+5V, Serial-Input, Voltage-Output, 14-Bit DACs
MAX544/MAX545
+5V
+2.5V
10µF
0.1µF
0.1µF
MC68XXXX
PCS0
MOSI
SCLK
(GND)
CS
DIN
SCLK
V
DD
REF (REFF)
(REFS)
UNIPOLAR
OUT
MAX495
MAX544/MAX545
OUT
EXTERNAL OP AMP
(
LDAC
)
DGND
AGND_
( ) ARE FOR MAX545 ONLY
Figure 2a. Typical Operating Circuit—Unipolar Output
+5V
+2.5V
10µF
0.1µF
0.1µF
+5V
MC68XXXX
PCS0
MOSI
SCLK
IC1
(GND)
CS
DIN
V
DD
REFF
REFS
R
INV
R
FB
RFB
INV
MAX400
OUT
BIPOLAR
OUT
EXTERNAL OP AMP
SCLK
LDAC
DGND
MAX545
-5V
AGNDF
AGNDS
Figure 2b. Typical Operating Circuit—Bipolar Output
Detailed Description
The MAX544/MAX545 voltage-output, 14-bit digital-to-
analog converters (DACs) offer full 14-bit performance
with less than 0.5LSB integral linearity error and less
than 0.9LSB differential linearity error, thus ensuring
monotonic performance. Serial-data transfer minimizes
the number of package pins required.
The MAX544/MAX545 are composed of two matched
DAC sections, with an inverted R-2R DAC forming the
LSBs and the four MSBs derived from 15 identically
matched resistors. This architecture allows the lowest
glitch energy to be transferred to the DAC output on
major-carry transitions. It also lowers the DAC output
impedance by a factor of eight compared to a standard
R-2R ladder, allowing unbuffered operation in medium-
load applications.
The MAX545 provides matched bipolar offset resistors,
which connect to an external op amp for bipolar output
swings (Figure 2b). For optimum performance, the
MAX545 also provides a set of Kelvin connections to
the voltage-reference and analog-ground inputs.
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
