Skip to content

INA163UAE4: A Low-Noise Instrumentation Amplifier

Amplifiers can make a lot of noise depending on how they are optimized for the target applications. For the best user-experience, it is best to go for the optimization format that limits the extent of the noise it makes.

Using a low-noise amplifier like the INA163UAE4 is a starting point. It is a low-noise, low-distortion, instrumentation amplifier, designed to be used with the applications that require lower noise dissipations.

If you are looking to manufacture medical instruments, industrial or instrumental applications, using the INA163UAE4 will go a long way to reduce the noise dissipation from those devices.

What is a Low-Noise Instrumentation Amplifier?

The two keywords here are low-noise and instrumentation amplifier. An Instrumentation Amplifier or INA for short is a type of amplifier that makes the amplifier to be suitable for use with the applications in the test equipment and measurement markets.

The optimization for those applications is derived from the INA’s outfitting with input buffer amplifiers. This outfitting allows the amplifier to function independently and not rely on the input impedance matching.

For the low-noise operation, the INA163UAE4 derives that from the extreme sensitive design that aids it to measure even the smallest of noise signals in noisy environments.

To even-out or balance the noise, the INA163UAE4 has to rejecting the voltages common to the two inputs, while highlighting the differences between the two as well.

Important Points about the Noise Impedance


Although INA163UAE4 is an Instrumentation Amplifier (INA) and as such, can reduce noise dissipation; there are also some clauses attached to how this works.

First, it provides low-source impedance for lower noise operations, especially via the delivery of a near-theoretical noise impedance with a source impedance of 200Ω.

The clause, however, is that the INA163UAE4 may be unable to deliver the highest levels of noise reduction because of the inability to functionally offer a greater noise performance above a 10kΩ source impedance.

Typical Applications

The typically-supported applications of the Instrumentation Application (INA) include but are not limited to medical, instrumentation and industrial applications.

When it comes to the INA163UAE4, the applications or use cases are even higher. For example, it can be used for the aforementioned applications, as well as for the professional microphone amplifier applications.

In this case, INA163UAE4 is optimized for the low-noise requirements of the applications by offering a combination of the differential input, the low-noise and the low-distortion. These three (3) factors contribute in making INA163UAE4 to be one of the superior-performing Instrumentation Amplifiers (INAs).

In addition to supporting the use in professional microphone applications, INA163UAE4 can also be used with some other audio applications. An example of this is the use in the high-level audio stages. To this end, INA163UAE4 is able to fit into the audio stage applications because of the combined functions of the following:

  • High output current drive
  • Wide supply voltage
  • Excellent output voltage swing

INA163UAE4 can also be used with the following applications:

  • Bridge transducer amplifiers
  • Moving-coil transducer amplifiers
  • Differential receivers

Choosing a Low-Noise Instrumentation Amplifier the Right Way

When we talk about a low-noise Instrumentation Amplifier (INA), we refer to the amplifiers that “don’t make a lot of noise” but yet, they perform optimally.

If you are to choose an INA today, it would be worthwhile to consider some important factors. Here are the major things you want to check before making that buying decision:

1. What is the INA’s Cost?

If an amplifier is to greatly reduce the noise dissipation, the chance is that it would cost more. However, you may be able to save up on costs if you are going for the Instrumentation Amplifier (INA) built with two Operational Amplifiers (Op-Amps).

However, the clause is that the gain for the INA must be greater (up to +6 dB) than the Op-Amps used in the amplifier.

2. The Target Applications

What type of device or application is the INA meant for? Ideally, as it is a low-noise amplifier, it also makes sense that it should be used with the low-noise applications.

The examples of noise-sensitive applications include but are not limited to:

  • Industrial applications
  • Medical applications
  • Instrumentation applications

You can also use the INA like the INA163UAE4 with the professional microphone preamplifiers, ECG (cardiac monitors), data logging systems, power monitoring applications and acoustic transducers.

The other supported applications are sensor conditioning, blood pressure monitors, modal vibration analysis tools and magnetic sensor conditioning tools.

3. The Source Resistance

The source resistance can help you choose an INA, because of the correlation to the noise coming from the amplifier.

For example, if the source resistance is greater than RH, and the current noise dominates, it would be worth it to use an Instrumentation Amplifier (INA) that has a lower current noise.

On the other hand, if the source resistance is less than RL, it is better to use an Instrumentation Amplifier (INA) that has a lower voltage noise, provided, of course, that the voltage noise dominates.

4. Consider the INA’s Building Format

The process of building the Instrumentation Amplifier (INA) is also important. Commonly, the amplifier is built with either the precision resistors or the Operational Amplifiers (Op-Amps).

However, you can also find a couple of INAs built some other way. Companies like Texas Instruments, Maxim Integrated and Analog Devices take a lead in this area. They typically build the INAs in the form of an Integrated Circuit (IC).

The IC design allows for the real-time integration or addition of the INA to the target applications. Besides, it is also a great way to save up on space, especially when the target applications have a smaller circuit board footprint.

5. Be Certain of the Need

We already reeled out a list of the top applications that can be configured with an Instrumentation Amplifier (INA).

The next thing you want to do here is to be certain of the need of an INA in those applications. You want to start by confirming that the circuits of those applications or devices require both the short and the long-term stability and accuracy.

Another consideration to make here is the noise requirements, whereby those applications or systems often need to maintain the highest performance levels, even when they are operating in noisy environments.


Use the INA163UAE4 to highlight the performances of different high-end applications, especially where these applications need to keep up with these performance levels, despite being in between large common-mode voltages and noisy environments.