New Industry Products

First Noise-Tolerant Opamps for Automotive Systems

November 15, 2017 by Paul Shepard

ROHM has announced the availability of automotive-grade ground sense opamps that deliver breakthrough EMI tolerance (noise immunity) for automotive systems using sensors along with core systems for EVs and HEVs.

Applications are expected to include EV / HEV inverters, ECUs, Automatic transmissions, Electric power steering, Automotive lamps, Automotive air conditioning, EV chargers, Car navigation, Combination switches, and other vehicle electrical systems and circuits affected by noise.

Developed using 3 proprietary analog technologies (layout, processes, circuit design), the BA8290xYxx-C series features superior noise immunity that suppresses output voltage fluctuation in all frequency bands to less than ±1%, compared to ±3.5% to ±10% with conventional products.

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As a result, installing in the subsequent stage of devices that output micro-signals such as sensors will make it possible to amplify signals without being affected by noise, eliminating the need for noise countermeasures such as filters. This helps to reduce design load while contributing to greater reliability.

The latest automotive systems achieve greater fuel economy and safety by adopting ECUs and sensors that manage and optimize conditions such as temperature, acceleration, and current.

At the same time the move towards greater digitization and application density in automotive systems has increased the amount of noise generated in the environment, presenting significant problems for sensors and other small-signal devices.

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What's more, during automotive development it is extremely difficult to evaluate individual sources of noise, making it necessary to perform noise evaluation after installation.

So unless careful attention is paid to noise design, major modifications (entailing increased costs and development time) may be required if the application fails testing.

In response, ROHM has developed the world's first opamps that eliminate the effects of noise in automotive sensor applications by utilizing a vertically integrated production system that leverages analog design technology and proprietary bipolar processes.

Samples are available immediately with production scheduled for June 2018. Key features include:

  1. The world's first opamps that eliminate the need for noise countermeasures

The BA8290xYxx-C series utilizes 3 proprietary analog technologies: circuit design (new noise countermeasure circuit), layout (based on market-proven analog expertise), and (bipolar) processes to achieve breakthrough noise immunity that limits output voltage fluctuation to less than ±1%, compared to ±3.5% to ±10% with conventional products.

This reduces the number of components required for noise suppression (3 CR filters for the input/output/power supply), meeting noise-related challenges in the development of automotive electrical systems while contributing to lighter design load and higher reliability.

In the future ROHM also plans on supplying high noise immunity opamps for the industrial market.

  1. Supports automotive requirements worldwide

The entire lineup is AEC-Q100 qualified, ensuring automotive-grade reliability, and delivers superior current consumption (0.5mA vs conventional 0.7mA) and offset voltage (±6mV vs ±7mV) in a range of standard package types, channels, and layout - enabling easy replacement with existing products to reduce noise.

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