max5520etc Maxim Integrated Products, Inc., max5520etc Datasheet - Page 12

• Manufacturer Part Number: max5520etc
• Description: +1.8v To +5.5v, Ultra-low-power, 10-bit, Voltage-output Dacs
• Manufacturer: Maxim Integrated Products, Inc.

The MAX5520/MAX5521 single, 10-bit, ultra-low-power,
voltage-output DACs offer Rail-to-Rail buffered voltage
outputs. The DACs operate from a 1.8V to 5.5V supply
and require only 6µA (max) supply current. These
devices feature a shutdown mode that reduces overall
current, including the reference input current, to just
0.18µA. The MAX5521 includes an internal reference
that saves additional board space and can source up
to 8mA, making it functional as a system reference. The
16MHz, 3-wire serial interface is compatible with SPI,
QSPI, and MICROWIRE protocols. When V
applied, all DAC outputs are driven to zero scale with
virtually no output glitch. The MAX5520/MAX5521 out-
put buffers are configured in force sense allowing users
to externally set voltage gains on the output (an output-
amplifier inverting input is available). These devices
come in a 4mm x 4mm thin QFN package.
+1.8V to +5.5V, Ultra-Low-Power, 10-Bit,
Voltage-Output DACs
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SCLK
DIN
CS
Detailed Description
CONTROL
CONTROL
REGISTER
POWER-
DOWN
LOGIC
SHIFT
AND
REGISTER
INPUT
PROGRAMMABLE
V
DD
GND
REFERENCE
DD
2-BIT
is
MAX5521
REGISTER
DAC
The MAX5520/MAX5521 use a 3-wire serial interface
compatible with SPI, QSPI, and MICROWIRE protocols
(Figures 1 and 2).
The MAX5520/MAX5521 include a single, 16-bit, input
shift register. Data loads into the shift register through
the serial interface. CS must remain low until all 16 bits
are clocked in. Data loads MSB first, D9–D0. The 16
bits consist of 4 control bits (C3–C0), 10 data bits
(D9–D0), and 2 sub-bits (see Table 1). D9–D0 are the
DAC data bits and S1 and S0 are the sub-bits. The
sub-bits must be set to zero for proper operation. The
control bits C3–C0 control the MAX5520/MAX5521, as
outlined in Table 2.
Each DAC channel includes two registers: an input reg-
ister and a DAC register. The input register holds input
data. The DAC register contains the data updated to
the DAC output.
The double-buffered register configuration allows any
of the following:
• Loading the input registers without updating the DAC
• Updating the DAC registers from the input registers
• Updating all the input and DAC registers simultaneously
registers
BUF
REF
10-BIT DAC
MAX5521 Functional Diagram
REFOUT
OUT
FB
Digital Interface