Keithley 485 Autoranging Picoammeter, 4.5 Digits

Keithley 485 Autoranging Picoammeter

The Keithley 485 Autoranging Picoammeter is a low-cost yet highly sensitive solution designed for a wide range of applications in testing, research, and educational laboratories. This easy-to-use instrument boasts the ability to withstand extremely high overloads, ensuring reliability across various testing scenarios. Featuring an analog output that linearly converts incoming current to voltage, the Keithley 485 is ideal for hard copy outputs or control loop applications.

With advanced feedback techniques, the Keithley 485 actively constrains input voltage drop, allowing for high accuracy current measurements even in circuits with very low source voltages. The picoammeter is equipped with several key features that simplify low current measurements:

• Autorange Mode: Maximizes resolution for precise measurements.
• REL Button: Facilitates relative readings against a baseline.
• LOG Button: Displays logarithm (base 10) of the measured current for easier analysis.
• Digital Calibration: Conducted easily from the front panel or via the bus.
• Data Store Buffer: A 100-point storage solution capable of automatic readings at six selectable rates, ranging from three readings per second to one per hour.

Key Features and Specifications:

• Sensitivity: 100fA
• Low Voltage Burden:
  • Ensures greater measurement accuracy.
  • Makes the 485 approach an ideal ammeter.
• Log I Readings: For comprehensive data analysis.
• Optional IEEE-488 Interface: Enhances connectivity and control capabilities.
• Optional Rechargeable Battery Pack:
  • Enables battery operation for mobility.
  • Provides isolation from power lines.
• Input Voltage Burden: Less than 200µV
• Ranging: Choose between manual or autoranging depending on your requirements.
• Autoranging Time: Average 250 ms per range change.
• Settling Time at Display: Conversion Period: 300ms
• Temperature Coefficient: ±(0.1 × applicable accuracy specification)/°C (0°C–18°C & 28°C–50°C)
• Maximum Common Mode Voltage: 30V rms, DC to 60Hz sine wave
• Analog Output:
  • Output Voltage: +1V = -10000 counts (except +100mV = -10000 counts on 2nA range)
  • Output Resistance: 1kΩ
• REL Functionality:
  • Zero out on-range readings for accurate comparisons.
  • Facilitates relative readings based on a baseline.
  • Front panel indicator signals when REL mode is active.
• Data Store and Min/Max:
  • Accumulates 100 readings with a continuous update of max/min values.
  • Records at one of six selectable rates or manually.
• Log Function:
  • Displays logarithm (base 10) of the absolute value of measured current.
  • Examples: -3.000 = ±1mA; -6.301 = ±0.5μA