MAX5137 Maxim Integrated Products, MAX5137 Datasheet - Page 9

• Manufacturer Part Number: MAX5137
• Description: (MAX5134 - MAX5137) Voltage-Output DACs
• Manufacturer: Maxim Integrated Products

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The MAX5134–MAX5137 is a family of pin-compatible
and software-compatible 16-bit and 12-bit DACs. The
MAX5134/MAX5135 are low-power, quad 16-/12-bit,
buffered voltage-output, high-linearity DACs. The
MAX5136/MAX5137 are low-power, dual 16-/12-bit,
buffered voltage-output, high-linearity DACs. The
MAX5134–MAX5137 minimize the digital noise
feedthrough from input to output by powering down the
SCLK and DIN input buffers after completion of each 24-
bit serial input. On power-up, the MAX5134–MAX5137
reset the DAC outputs to zero or midscale, depending
on the state of the M/Z input, providing additional safety
for applications that drive valves or other transducers
that need to be off on power-up. The MAX5134–
MAX5137 contain a segmented resistor string-type DAC, a
serial-in parallel-out shift register, a DAC register, power-
on reset (POR) circuit, and control logic. On the falling
edge of the clock (SCLK) pulse, the serial input (DIN) data
is shifted into the device, MSB first. During power-down,
an internal 80kΩ resistor pulls DAC outputs to GND.
11, 14, 17,
MAX5134
MAX5135
2, 5, 8,
20, 23
7, 19
10
12
13
15
16
18
21
22
24
—
1
3
4
6
9
PIN
11, 13, 14,
MAX5136
MAX5137
17, 20, 23
2, 5, 6, 8,
7, 19
—
10
12
—
15
16
18
21
22
24
—
1
3
4
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Detailed Description
READY
NAME
DVDD
AVDD
OUT0
OUT3
SCLK
OUT2
LDAC
OUT1
REFO
GND
N.C.
REFI
DIN
M/Z
CS
EP
Channel 0 Buffered DAC Output
No Connection. Not internally connected.
Digital Power Supply. Bypass DVDD with a 0.1µF capacitor to GND.
Active-Low Ready. Indicated configuration ready. Use READY as CS for consecutive part
or as feedback to the µC.
Channel 3 Buffered DAC Output
Ground
Data In
Active-Low Chip-Select Input
Serial-Clock Input
Channel 2 Buffered DAC Output
Load DAC Input. Active-low hardware load DAC input.
Power-Up Reset Select. Connect M/Z to DVDD to power up the DAC outputs to midscale.
Connect M/Z to GND to power up the DAC outputs to zero.
Channel 1 Buffered DAC Output
Reference Voltage Output
Reference Voltage Input. Bypass REFI with a 0.1µF capacitor to GND when using external
reference.
Analog Power Supply. Bypass AVDD with a 0.1µF capacitor to GND.
Exposed Pad. Internally connected to GND. Connect to a large ground plane to maximize
thermal performance. Not intended as an electrical connection point.
16-/12-Bit, Voltage-Output DACs
Pin-/Software-Compatible,
The MAX5134–MAX5137 include internal buffers for all
DAC outputs. The internal buffers provide improved load
regulation and transition glitch suppression for the DAC
outputs. The output buffers slew at 1.25V/µs and drive up
to 2kΩ in parallel with 200pF. The analog supply voltage
(AVDD) determines the maximum output voltage range
of the device as AVDD powers the output buffers.
The MAX5134–MAX5137 feature an internal reference
with a nominal output of +2.44V. Connect REFO to REFI
when using the internal reference. Bypass REFO to
GND with a 47pF (maximum 100pF) capacitor.
Alternatively if heavier decoupling is required, use a
1kΩ series resistor with a 1µF capacitor to ground.
REFO can deliver up to 100µA of current with no degra-
dation in performance. Configure other reference volt-
ages by applying a resistive potential divider with a
total resistance greater than 33kΩ from REFO to GND.
FUNCTION
Output Amplifiers (OUT0–OUT3)
Pin Description
DAC Reference
Internal Reference
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