MAX349 Serially Controlled, Low-Voltage, 8-Channel Dual 4-Channel Multiplexers

Product Details

The MAX349/MAX350 are 8-channel and dual 4-channel serially controlled multiplexers (muxes). These muxes conduct equally well in either direction. On-resistance (100Ω max) is matched between switches to 16Ω max and is flat (10Ω max) over the specified signal range.

These CMOS devices can operate continuously with dual power supplies ranging from ±2.7V to ±8V or a single supply between +2.7V and +16V. Each mux can handle rail-to-rail analog signals. The off-leakage current is only 0.1nA at +25°C or 5nA at +85°C.

Upon power-up, all switches are off and the internal shift registers are reset to zero.

The serial interface is compatible with SPI™/QSPI™ and Microwire™. Functioning as a shift register, it allows data (at DIN) to be clocked in synchronously with the rising edge of clock (SCLK). The shift register's output (DOUT) enables several MAX349s or MAX350s to be daisy chained.

All digital inputs have 0.8V or 2.4V logic thresholds, ensuring both TTL and CMOS-logic compatibility when using ±5V supplies or a single +5V supply.


  • Audio-Signal Routing
  • Automated Test Equipment (ATE)
  • Avionics
  • Industrial and Process Control Systems
  • Networking
  • Serial Data-Acquisition Systems

Features and Benefits

  • SPI/QSPI, Microwire-Compatible Serial Interface
  • 8 Separately Controlled SPST Switches
  • Single 8-to-1 Mux (MAX349)
  • Dual 4-to-1 Mux (MAX350)
  • 100Ω Signal Paths with ±5V Supplies
  • Rail-to-Rail Signal Handling
  • Asynchronous RESET Input
  • ±2.7V to ±8V Dual Supplies
  • +2.7V to +16V Single Supply
  • > 2kV ESD Protection per Method 3015.7
  • TTL/CMOS-Compatible Inputs (with +5V or ±5V Supplies)