The Keithley 7111-S is a low-voltage, quad 1×10 single-pole Form C multiplexer card for the 7001 and 7002 switch mainframes. It combines a screw terminal connector card and relay card into a single assembly, enabling direct wiring of external test circuits while delivering the low contact potential and minimal offset current required for sensitive measurements. Four independent multiplexer banks can be interconnected or isolated via jumpers, and the card reconfigures as two independent 1×10 two-pole banks when needed.
## Technical Specifications
• **Multiplex Configuration:** Four independent 1×10 single-pole Form C banks; configurable as two 1×10 two-pole banks
• **Connector Type:** Screw terminals; accepts #16 AWG (0.092 inch O.D.) for up to 28 conductors per card, or #22 AWG (0.062 inch O.D.) for up to 88 conductors per card
• **Signal Levels:** 110 V DC, 1 A switched, 30 VA (resistive); 125 V RMS and 175 V AC peak, 1 A switched, 60 VA (resistive)
• **Common Mode Voltage:** 175 V peak, any pin to chassis
• **Contact Life:** 10⁸ closures cold switching; 10⁵ closures at maximum signal levels
• **Channel Resistance:** Less than 1 Ω per conductor
• **Contact Potential:** Less than 500 nV per channel contact pair; less than 3 µV typical per single contact
• **Offset Current:** Less than 100 pA
• **Actuation Time:** 3 ms
• **Isolation (Bank):** Greater than 10⁹ Ω, less than 25 pF
• **Isolation (Channel to Channel):** Greater than 10⁹ Ω, less than 50 pF
• **Crosstalk (1 MHz, 50 Ω load):** Less than –40 dB
• **Insertion Loss:** Less than 0.1 dB below 1 MHz; less than 3 dB below 2 MHz (50 Ω source and load)
• **Relay Drive Current:** 16 mA per relay
## Key Features
• Screw terminal design permits direct external wiring without adapters
• Adjacent banks interconnect for expanded multiplexing configurations
• Jumper-selectable bank isolation from backplane
• Contact potential below 500 nV supports precision analog switching
• Form C architecture enables simultaneous make-before-break transitions
## Compatibility & Integration
The 7111-S integrates directly with Keithley 7001 and 7002 mainframes via removable jumper connections to the analog backplane. Two cards cascade into a single 1×80 multiplexer through intercard backplane paths.
