Adjustable Offset and Bias

The highly flexible FEMTO’S HCA current amplifier provides precise offset and bias adjustments through two trim pots. The adjustable input offset current component can even preserve the full dynamic range of signals with large DC components. The bias output voltage can be precisely adjusted from -12 to +12 V using the multi-turn bias trim pot.

Features of the HCA Series High-Speed Current Amplifiers:

* Low input noise 270 fA/√Hz

Bandwidth up to 400 MHz

Gain up to 10? V/A

Smooth frequency response

Stable and adjustable bias voltage output for additional photodiodes

EMI isolation

High Frequency — Designed for Experts?

Users of high-frequency components often face issues such as unwanted oscillations, poor ground shielding, nonlinear gain increase, and bandwidth reduction due to outdated amplifier design. FEMTO high-frequency amplifiers are designed to eliminate these undesirable problems. FEMTO high-frequency amplifiers feature source-insensitive parameters and input wiring that are carefully implemented within their specifications. There will be no gain peaking, oscillations, or significant bandwidth reduction, even with source capacitances up to 2 nF (for HCA-1M-1M-C).

Bandwidth Independent of Source Capacitance

Only a small source capacitance in the picofarad range can drastically reduce the bandwidth of high-frequency current amplifiers. However, FEMTO current amplifiers are not subject to these limitations and remain unaffected over a wide range of source capacitances. Without the need for frequency compensation or specific adjustments, the bandwidth and gain remain constant for the maximum source capacitance specified for each amplifier model.

"C"-MODELS (C Models)

Amplifier models are also available in a "C" version, which is designed for very large source capacitances up to nanofarads. They are highly effective for measuring fast signals, such as those from planar detectors with capacitances in the nanofarad range. For detectors with capacitances exceeding 2 nF, custom designs are available. For more details, please contact us.

Applications:

Fast detection with large-area photodiodes

Spectroscopy

PMT and photodiode detection

Ionization detectors

Pyroelectric and piezoelectric detectors

Output voltage ±1.5 V, @50 Ω load, offset adjustable via trim pot. Optional AC coupling. Output short-circuit protected. Bias output adjustable for photodetector bias (-12...+12 V). Power supply via 3-pin Lemo socket, matching connector provided. PS-15 power supply unit available.