The Keithley 708A Semiconductor Switch Matrix Mainframe is a high-density signal routing platform for automated testing in semiconductor and telecommunications environments. This single-slot mainframe occupies just 3.5 inches of rack space and controls up to 96 channels of 2-pole switching. The 708A accepts DC and RF switch cards designed for the Model 707A, leveraging three separate analog backplanes that automatically establish row connections within card families—eliminating external wiring complexity. Front and rear panel card accessibility enables straightforward maintenance and reconfiguration.
## Technical Specifications
• **Channel Capacity:** Up to 96 channels (2-pole switching per card)
• **Expandability:** Daisy-chain configuration supports up to four slave units per master, enabling 480-channel systems
• **Rack Space:** 3.5 inches vertical in standard 19-inch rack
• **Matrix Storage:** 100 setups in non-volatile memory with lithium battery backup
• **Programmable Settling Time:** 0 to 65 seconds in 1 ms increments
• **Relay Drive:** 5 A capability
• **Maximum Trigger Rate:** 200 setups per second (make-before-break and break-before-make disabled)
• **IEEE-488 Response (Standalone):** <15 ms for single relay closure (excluding settling time)
• **IEEE-488 Response (Master + Four Slaves):** <55 ms
• **Setup Download Time:** Typically 50 ms
• **Power:** 100–240 V AC, 50–60 Hz, 110 VA maximum
## Key Features
• Relay status display on front panel
• Programmable make-before-break or break-before-make switching by row
• "Matrix Ready" TTL-compatible output indicating relay completion and settling time conclusion
• External trigger input (TTL compatible, programmable edge, 600 ns minimum pulse width)
• IEEE-488 bus control (TALK, GET, X commands)
• Manual trigger option
## Compatibility & Integration
The 708A accepts general-purpose and application-specific DC and RF switch cards originally developed for the Model 707A. Three integrated analog backplanes reduce integration effort by automatically creating row connections across compatible card families, streamlining test setup configuration.
