The Keithley 616 Analog Range Digital Electrometer is a precision instrument engineered for accurate measurement of extremely low currents, high resistances, and electrical charges across voltage, current, resistance, and charge domains. The design integrates analog auto-ranging with digital display to deliver stable, repeatable readings essential in research, development, and quality control environments. This electrometer optimizes high source impedance applications while maintaining exceptional input isolation and common mode rejection.
Technical Specifications
Voltage Measurement
• Ranges: ±10 mV to ±100 V in decade steps with auto-ranging and 100% overranging to 1999
• Sensitivity: 10 µV/digit
• Accuracy: 0.2%
• Input impedance: >2 × 10¹⁴ Ω shunted by 20 pF; selectable decade steps from 10 Ω to 10⁴¹ Ω
• Reading time: <4 s to within 0.1% of final reading
• Zero drift: <(50 µV + 0.01% of range)/°C; <100 µV per 24 hours after warm-up
• Noise: 10 µV input-shorted
Current Measurement
• Ranges: ±10⁻¹³ A to ±100 mA in 13 decade ranges
• Accuracy: ±(0.5% reading + 0.1% range) for 10⁻¹ to 10⁻⁷ A; ±(2% reading + 0.1% range) for 10⁻⁸ A; ±(5% reading + 0.1% range) for 10⁻⁹ to 10⁻¹¹ A
• Offset current: 140 dB at line frequency with up to 10¹¹ Ω source resistance
• Circuit Lo to chassis ground isolation: >10⁹ Ω shunted by 500 pF
• Floating capability: Circuit Lo to ±1000 V with respect to chassis ground
Power
• Requirements: 90–125 VAC or 180–250 VAC (switch-selected), 50–60 Hz, 9 W
– Key Features
• Triaxial input connector with Teflon insulation
• Box-within-a-box construction maintains <0.1 pF unshielded capacitance from input HI to chassis ground
• Decade-selectable input resistance for flexibility
– Typical Applications
Research environments requiring picoampere-level current detection, high-impedance source characterization, electrostatic charge assessment, and precision voltage measurement in sensitive electronic systems.
