Keithley 487 Picoammeter/Voltage Source

The Keithley 487 Picoammeter/Voltage Source combines precision current measurement with stable DC voltage sourcing in a single instrument. It measures currents from 10 fA to 2 mA with resolution as fine as 0.01 fA, and calculates resistance across 500 mΩ to 5 × 10¹⁶ Ω. The integrated ±500 V programmable voltage source delivers output accuracy of ±(0.15% + 40 mV) on the high range and ±(0.1% + 4 mV) on the 50 V range, with selectable current limits of 2.5 mA or 25 µA. Dual displays enable simultaneous monitoring of voltage settings and measured current.

– Technical Specifications

Current Measurement
• Range: 10 fA to 2 mA
• Resolution: 0.01 fA to 10 fA (range-dependent)
• Accuracy: ±(0.02% + 10 fA) on sensitive ranges; ±(0.1% to 0.3%) + offset on microamp ranges
• Input voltage burden: <200 µV (18–28°C) for inputs <100 µA; 60 dB at 50/60 Hz
• Autoranging time: <200 ms to final range
• Maximum reading rates: 180 readings/second (continuous triggered); 100 readings/second (41/2-digit, IEEE-488); 40 readings/second (51/2-digit, IEEE-488)
• Data storage: Up to 512 readings

Voltage Source
• Output range: ±500 V DC
• Resolution: 10 mV (500 V range); 1 mV (50 V range)
• Accuracy: ±(0.15% + 40 mV) on ±505 V range; ±(0.1% + 4 mV) on ±50.5 V range
• Output noise: <1.5 mV p-p (±505 V); <150 µV p-p (±50.5 V)
• Output resistance: <2.5 Ω
• Time stability: ±(0.003% + 1 mV) over 24 hours

– Key Features

• Selectable analog filters for wideband or low-noise operation
• PRESET button allows toggling between two separate source values
• Automatic or manual ranging
• Temperature coefficient: ±(0.15 × applicable accuracy)/°C outside 18–28°C range

– Typical Applications

Device characterization, material analysis, high-impedance measurements, leakage current testing.

– Compatibility & Integration

IEEE-488 bus interface for remote operation and data acquisition.