Allegro introduces high-precision, high-output flexibility sensor interface ics for resistive bridge pressure sensors

Allegro, a global leader in sensing technology and power semiconductor solutions for motion control and energy saving systems, announced the introduction of the automotive grade interface IC A17700 for resistive bridge pressure sensors, which builds on Allegro's decades of automotive sensor expertise. Industry-leading signal conditioning algorithms and flexible interface options are integrated to deliver superior performance and higher system efficiency, all in a small package size.

The A17700 has several market-leading features, including:

● Flexible compensation algorithm that can be used to maintain accuracy against temperature changes and detect bridge changes

● Provide accurate pressure information through low-delay analog, PWM or SENT outputs

● Meets automotive AEC-Q100 Grade 0 certification and EMC robustness requirements with minimal external components

● A full set of advanced integrated system diagnostic functions

The A17700 can be configured with resistive bridge pressure sensors for a variety of critical applications in today's efficient automotive designs, from high pressure systems such as turbocharging, hybrid electric vehicles (HEV), or gasoline direct injection (GDI) dynamic braking systems (DBS). To medium and low pressure systems such as brake boosters, electric vehicle air conditioning systems (HVAC) and automatic transmission fluid management.

Flexible compensation technology for high-precision output

With its best-in-class integrated polynomial algorithm, the A17700 sensor interface processes pressure signals in two stages, providing greater accuracy over pressure and temperature ranges. This flexible compensation technology enables higher precision for resistance films that require high - or low-point characterization during assembly.

The A17700 offers a variety of ways to improve system output while maintaining a high degree of flexibility, thus achieving the perfect balance desired by system designers. With robust EMC performance of up to 4kV HBM, the A17700 is also able to reduce external components by up to 30%, enabling smaller solutions, reduced PCB size, and improved cost performance for system designs.

Haeyoung Choi, Product Manager for Sensor Interface ics at Allegro, explains: "The A17700 enables system designers to easily select the best algorithms and I/O options for their specific requirements, enabling the best balance between accuracy and end of line test time to optimize system costs. With its small footprint and flexible compensation technology integrated, the A17700 is the ideal solution for space - and efficience-critical applications such as today's electric and hybrid vehicles."

Analog or digital standard interfaces enable fast output responses

With parallel processing paths for input and temperature, the A17700 achieves the lowest chip latency on the market today. This ultra-fast sensor interface IC features an input-to-output processing delay of 100 µs, allowing the system to compensate for the effects of oscillations on the film without reducing output resolution, further increasing system fidelity.

Choi added, "The A17700's fast response time speeds up the output sampling rate, which allows the system to filter out unwanted membrane oscillating signals. This enhanced oscillation filtering capability ensures the most appropriate filtering and provides reliability and performance that customers can rely on."

Complete diagnostic capabilities for safety-critical systems

Changes in conditions such as power supply voltage, temperature, input bridge signals and connections can cause temporary failures in the pressure sensing system. The A17700 captures these changes and flags them in the output protocol, enabling fault filtering at the system level to provide more accurate security notifications.