ST Introduces Pair of Rugged Op-Amps for Automotive Landscapes

September 12, 2023 by Aaron Carman

STMicroelectronics’ latest op-amp can handle the heat while keeping its operating point static.

STMicroelectronics has announced its TSZ18xH1 line of rugged operational amplifiers targeted at new industrial applications. As electronics are deployed in denser and harsher environments, a high-accuracy op-amp can not only speed development time but simplify operation.


ST's new op amps, the TSZ18XH1 chips

With industrial-grade specs across a wide operating range, the latest ST op-amp gives designers the ability to implement precision instrumentation in industrial and automotive settings. Image (modified) used courtesy of STMicroelectronics

As a key piece of analog electronics, operational amplifiers can often be taken for granted because they can be simplified into “ideal” components. In applications requiring high accuracy over a wide operating range, however, this ideal model can quickly decay into one that creates lasting headaches for the designer. As such, the ST TSZ line of op-amps can make designers’ lives easier by providing precise operation across industrial environments.

This article breaks down the key specs of the TSZ181H1 and TSZ181H2 to give engineers the critical details behind the chips. In addition, we will discuss the chips’ usefulness in industrial environments to give readers a sense of how they can use the chip for their latest industrial analog electronics.


Op Amps Built for Tough Environments

When designing electronics, engineers conform to certain standards to ensure that the end devices operate well in all environments. These standards vary by sector, but in both consumer and industrial electronics, temperature, ESD robustness, and general durability are key requirements.

Where the two markets differ, however, is the extent to which the devices must be qualified. Industrial electronics must be qualified across a broader temperature range than their consumer counterparts to maintain production throughput and safety. Other safety-critical applications, such as automotive electronics, demand similar standards.



For safety-critical automotive and industrial applications, the low input offset voltage across the entire operating range makes the TSZ18XH1 chips useful for high-accuracy instrumentation. Image used courtesy of STMicroelectronics

While many companies offer industrial and automotive-grade electronics, the operating point can change drastically across the temperature range, creating inaccuracies that limit the performance of the system. The new TSZ line, however, features precise specs across the broad temperature range.


Temperature Agnostic Op-Amps

Perhaps the most noteworthy spec from the datasheet is the devices’ performance over the entire operating range. In terms of input offset voltage, the device ranges from 3.5 µV to 44 µV over the entire temperature range, with an associated 225 pA max input bias current.


The phase margin of the TSZ18XH1 chips

The phase margin of the TSZ18XH1 chips makes them useful for applications where stability is necessary across the entire operating range. Image used courtesy of STMicroelectronics

The op-amps also show good stability over the operating range, with a worst-case phase margin of 56° in ST’s tests. The gain bandwidth is also adequate for many applications, with 2.3 MHz being the lowest reported at a lower supply voltage. Both the single and dual op-amp packages are qualified under the AEC-Q100 standard and report 4 kV HBM ESD tolerance.

The op-amps come in two packages: the TSZ181H1, including a single op-amp in an SOT23-5 package, and the TSZ182H1, containing two op-amps in an SO8 package. Both chips operate within -40°C to 175°C, with a supply voltage range from 2.2 V to 5.5 V.


TSZ Is Designed for Industrial Precision

ST's new TSZ line lengthens the list of applications for which the family can be used. As electronics become more densely deployed in harsh environments such as engines and industrial machinery, a precise op-amp at 175°C can open the door for new innovations. While ST has identified high-accuracy signal conditioning and current measurement as two specific applications that could benefit from the new chips, the TSZ18XH1 op-amps could see considerably more use with its wide operating range.