Photodiode Amplifier

This amplifier unit is a low noise, high gain, transimpedance amplifier that is designed to provide a direct digital readout of the current generated from a photodiode, photomultiplier, or similar current source. If a reading in Watts is desired, simply toggle the A/W setting. By adjusting the A/W setting on the amplifier to equal detector responsivity, the amplifier can measure the incident optical power. For detectors that require a reverse bias, the unit can apply a selectable bias in series with the photodetector.

An output voltage port provides a ±2V full-scale analog signal directly proportional to the LCD display reading. For noise-sensitive measurements, the unit can be disconnected from its external supply and powered from its internal batteries. Battery low indicator is activated on the LCD when batteries need recharging via included power supply. Universal power supply includes wall connectors for US, UK, Europe and Australia.

• Max Input without Damage: ±25mA
• Full Scale Ranges: ±20nA to 20mA in Decade Steps
• A/W Setting: 0.100 - 1.0000 in 0.005 Increments, Default = 1 When not Engaged
• Bias Voltage: Selectable -14V to +14V in 7mV Increments, Default = 1 When not Engaged
• Offset Control: Offsets Display by up to ±20,000 Counts
• Noise: <1pA p-p, DC - 1kHz with <10pF Detector Capacitance
• Frequency Response (-3dB): 20nA from DC to 2.0kHz, 100nA from DC to 5.25kHz, 2μA from DC to 22kHz, 20μA, 200μA, 2mA, 20mA from DC to 40kHz
• Display: 4 1/2 Digit, 0.4" High LCD