Q&A - What is the importance of an op-amp having a high peak power capability - Apex

September 17, 2020

Question

What is the importance of an op-amp having a high peak power capability? 

Answer

A high peak power capability makes the op-amp suitable for applications that temporarily require high (pulsed) output power, such as in Automated Test Equipment (ATE, DUT can be defective!) or Sonar. Depending on the average power required, the continuous power capability of the op-amp can be much less than the peak power. Dynamic loads, like gimbals or flight control actuators, also benefit from high peak power capabilities. These applications demand high power levels quickly when an external disturbance, such as wind or acceleration, interacts with the payload. An Op-Amp's peak power is used to deliver quick correction to counteract such disturbances by driving the load in equally (or to some determined level) in the opposite or desired direction.

Introducing the PA22, high voltage, high current output, high power dissipation

PA22 has a very high peak power capability through its distribution of heat-dissipating components across a large percentage of the substrate surface area. Following Fourier's law, thermal resistance decreases with increasing surface area, a key principle incorporated into the PA22's design. Its large heat-tab also aids in power dissipation and heat conduction by providing a low-thermal-resistance path to a heatsink, therefore minimizing the temperature rise per Watt. The PA22's fast clamping current limit response shortens the time through which the PA22 is potentially under current load stress, preventing the current output of the PA22 from exceeding the SOA. Finally, the PA22 also has a provision to measure the output die temperature, which may allow for harder drive through better control.