
(3)
where:
• N is the resolution in bits, either 10 (DAC53202), or 12 (DAC63202).
• DAC_DATA is the decimal equivalent of the binary code that is loaded to the DAC-X-DATA bit in the
DAC-X-DATA register.
• DAC_DATA ranges from 0 to 2
N
– 1.
• V
DD
is used as the DAC reference voltage.
7.4.2 Current-Output Mode
To enter current-output mode for each DAC channel, disable the respective IOUT-PDN-X bits in the COMMON-
CONFIG register, and set the respective VOUT-PDN-X bits in the same register to Hi-Z power-down mode.
Select the desired current-output range by writing to the IOUT-RANGE-X bit in the DAC-X-IOUT-MISC-CONFIG
register. To minimize leakage in current-output mode, disconnect the FBx pin. For the best power-on glitch
performance, program the NVM with IOUT mode using the smallest output range before powering on the output
channel, and then immediately program the DAC code and desired output range. The transfer function of the
output current is shown in
I
OUT
=
DAC_DATA × IMAX − IMIN
28
+ I
MIN
(4)
where:
• DAC_DATA is the decimal equivalent of the binary code that is loaded to the DAC-X-DATA bit as specified in
. DAC_DATA ranges from 0 to 255.
• I
MAX
is the signed maximum current in the IOUT-RANGE-X setting as specified in
• I
MIN
is the signed minimum current in the IOUT-RANGE-X setting as specified in
.
SLASF47 – MAY 2022
28
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