Datasheet
MAX5308/MAX5309
Shutdown Modes
The MAX5308/MAX5309 include three software-con-
trolled shutdown modes that reduce the supply current
to less than 1µA. In two of the three shutdown modes
(shutdown 2 and 3) the outputs are independently con-
nected to ground through a 1kΩ or 100kΩ (default)
resistor. The third shutdown (shutdown 1) command
leaves the DACs outputs high impedance. Table 2 lists
the three shutdown modes of operation as well as the
power-up command.
Serial-Data Output (DOUT)
The DOUT (MAX5308) follows DIN with a 16 clock
cycle delay. The DOUT is capable of driving 20pF load
with a 50ns (max) delay from the falling edge of SCLK.
DOUT is primarily used for daisy-chaining multiple
devices. Optionally, DOUT can be used to monitor the
serial interface for valid communications by connecting
DOUT to a microprocessor input.
Hardware Clear (CLR)
The MAX5309 has an active-low CLR input. Drive CLR
low to clear all internal registers, shutdown all DACs,
Low-Power, Low-Glitch, Octal 10-Bit Voltage-
Output DACs with Serial Interface
10 ______________________________________________________________________________________
CONTROL BITS DATA BITS
C3 C2 C1 C0 DAC
8
DAC
7
DAC
6
DAC
5
DAC
4
DAC
3
DAC
2
DAC
1
D03 D02 D01 D00 DESC. FUNCTION
1111 1 1 X XPower-
Up
Power-Up individual DAC
buffers indicated by data in
DAC1 through DAC8. A one
indicates the DAC output is
connected and active. A zero
does not affect the DACs
present state.
1111 0 1 X XShut-
down 1
Shutdown individual DAC
buffers indicated by data in
DAC1 through DAC8. A one
indicates the DAC output is
high-impedance. A zero
does not affect the DACs’
present state.
1111 1 0 X XShut-
down 2
Shutdown individual DAC
buffers indicated by data in
DAC1 through DAC8. A one
indicates the DAC is shutdown
and the output is connected
to GND through a 1kΩ resistor.
A zero does not affect the
DACs present state.
1111 0 0 X XShut-
down 3
Shutdown individual DAC
buffers indicated by data in
DAC1 through DAC8. A one
indicates the DAC is shutdown
and the output is connected
to GND through a 100kΩ
resistor. A zero does not affect
the DACs present state.
Table 2. Serial Interface Power-Up and Shutdown Commands
X = Don’t Care