Low-noise preamplifier selection guide
Current/Voltage converter for micro current amplification
- Supports a wide range of current signals between ultra-low currents less than fA and 1µA
- Combines high gain with wide frequency response
- Low noise on the order of sub-fA/√Hz (10-16)
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Information
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Measurement example
Information
Lineup
| Gain (V/A) | Frequency response | Equivalent input noise current density | |
|---|---|---|---|
| SA-604F2 | 10M | DC to 500kHz | 45fA/√Hz |
| SA-605F2 | 100M | DC to 250kHz | 15fA/√Hz |
| SA-606F2 | 1G | DC to 100kHz | 6fA/√Hz |
| SA-607F2 | 10G | DC to 20kHz | 2.5fA/√Hz |
| SA-608F2 | 100G | DC to 2kHz | 0.6fA/√Hz |
| SA-609F2 | 1T | DC to 300Hz | 0.4fA/√Hz |
Input voltage - Frequency response
The model line-up supports a wide current input range. Includes extremely ultra-low currents order of sub-pA.
Conversion gain - Frequency response
High gain and wide frequency response
*Survey conducted Dec 14, 2022
Output noise - Frequency response
Achieved the world's lowest noise characteristics
*Survey conducted Dec 14, 2022
Pulse response
Output waveform comparison at square wave small signal input
SA-604F2 (DC to 500kHz, 45fA/√Hz) [Input current: 100nAp-p]
SA-605F2 (DC to 250kHz, 15fA/√Hz) [Input current: 10nAp-p]
SA-606F2 (DC to 100kHz, 6fA/√Hz) [Input current: 1nAp-p]
SA-607F2 (DC to 20kHz, 2.5fA/√Hz) [Input current: 0.1nAp-p]
SA-608F2 (DC to 2kHz, 0.6fA/√Hz) [Input current: 10pAp-p]
SA-609F2 (DC to 300Hz, 0.4fA/√Hz) [Input current: 1pAp-p]
Built-in LPF set to THRU
Measurement example
Challenging the limits of signal detection (fA real-time signal)
Small signals amplified by the SA series are observed with an oscilloscope (bandwidth 1 MHz).
SA-609F2
- Input: 10fAp-p@0.3Hz
- Built-in LPF setting: 3Hz
- Input: 30fAp-p@30Hz
- Built-in LPF setting: THRU
Real-time detection of 10fAp-p and 30fAp-p micro signals
Challenging signal detection limits (fA repetitive signal)
Connect multiple SA series units and observe using the averaging function of the oscilloscope.
Measurement example
SA-609F2
- Input: 1fAp-p@0.5Hz,
Pulse width: 500ms - LPF setting: 3Hz
- Averaging process: 1,000 times
SA-607F2
- Input: 10fAp-p@55Hz,
Pulse width: 3.64ms - LPF setting: 1kHz
- Averaging process: 10,000 times
Successfully detected 1fAp-p and 10fAp-p signals
Performance comparison with competitors
Pulse waveform responses
NF's amplifiers are capable of capturing signal changes at higher speeds.
- Input current: ±1nA
- Gain: 10G (V/A)
| Input signal frequency | 100Hz (x-axis: 2ms/div) |
1kHz (x-axis: 200µs/div) |
10kHz (x-axis: 20µs/div) |
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SA-607F2 |
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Current Amplifier A |
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Current Amplifier C |
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*Survey conducted June 16, 2017
SA-609F2
- Input current: ±10pA
- Gain: 1T (V/A)
| Input signal frequency | 1Hz |
10Hz |
100Hz |
|---|---|---|---|
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SA-609F2 |
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Current Amplifier A |
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*Survey conducted Dec 14, 2022