Serially Controlled, Low-Voltage,

8-Channel/Dual 4-Channel Multiplexers

16

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SCLK

DIN

DOUT

CS

SK

SO

SI

I/O

MICROWIRE

PORT

MAX349

MAX350

THE DOUT-SI CONNECTION IS NOT REQUIRED FOR WRITING TO THE

MAX349/MAX350, BUT MAY BE USED FOR DATA-ECHO PURPOSES.

Figure 3. Connections for MICROWIRE

DOUT

DIN

SCLK

CS

MISO

MOSI

SCK

I/O

SPI

PORT

MAX349

MAX350

THE DOUT-MISO CONNECTION IS NOT REQUIRED FOR WRITING TO THE

MAX349/MAX350, BUT MAY BE USED FOR DATA-ECHO PURPOSES.

CPOL = 0, CPHA = 0

Figure 4. Connections for SPI and QSPI

SCLK

DIN

CS

MAX349

MAX350

SCLK

DIN

CS

MAX349

MAX350

SCLK

DIN

CS

MAX349

MAX350

DOUT

DOUT

DOUT

SCLK

DIN

CS

TO OTHER

SERIAL DEVICES

Figure 5. Daisy-Chained Connection

Dual, Differential 4-Channel Multiplexer

The MAX350 can be programmed normally, with only

one differential channel selected for every eight clock

pulses, or it can be programmed in a fast mode, where

channel changing occurs on each clock pulse.

In fast mode, select the channels by sending two high

pulses, spaced four clock pulses apart (corresponding

to the two selected channels) at DIN, and a corre-

sponding CS low pulse for each of the first eight clock

pulses. As SCLK clocks this through the register, each

switch sequences one differential channel at a time,

starting with channel 0. Repeat this process for subse-

quent channel sequencing after the first eight bits have

been sent. For even faster channel sequencing, send

only one DIN high pulse and one CS low pulse for

every four clock pulses.

Reset Function

RESET is the internal reset pin. It is usually connected

to a logic signal or V+. Drive RESET low to open all

switches and set the contents of the internal shift regis-

ter to zero simultaneously. When RESET is high, the

part functions normally and DOUT is sourced from V+.

RESET must not be driven beyond V+ or GND.