PA560 Low-Noise Voltage Preamplifier with 1MHz Bandwidth for Weak Signal Processing

3 nV/√Hz input noise (typical)

1MHz maximum bandwidth

Low 1/f noise corner frequency: 10Hz

Variable gain range: 1 to 50,000 (1-2-5 sequence)

AC or DC coupling

Two configurable bandwidth filters (low-pass/high-pass)

Differential or single-ended input

External power supply or battery operation

The PA560 is a high-performance, low-noise voltage preamplifier designed for amplifying low-frequency weak signals. It features configurable bandwidth and gain, making it suitable for a wide range of applications including cryogenic measurements, low-frequency noise measurement in chips, sensor detection, photoelectric detection, audio engineering, and vibration analysis.

The instrument can be used standalone or integrated with other equipment such as oscilloscopes, lock-in amplifiers, and dynamic signal analyzers.

Input

The PA560 features true differential input mode with an input noise spectral density of 3nV/√Hz (50Ω shorted) and an input impedance of 100MΩ. The input is fully floating (BNC shield not connected to chassis ground). Input offset voltage nulling can be achieved via a front-panel potentiometer, adjustable with a small screwdriver.

Output

Two isolated output BNC connectors provide 600Ω or 50Ω output impedance. Both are capable of delivering a maximum signal of 10 Vpp to drive subsequent loads.

Filter

The PA560 includes two programmable first-order RC filters, enabling five filter mode configurations through different combinations: LPF (6dB/oct), BPF (6dB/oct), HPF (6dB/oct), LPF (12dB/oct), and HPF (12dB/oct). Filter mode and cutoff frequency can be set via the front panel, with frequency ranges from 0.03Hz to 1MHz, increasing in a 1-3 sequence (e.g., 3Hz, 10Hz, 30Hz, 100Hz...).

Gain

Gain can be set in a 1-2-5 sequence, selectable from 1 to 50,000. Two gain modes are available: low-noise mode allocates gain before the filter to optimize noise performance, while high-reserve mode allocates gain after the filter to reduce sensitivity to signal overload.

Battery Operation

In addition to 220V AC mains operation, the instrument features built-in battery power. Battery mode significantly reduces power frequency interference, conducted disturbances, and wireless coupling interference, making it ideal for field applications.

The rechargeable lithium battery provides up to 10 hours of operation. It charges automatically when connected to an external power supply, with a charging time of 4 hours. The front-panel LED indicates the battery charging status.