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home > Products > Measurement Instruments > Lock-in Amplifier/Preamplifier > Preamplifier > SA-200 Series
Selection Guide

Small signal measurement instruments

Low Noise Amplifier
SA-200 series

World's top level single-ended amplifier with extremely low noise

  • Wide voltage range measurement
    (sub micro-Volt to milli-Volt)
  • Wide frequency range measurement
    (DC to 100MHz)
  • Covering the various signal source impedance
SA-200F3


Signal from sensors Low frequency signal High frequency signal
Low impedance SA-200F3
DC to 800 kHz, Output 20 Vp-p
SA-230F5
1 kHz to 100 MHz, Output 1.8 Vp-p
High impedance SA-240F5
DC to 20 MHz, Output 20 Vp-p
SA-220F5
1 kHz to 80 MHz, Output 2 Vp-p


Input voltage against frequency

SA-200 series:

Amplifies extremely small voltage such as sub micro-Volt.

 Cut-off frequency

World's top level amplifier with extremely low noise

The SA-200 series amplifies low and high frequency signals with low noise.

Equivalent input noise voltage density against Cut-off frequency

SA-200 series:

World's top level amplifier with low noise and wideband frequency (DC to 100 MHz).

 Cut-off frequency
*Novemver 22,2018

The SA-200 series covers various voltage-output sensors.

Both low input impedance models and high input impedance models realize extremely low noise.

Equivalent input noise voltage density against input impedance

SA-200 series:

Covers various signal source impedance.

Input impedance
*Novemver 22,2018
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Pulse response

Output waveforms ( Input: 100μVp-p square wave)

* Upper waveform: without LPF
   Lower waveform: with LPF (fc = 1 MHz)

SA-200F3

100Hz 1kHz 10kHz
SA製品画像 Zin=1k/ 10k/ 100kΩ, G=40dB,
DC to 800kHz, 0.5nV/√Hz
100Hz 1kHz 10kHz
100kHz 1MHz 10MHz
100kHz 1MHz 10MHz

SA-220F5

100Hz 1kHz 10kHz
SA製品画像 Zin=1MΩ, G=46dB,
1kHz to 80MHz,
0.5nV/√Hz
100Hz 1kHz 10kHz
100kHz 1MHz 10MHz
100kHz 1MHz 10MHz

SA-230F5

100Hz 1kHz 10kHz
SA製品画像 Zin=50Ω,  G=46dB,
1kHz to 100MHz,
0.25nV/√Hz
100Hz 1kHz 10kHz
100kHz 1MHz 10MHz
100kHz 1MHz 10MHz

SA-240F5

100Hz 1kHz 10kHz
SA製品画像 Zin=1MΩ, 100MΩ,
OPEN, G=40dB,
DC to 20MHz,
1.2nV/√Hz
100Hz 1kHz 10kHz
100kHz 1MHz 10MHz
100kHz 1MHz 10MHz


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Application example: Power supply noise measurement

Measurement of our DC power supply LP5394 output noise using a signal analyzer

Without preamplifier
(Signal analyzer only)
[Measurement result]

signal analyzer
7.6nV/√Hz@200kHz
Without preamplifier
Power supply noise is unmeasurable due to the large
noise of the signal analyzer.

With a preamplifier "SA-220F5" [Measurement result]

Signal analyzer
Signal analyzer

and

SA-220F5
SA-220F5
0.5nV/√Hz@200kHz
With SA-220F5
Successful in detecting power supply noise up to 30kHz.
  *Detection sensitivity improved around 10 times

With a preamplifier "SA-230F5" [Measurement result]

Signal analyzer
Signal analyzer

and

SA-230F5
SA-230F5
0.25nV/√Hz@200kHz
With SA-230F5
Successful in detecting power supply noise up to 40kHz
  *Detection sensitivity improved around 20 times

If you use our low noise amplifiers:
You can obtain extreamly small signals which you could not before.
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Challenge to the small signal measurement
- Micro-Volt real-time signal measurement -

Displays amplified sine wave signals on oscilloscope(BW: 1 MHz) by the SA-200F3 (1-stage, 40dB gain).

      Successful in 5μVp-p real-time signal measurement

Measurement condition: using the LPF whose cut-off frequency is approximately 5 times higher than the signal frequency.

55Hz,LPF=300Hz

Input: 55Hz
LPF=300Hz

550Hz LPF=3kHz

Input: 550Hz
LPF=3kHz

5.5kHz LPF=30kHz

Input: 5.5kHz
LPF=30kHz

55kHz LPF=300kHz

Input: 55kHz
LPF=300kHz

  Without LPF

55Hz

Input: 55Hz

550Hz

Input: 550Hz

5.5kHz

Input: 5.5kHz

55kHz

Input: 55kHz


Displays amplified pulse wave signals on oscilloscope by the SA-200F3 (1-stages, 40 dB gain).

