Keithley 7710 20 Channel Solid State/Long Life Differential Multiplexer Card with Auto CJC

The Keithley 7710 is a 20-channel solid-state differential multiplexer card built for high-speed, high-reliability switching in data acquisition systems. It configures as 20 channels of 2-pole relay input or up to 10 channels of 4-pole operation, organized into two independent multiplexer banks. Opto-coupled FET relays deliver switching actuation in less than 0.5 ms and enable scanning at up to 500 channels/second. Solid-state design eliminates mechanical relay wear, extending operational life beyond 10⁵ hours at full signal level or 10¹⁰ operations by design specification. Built-in automatic cold junction compensation (CJC) streamlines thermocouple measurements to within 1°C accuracy for K-type devices.

– Technical Specifications

Switching Performance
• Maximum signal: 60 VDC or 42 Vrms, 100 mA switched, 6 W, 4.2 VA
• Common mode voltage: 300 VDC or 300 Vrms (425 V peak) maximum to chassis
• Channel resistance: Less than 5 Ω per conductor
• Contact potential: Less than 1 µV per pair
• Offset current: Less than 3 nA @ 23°C, +0.13 nA/°C above 23°C
• Isolation (channel-to-channel): Greater than 10⁹ Ω, less than 100 pF
• Isolation (channel-to-earth): Greater than 10⁹ Ω, less than 100 pF
• Crosstalk (300 kHz, 50 Ω load): Less than –40 dB
• Insertion loss: Less than 0.5 dB below 100 kHz; less than 3 dB below 2 MHz
• Relay drive current: 6 mA continuous, 25 mA initial pulse

Temperature
• Operating: 0°C to 50°C at 80% RH @ 35°C
• Storage: –25°C to 65°C

– Key Features

• Opto-coupled FET relay technology for long-term reliability
• Configurable 2-pole and 4-pole channel modes
• Dual independent multiplexer banks
• Automatic CJC for thermocouple applications
• Sub-0.5 ms switching with 100 mA load
• 500 channels/second scanning speed
• 3.5 mm screw terminals, #20 AWG compatible

– Typical Applications

• Thermocouple and RTD data logging
• High-speed multi-channel switching
• Low-level analog signal multiplexing
• Long-duration automated test systems
• Resistance and 4-wire measurements

– Compatibility & Integration

Designed for Keithley Model 2700 (Rev. B05 firmware or later) and Model 2701 mainframes.