Keithley 7705 40 Channel Control Module

The Keithley 7705 is a 40-channel control module that delivers single-pole switching capability for test automation without measurement functions. Built around latching electromechanical relays, It has independent Form A switches to control power distribution to devices under test, external indicators, and relay networks. Relay states are retained in onboard memory across power interruptions - until a power cycle or reset command returns all channels to open.

The module connects to Keithley mainframes through dual 50-pin female D-sub connectors and operates at signal levels up to 300 V DC/RMS and 2 A, handling up to 60 W DC or 125 VA AC (resistive loads). Channel resistance measures below 1 ohm with contact potential under ±4 µV and offset current below 100 pA, delivering the low-noise switching required for precision test setups. Actuation occurs in 3 ms, enabling fast relay transitions in high-volume test sequences.

Technical Specifications

• Channels: 40 independent Form A switches (SPST)


• Relay Type: Latching electromechanical with onboard state memory


• Maximum Signal Level: 300 V DC or RMS, 2 A switched


• Maximum Power: 60 W (DC, resistive); 125 VA (AC, resistive)


• Channel Resistance: <1 Ω per conductor


• Contact Potential: <±4 µV per contact


• Offset Current: <100 pA


• Actuation Time: 3 ms


• Connector: Two 50-pin female D-sub connectors


• Weight: ~0.45 kg (1 lb)


• Operating Range: 0°C to 50°C, 0–80% RH (at 35°C)


• Storage Range: –25°C to 65°C

Key Features

• Non-measurement switching module; channels isolated from DMM backplane


• Latching relays retain state without power; reset to open on power cycle


• Low contact potential and offset current minimize signal distortion


• Quick 3 ms relay actuation for fast test cycles


• Two mating 50-pin connectors (Model 7788) typically included

Typical Applications

• Power distribution control in multi-device test benches


• External relay and indicator automation


• Load switching in DC and AC power test systems


• Test matrix expansion for 7700 series mainframes

Compatibility & Integration The 7705 integrates with Keithley 2700 Series mainframes (2700, 2701, 2750) and the DAQ6510 Data Acquisition and Multimeter System.