max5134 Maxim Integrated Products, Inc., max5134 Datasheet - Page 9

• Manufacturer Part Number: max5134
• Description: Low-power, Quad 16-bit, Buffered Voltage-output Dac
• Manufacturer: Maxim Integrated Products, Inc.

The MAX5134 low-power, quad 16-bit, digital-to-analog
converter (DAC) uses a precision internal reference or
an external reference for rail-to-rail operation to provide
high-linearity buffered voltage outputs. The MAX5134
minimizes the digital noise feedthrough from input to out-
put by powering down the SCLK and DIN input buffers
after completion of each 24-bit serial input. On power-
up, the MAX5134 resets the DAC outputs to zero or mid-
scale, 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 contains a segmented resistor string-type
DAC, a serial-in parallel-out shift register, a DAC regis-
ter, 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.
2, 5, 8, 11,
14, 17, 20,
7, 19
PIN
23
10
12
13
15
16
18
21
22
24
—
1
3
4
6
9
READY
NAME
DVDD
AVDD
OUT0
OUT3
SCLK
OUT2
LDAC
OUT1
REFO
GND
N.C.
REFI
DIN
M/Z
CS
EP
_______________________________________________________________________________________
Detailed Description
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
Seria-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.
Buffered Voltage-Output DAC
Low-Power, Quad 16-Bit,
The MAX5134 includes internal buffers for all DAC out-
puts. The internal buffers provide improved load regula-
tion 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 features 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 resis-
tor with a 1µF capacitor to ground. REFO can deliver up
to 100µA of current with no degradation in perfor-
mance. Configure other reference voltages 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
9