ADI ADA4530-1ARZ

The ADA4530-1 is an fA-level (10⁻¹⁵A) input bias current op-amp designed for use as an electrometer, with an integrated guard ring buffer. It operates from 4.5 V to 16 V, supporting standard 5 V and 10 V single-supply as well as ±2.5 V and ±5 V dual-supply systems.

The device offers ultralow input bias current, with production testing of input bias current at both 25°C and 125°C to ensure the device meets user system performance targets. The integrated guard ring buffer isolates the input pins from PCB leakage currents, reduces board component count, and simplifies system design. The ADA4530-1 is housed in an industry-standard 8-lead SOIC SMT package with a unique pin configuration optimized to prevent signal coupling between sensitive input pins, supply pins, and output pins, while simplifying guard ring trace routing.

The ADA4530-1 also features low offset voltage, low offset drift, low voltage noise, and low current noise, making it suitable for applications requiring extremely low leakage current.

To maximize system dynamic range, the ADA4530-1 incorporates a rail-to-rail output stage capable of swinging to within 30 mV of either supply rail under a 10 kΩ load (typical).

The ADA4530-1 operates over the -40°C to +125°C industrial temperature range and is available in an 8-lead SOIC package.

• Low input bias current: ±20 fA (max, TA = 25°C, guaranteed by production test); ±20 fA (max, -40°C < TA < +85°C); ±250 fA (max, -40°C < TA < +125°C, guaranteed by production test)
• Low offset voltage: 50 μV (max, over rated CMRR range)
• Offset voltage drift: ±0.13 μV/°C (typ), ±0.5 μV/°C (max)
• Integrated guard ring buffer with 100 μV max offset
• Low voltage noise density: 14 nV/√Hz (10 kHz)
• Wide bandwidth: 2 MHz
• Unity-gain crossover
• Supply voltage: 4.5 V to 16 V (±2.25 V to ±8 V)
• Operating temperature: -40°C to +125°C
• Long-term offset voltage drift (10,000 hours): 0.5 μV (typ)
• Temperature hysteresis: 1.5 μV (typ)

• Laboratory and analytical instrumentation: spectrophotometers, chromatographs, mass spectrometers, potentiostatic and galvanostatic coulometric analysis
• Instrumentation: picoammeters, coulometers
• Transimpedance amplifier (TIA) for photodiode, ionization chamber, and working electrode measurements
• High-impedance buffer for chemical sensors and capacitive sensors