MAX11311 Datasheet, PDF (26/51 Pages) Maxim Integrated Products – PIXI, 12-Port Programmable Mixed-Signal I/O with 12-Bit ADC, 12-Bit DAC, Analog Switches, and GPIO

MAX11311
PIXI, 12-Port Programmable Mixed-Signal I/O with
12-Bit ADC, 12-Bit DAC, Analog Switches, and GPIO
Internally or Externally Controlled
Analog Switch Operation
Two adjacent PIXI ports from the same group of ports
(PORT0 to PORT5 or PORT6 to PORT11) can form
a 60Ω analog switch that is controlled by two different
configurations. Analog switches cannot be configured
between programmable ports in different groups, such
as between PORT5 and PORT6 or between PORT0
and PORT11. In one configuration, the switch is dynamically
controlled by any other GPI-configured PIXI port, as
illustrated in Figure 12. The signal applied to that GPI-
configured port can be inverted.
In the other configuration, the switch is programmed to be
permanently “ON” by configuring the corresponding PIXI
port. To turn the switch “OFF”, the host must set that PIXI
port in high-impedance configuration.
Power-Supply Brownout Detection
The MAX11311 features a brownout detection circuit that
monitors AVDDIO and AVDD pins. When AVDDIO goes
below approximately 4.0V, an interrupt is registered, and
the interrupt port is asserted if not masked. When AVDD
goes below approximately 4.0V, the device resets.
SPI Operations
The MAX11311 SPI interface complies with the timing
of Mode 0, as illustrated in Figure 13. The MAX11311
samples incoming data on the rising edge of SCLK and
releases outgoing data on the falling edge of SCLK.
PIXI PORT[i]
Figure 12. PIXI Ports as a Controllable Analog Switch
GPI ANY OTHER PORT
PIXI PORT[i+1]
SCLK
DIN
B23
B22
B21
DOUT
CS
B23
B22
B21
Figure 13. SPI Timing (Mode 0)
B3
B2
B1
B0
B3
B2
B1
B0
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