Keithley 7707 Multiplexer Digital Module

The Keithley 7707 Multiplexer Digital Module is a plug-in expansion card for Keithley Models 2700, 2701, and 2750 data acquisition systems. It combines 10 channels of differential multiplexer switching with 32 channels of digital I/O to enable complex automated test sequences, signal routing, and external device control. The module supports flexible channel configurations—10 channels in 2-pole mode or 5 channels in 4-pole mode—and can operate as two independent multiplexer banks for parallel measurement paths.

– Technical Specifications

Multiplexer Channels
• Configuration: 10 × 2-pole or 5 × 4-pole
• Maximum signal level: 300 VDC, 300 Vrms (425 V peak AC), 1 A switched, 60 W / 125 VA
• Contact resistance: < 1 Ω any path; 10⁵ operations at maximum signal; > 10⁸ no-load operations
• Contact potential: < 6 µV typical per pair
• Offset current: < 100 pA
• Insertion loss: < 0.1 dB below 1 MHz; < 3 dB below 2 MHz (50 Ω system)
• Crosstalk (10 MHz, 50 Ω load): 10⁹ Ω, 10⁹ Ω, < 100 pF
• Common-mode voltage: 300 VDC, 300 Vrms (425 V peak AC)
• Minimum signal level: 10 mV, 10 µA
• Actuation time: < 3 ms
• Relay type: Latching electromechanical

Digital I/O Channels
• Count: 32 channels (four 8-bit ports)
• Capacity: 33 V, 100 mA per output
• Digital input thresholds: VIN(L) 2 V
• Digital output levels: VOUT(L) 2.4 V @ 1 mA
• Thermal protection: Channels 11–14 protected to 1 A up to 25 V
• Short-circuit protection on all outputs

– Key Features

• Flexible multiplexer topology for differential measurements and switching control
• Low contact resistance and minimal contact potential for precision applications
• High isolation exceeding 10⁹ Ω ensures signal integrity across channels
• TTL-compatible digital I/O with short-circuit and thermal protection
• Latching relays reduce power consumption in idle states

– Typical Applications

• Multi-channel signal acquisition and automated measurement routing
• Digital control of external instrumentation and switching matrices
• Temperature, voltage, and resistance measurements across distributed test points
• Parallel test sequences using independent multiplexer banks

– Compatibility & Integration

The 7707 module integrates directly with Keithley 2700, 2701, and 2750 mainframes via standard plug-in architecture, inheriting host system measurement accuracy and control functionality.