Keithley 7706 All-in-One I/O Module

The Keithley 7706 All-in-One I/O Module is a plug-in module for Keithley data acquisition systems that combines multiplexed analog inputs, analog outputs, digital I/O, counter/totalizer, and latching relay switching in a single unit. It handles signal routing and control across temperature measurement, discrete switching, and event monitoring applications without requiring multiple external interfaces.

– Technical Specifications

Analog Input/Multiplexer
• 20 channels configurable as 2-pole or 10 channels of 4-pole multiplexer switching
• Maximum signal level: 300V DC or RMS, 1A switched
• Maximum power handling: 60W, 125VA
• Integrated automatic cold junction compensation (CJC) for RTD, thermistor, and thermocouple measurements
• Two independent multiplexer banks supported

Analog Output
• 2 channels, ±12V range, 5mA maximum output current
• 1mV resolution with 1ms settling time to 0.01%
• Accuracy: 0.04% + 19mV (24 hour, ±1°C); 0.1% + 19mV (90 day, ±5°C); 0.15% + 19mV (1 year, ±5°C)
• Temperature coefficient: ±(0.015% + 1mV)/°C
• Non-isolated output

Digital I/O
• 16 digital output channels
• Output voltage low: 2.4V @ 1mA
• Maximum voltage high with external open drain pull-up: <42V
• Write speed: 50/s

Counter/Totalizer
• One event counter channel, maximum count 2³² – 1
• Input frequency to 100kHz (max), rising or falling edge selectable
• Signal level range: 1Vp-p minimum, 42Vpk maximum
• Threshold: 0V or TTL, jumper selectable; gate input TTL-Hi, TTL-Lo, or none
• Read speed: 50/s; count reset manual or Read+Reset

Relay Switching
• Latching electromechanical relays with 10⁵ operations at maximum signal level; >10⁸ operations no load
• Contact resistance: <1Ω at end of contact life
• Contact potential: <±2µV typical, 6µV maximum; offset current 10⁹ Ω, 10⁹ Ω, <200pF
• Cross talk at 10MHz with 50Ω load: <–35dB

– Key Features

• Flexible channel configuration for mixed-signal applications
• Low contact resistance and offset current for precision signal switching
• TTL/0V threshold selectivity for counter inputs
• High isolation ratings across all signal paths

– Typical Applications

• Temperature measurement systems using thermocouples, RTDs, and thermistors
• Fixture control and limit switch monitoring
• Pass/fail indication and external load management
• Revolution counting and event monitoring
• Multi-channel signal routing in automated test systems

– Compatibility & Integration

Designed as a plug-in module for Keithley data acquisition systems. Latching relay architecture minimizes power consumption during idle states, suitable for extended continuous operation in laboratory and enterprise environments.