Allegro introduces sensor interface IC for resistive bridge pressure sensors

Allegro MicroSystems has introduced the A17700, an automotive-grade interface IC for resistive bridge pressure sensors featuring signal conditioning algorithms.

The A17700 is configurable for resistive bridge pressure sensors in a wide range of critical automotive applications, from high-pressure systems like dynamic brake systems (DBS) in turbo and hybrid electric vehicles (HEV) or gasoline direct injection (GDI) to medium and low-pressure systems such as brake boosters, HVAC applications for electrified vehicles, and automatic transmission oil management.

With its integrated polynomial algorithm, the A17700 interface sensor offers high accuracy over pressure and temperature through two-stage processing of a pressure signal. This flexible compensation delivers high accuracy in resistive membranes requiring either high- or low-point characterisation during assembly.

The device has been designed to offer several ways to improve system output and maintain flexibility. With robust EMC performance – up to 4kV HBM – the A17700 enables up to 30% fewer external components for a smaller total solution footprint, smaller PCB, and more cost-efficient system design.

With parallel processing paths for input and temperature, the A17700 can achieve the smallest chip delay on the market. With an input-to-output processing delay of 100 μs, this ultra-fast interface sensing IC allows systems to compensate for vibration effects on the membrane with no output resolution loss, further increasing system fidelity.

Environmental conditions, such as a change in supply voltage level, temperature, input bridge signal, and connection, can cause temporary faults in pressure sensing systems. The A17700 is able to capture these changes and signals them in the output protocol, enabling fault filtering at the system level for more accurate safety notifications.

The A17700 is available in a small form-factor 24-pin 4 mm × 4 mm QFN package with wettable flanks - and is suitable for ensuring reliable soldering and visual inspection of solder joints.