Posted 2020/5/20
Measuring a small AC signal superimposed on a large DC signal requires a preamplifier that could not only remove DC voltage but also maintain low noise. The preamplifier "CMP61102" is a product that satisfies both of these requirements. (Figure 2.) The protection circuit that can input a DC signal of 40V or 80V protects the amplifier from damage caused by large voltage. Electrical Characteristics are shown in Table 2.
Figure 2. Preamplifier for measuring small AC signals superimposed on large DC signals
Table 2. Electrical Characteristics
| Description | Electrical Characteristics |
|---|---|
| Maximum Input Voltage | ±40 V *Extension to ±80 V is possible |
| Input Impedance | 100 kΩ |
| Voltage Gain | 60 dB |
| Equivalent Input Noise Voltage Density | 2 nV/√Hz or less |
| Upper Cutoff Frequency | 3 MHz |
| LPF Switching Function (Upper cutoff frequency setting values) |
7 levels switchable via a rotary switch 10, 100, 1k, 10k, 100k, 1MHz, THRU |
| Lower Cutoff Frequency | 1 Hz *can be extended to 0.1 Hz or less |
| Maximum Output Voltage | ±10 V |
*Please contact us in advance for customized products.
