low noise current amplifier series LCA- Features

1. The lowest input noise is 180 aA/√Hz

2. Bandwidth up to 400 kHz

3. Gain up to10-13V/A

4. Flat frequency response

5. Compact size

In contrast to large desktop devices, compact preamplifier modules amplify signals directly at the source. This prevents SNR deterioration due to high cable capacitance or interference. Further signal processing after the first amplifier stage no longer affects the SNR, so longer cables can be used for compensation.

The input current noise of a commercial operational amplifier IC may be below 1 fA/√Hz. However, in practical circuits used as low frequency transimpedance amplifiers, I/U converters, the thermal noise of the feedback resistor Rf usually dominates. The lower this thermocurrent noise becomes, the higher the resistance Rf, and the higher the gain. Thus, FEMTO provides modules with magnification up to 10 13 V/A to achieve a minimum noise figure of 0.18 fA/√Hz.

For conventional wiring, as can often be found in the application instructions of the op-amp manufacturer, the bandwidth and measurement speed are usually significantly reduced at high gain values. Even with moderate amplification, a bandwidth of only a few Hertz is usually achieved, and modulation or time-resolved measurements are almost impossible. For this reason, FEMTO has developed special switching technologies over the years that, combined with specially selected components, provide very good results. Therefore, we can provide professional power amplifiers that truly deserve the "ultra-low noise" label. The noise performance far exceeds that of conventionally designed current-voltage converters with comparable bandwidth operational amplifiers. The LCA series is unbeatable, they are the lowest noise current-voltage converter modules currently on the market.

In addition to low noise, high bandwidth, and massive amplification, FEMTO current amplifiers exhibit near-ideal behavior in a variety of applications without any requirements for special adaptation or frequency compensation measures. The bandwidth and frequency response remain constant regardless of the connected source capacitance values up to 10 nF. No signal overshoot or gain variations due to source capacity variations occur.

Lock-in amplifiers usually have a special current input. The sensitivity and measurement speed of the DSP lock-in amplifier can even be significantly improved by using a low-noise current preamplifier module instead of the current input in noise-critical applications. The current in the Fan-ampere range is then measured in a few milliseconds.

Note: The bandwidth and frequency response are independent of the detector capacitance. Each amplifier is guaranteed and tested as low as 10nF. (LCA-400K-10M up to 1 nF).