Threading the needle: new op amp delivers exceptional precision, accuracy

Precision affects every part of our lives – from ordering lunch meat at the deli to calibrating delicate lab equipment.

And a new high-precision operational amplifier – a circuit that magnifies tiny electric currents so that they can be measured and managed – offers an exceptional level of accuracy in industrial, automotive, medical, personal electronics, and test-and-measurement equipment.

 OPA388: Precision operational amplifier

“The performance on this device is so precise that it’s like measuring a dime on the Empire State Building,” said Richard Barthel, a systems engineer who worked on the team that developed the OPA388. “It takes something very small and gets it right on target.”

Operational amplifiers – or op amps – are links between sensors that measure analog signals such as pressure, temperature and flow and the digital brains behind technologies that are so integral to our everyday lives.

Sensors pick up analog signals from the environment around us that in many cases are measured in the millionths of a volt – too small to be useful for the circuits that convert them to digital signals. The job of op amps is to boost those signals to higher voltages that can then be measured, interpreted and managed by computers.

In that amplification process, any variation in the signal gets progressively more distorted as it works its way through the subsequent signal chain. That, in turn, affects the precision of the final measurements produced by a piece of equipment, said Ying Zhou, product marketing manager for the device.

Our zero-drift and zero-crossover technologies – which our newest op amp combines in one device for the first time – correct for any noise and errors in the signals and remove the need for designers to add discrete calibration circuits to the systems they create.

Combining these technologies will lead to improvements in the accuracy of measurements in applications ranging from electronic scales to heart-rate monitors and pressure sensors. For example, the device’s precision is beneficial for equipment such as:

  • Gauges used in CT scan machines. This medical equipment requires a smooth and consistent movement so the weight and weight distribution of patients can be measured precisely, a critical factor in accurate diagnosis and treatment.
  • Construction equipment. Contractors, civil engineers or other workers will be able to measure elevation and distance with pinpoint precision during building construction, which could increase structural integrity.
  • Weigh scales. Achieve more precise weight measurements – whether you’re ordering a few slices of lunch meat at a deli or checking the weight of a fully loaded semi-truck.
  • Medical lab equipment. Smaller equipment and more precise diagnoses could mean less time in the clinic and more accurate diagnoses for patients.

“Precision affects everybody,” Richard said. “The OPA388 takes very small measurements and gets them right on target with high accuracy and resolution. It threads the needle.”

If you are interested in learning more, read these TI Tech Notes regarding the features and benefits of zero-drift and zero-crossover technologies.