The Keithley 224 Current Source is a precision DC current generator engineered for bench and system integration in component testing, sensor calibration, and material research. It delivers programmable current output with selectable voltage compliance, responsive transient behavior, and optional IEEE-488 remote control for automated test sequences.
Technical Specifications
Current Output
• Range: ±5 nA to ±101 mA DC
• Minimum step: 5 nA
• Output resistance: >10¹² Ω (10 µA range)
• Output capacitance: <20 pF
Voltage Compliance (V-LIMIT)
• Programmable range: ±1 V to ±105 V in 1 V steps
• V-LIMIT indication: LED with SRQ capability when IEEE-488 option installed
Transient Performance
• Response time: <3 ms to within 0.1% of programmed change
• Recovery time: <3 ms to rated accuracy following compliance voltage change
Increment/Decrement Control
• Modes: Manual, automatic, or trigger-based
• Dwell time range: 50 ms to 999.9 s per step
• Dwell accuracy: ±(0.05% + 20 µs)
• Minimum step size: 0.1% of selected range
• HI-LO limits available for automatic sweep control
Guard Output
• Output accuracy: ±1 mV (excluding lead drop)
• Maximum load capacitance: 10 nF
• Combined output + guard current: ≤105 mA absolute
Regulation
• Line regulation: <0.01% (within specified AC limits)
• Load regulation (V/C): 0.1%
Power
• Input: 105–125 V AC or 210–250 V AC (user-selectable), 50/60 Hz
• Consumption: 60 W maximum (80 VA maximum)
• Common mode voltage rating: 250 V rms DC to 60 Hz
– Key Features
• Non-inductive load requirement ensures stable operation
• Guard output maintains output voltage accuracy independent of cable resistance
• Programmable step size and dwell timing for automated ramp sequences
• IEEE-488 option (2243) enables remote current/compliance control and service request masking
– Typical Applications
Component characterization, precision sensor excitation, leakage current measurement, device reliability testing, and parametric sweep automation in laboratory and production environments.
– Compatibility & Integration
Optional IEEE-488 interface supports full remote programming of current, voltage limits, and digital I/O (4 TTL input and 4 TTL output lines). Field installable without factory service.