    Successful in 5μVp-p real-time signal measurement

Measurement condition: using the LPF whose cut-off frequency is approximately 5 times higher than the signal frequency.

55Hz

Input: 55Hz
LPF=300Hz

550Hz

Input: 550Hz
LPF=3kHz

5.5kHz

Input: 5.5kHz
LPF=30kHz

55kHz

Input: 55kHz
LPF=300kHz

  Without LPF

55Hz

Input: 55Hz

550Hz

Input: 550Hz

5.5kHz

Input: 5.5kHz

55kHz

Input: 55kHz


Challenge to the small signal measurement
- Repeated nano-Volt signal detection -

Displays amplified pulse wave signals on oscilloscope by SA-200F3 as a first stage amplifier. (Total gain 120dB)

  Number of averaging by digital oscilloscope: 512

    Successful in 40 nVp-p repeated signal detection

Input: 40nVp-p pulse wave 55Hz,
LPF: 1kHz
Input: 40nVp-p pulse wave 550Hz,
LPF: 10kHz
40nV, 55Hz 40nV, 550Hz

  Number of averaging by digital oscilloscope: 10000

    Successful in 4nVp-p repeated signal measurement

Input: 4nVp-p pulse wave 55Hz,
LPF: 1kHz
Input: 8nVp-p pulse wave 55Hz,
LPF: 1kHz
4nV, 55Hz 40nV, 550Hz

  Measurement block diagram

測定系イメージ
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Product customization is available upon requests.

Points of Customization:

Modify the Voltage Gain
Reduced Overload Recovery Time
Frequency Characteristics (Cutoff frequency modification in low/high frequency range)
Multi-channel

 

Amplifiers for MRI/NMR

Reduced overload recovery time

Low noise amplifiers for MRI/NMR need to measure immediately after large input signals changed to very small signals.
Therefore, reducing the overload recovery time for an amplifier from being saturated back to normal is important.



Customization Example of SA-220F5

The overload recovery time has reduced from 10ms to 10µs after customization on SA-220F5.


sa-230f5
Specifications after customization (Example)

Equivalent Input Noise Voltage Density: 0.5nV/√Hz@2MHz
Overload Recovery Time: 10µs
Frequency characteristics of Voltage Gain: 300k to 80MHz
sa-230f5
【Frequency Characteristics of Voltage Gain after customization】
 


Customization Example of SA-230F5

The overload recovery time has reduced from 120ms to 8µs after customization on SA-230F5.
Moreover, the cutoff frequency is customized up to 250MHz (or higher) from the original 100MHz upon a customer request for higher speed.


sa-230f5
Specifications after customization (Example)

Noise Figure: 0.6 dB@40MHz
Overload Recovery Time: 8µs
Voltage Gain: 40dB (RL=50Ω)
Frequency Characteristics of Voltage Gain: 1M to 250MHz
sa-230f5
【Frequency Characteristics of Voltage Gain after Customization】
 
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Bandwidth Customization

Bandwidth extension

The bandwidth can be spread by lowering the gain.

Customization Example List

Input Type Model Standard Frequency Characteristics Frequency Characteristics after gain modified
Single-ended Input SA-220F5 1k to 80MHz (Gain 46dB) 1k to 130MHz (Gain 40dB)
SA-230F5 1k to 100MHz (Gain 46dB) 1k to 200MHz (Gain 40dB)
SA-240F5 DC to 20MHz (Gain 40dB) DC to 40MHz (Gain 40dB)

*The bandwidth of SA-240F5 can be extended without the gain modification.
Differential Input SA-420F5 1k to 70MHz (Gain 46dB) 1k to 110MHz (Gain 40dB)


Customization Example of SA-230F5

By modifying the gain from 46dB to 40dB, a wider bandwidth of 1kHz to 200MHz is achieved.
And this customization does not affect the noise performance (noise figure) of the amplifier.

SA-230F5カスタム実績
【Frequency Characteristics of Voltage Gain (Normalized to 1MHz )】
SA-230F5カスタム実績
【Noise Figure】
 
SA-230F5カスタム実績
【Output Waveforms (gain from 46dB to 40dB)】

 



Gain customization

The gain can be increased by narrowing the bandwidth.

Customization Example of SA-200F3

By modifying the bandwidth (maximum frequency) from 800kHz to 700kHz, a gain-up of 40dB to 52dB is achieved.

And this customization does not affect the noise performance of the amplifier.

By matching the gain with SA-230F5, it is possible to cover the bandwidth from DC to 100MHz using SA-230F5 and customized SA-200F3.
*The gain is equivalent to 46dB when the load is 50Ω.

 

 

Related keywords :  Ultra low noise amplifier, LNA
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