Fault-Protected, High-Voltage Single 8-to-1/Dual 4-to-1 Multiplexers with Output Clamps

The MAX4508/MAX4509 are 8-to-1 and dual 4-to-1 fault-protected multiplexers that are pin compatible with the industry-standard DG508/DG509. The MAX4508/MAX4509 operate with dual supplies of ±4.5V to ±20V or a single supply of +9V to +36V. These multiplexers feature fault-protected inputs, rail-to-rail signal handling capability, and overvoltage clamping at 150mV beyond the rails.

Both parts offer ±40V overvoltage protection with supplies off and ±25V protection with supplies on. On-resistance is 400Ω max and is matched between channels to 15Ω max. All digital inputs have TTL logic thresholds, ensuring both TTL and CMOS logic compatibility when using a single +12V supply or dual ±15V supplies.

Applications

* Avionics * Data Acquisition Systems * Industrial and Process Control * Redundant/Backup Systems * Signal Routing

* ±40V Fault Protection with Power Off

±25V Fault Protection with ±15V Supplies

* Rail-to-Rail Signal Handling

* No Power-Supply Sequencing Required

* All Channels Off with Power Off

* Output Clamped to Appropriate Supply Voltage During Fault Condition

* 1kΩ Output Clamp Resistance During Overvoltage

* 400Ω max On-Resistance

* 20ns Fault-Response Time

* ±4.5V to ±20V Dual Supplies

+9V to +36V Single Supply

* TTL/CMOS-Compatible Logic Inputs