Differential Amplifiers

Differential amplifiers are used to measure the voltage difference between two signals while ignoring any shared noise or interference. This makes them useful for high-precision measurements, especially in environments where signal integrity matters.

ValueTronics carries a variety of differential amplifiers, including high-speed and low-noise models from trusted brands. Our inventory includes both new and refurbished options to fit different performance needs and budgets. Each unit is tested for reliability, and our team can assist in finding the right amplifier for your application.

8 products

Frequently Asked Questions

What are differential amplifiers used for?
Differential amplifiers are used in test setups where signal accuracy is important. They help isolate and amplify the voltage difference between two inputs, making them useful for rejecting noise and interference picked up in measurement systems. These amplifiers are often used in oscilloscope applications, sensor testing, and environments where small signals need to be measured across noisy or high-voltage systems.
What is the difference between a normal amplifier and a differential amplifier?
A standard amplifier increases the amplitude of a single input signal. A differential amplifier, on the other hand, measures the voltage between two inputs and amplifies that difference. It rejects any voltage common to both inputs, which helps eliminate noise or interference that appears equally on both lines. This makes differential amplifiers more suitable for precise, low-level measurements in complex or noisy environments.
What specifications should I look for in a differential amplifier?
Important specifications include bandwidth, gain range, input impedance, and common-mode rejection ratio (CMRR). Bandwidth determines how fast the amplifier can respond to changes in the input signal. Gain controls how much the signal is amplified. A high CMRR means the amplifier is better at rejecting unwanted noise. Input impedance should match your measurement system to avoid signal distortion. Some applications may also require features like adjustable offset or selectable filters.
Can a differential amplifier be used with both AC and DC signals?
Yes, most differential amplifiers are designed to handle both AC and DC inputs. This flexibility allows them to measure a wide range of signals, from steady voltage levels to rapidly changing waveforms. Some models offer selectable coupling modes, so you can choose to block DC offset or pass both components depending on the test setup. Always check the specifications to confirm compatibility with the signal type you're working with.
How do I connect a differential amplifier in my test setup?
To connect a differential amplifier, use two input leads to attach to the signal points you want to measure. These leads should connect across the voltage difference you’re targeting. The output of the amplifier then connects to your measurement device, such as an oscilloscope or data acquisition system. Make sure the input range, impedance, and grounding are compatible with the system to avoid distortion or damage.
What maintenance or calibration is required for differential amplifiers?
Differential amplifiers generally require minimal maintenance, but regular calibration is recommended to maintain accuracy over time. Calibration intervals depend on usage and manufacturer guidelines. It's important to keep connectors clean, store the amplifier in a controlled environment, and check for any signal drift or unexpected output. ValueTronics offers calibrated units and can assist with service options if ongoing support is needed.