Bosch shrinks engine management sensor dramatically

Bosch shrinks engine management sensor dramatically

New Products |
By eeNews Europe

Pressure and temperature data are transmitted across a 12-bit digital interface instead of an analog line — for the first time in Bosch’s SMP product line. This digital barometer’s pressure signal tolerance over its lifetime is less than 1.0 kPa; Bosch claims that this is the best accuracy currently available in the market. The SMP480, which features a ten-pin premold SMD housing and is RoHS-compliant, is already being delivered in large quantities.

The core of the SMP480 is its sensor element. This is made up of a monocrystalline silicon membrane – manufactured using the advanced porous silicon membrane (APSM) process – which hermetically seals a reference vacuum. Four strain gages are implanted in the membrane in a bridge circuit. Changes caused by atmospheric pressure in the curvature of the membrane, even those measuring just a few thousandths of a millimeter, are converted into an electrical signal. Signal conditioning and A-D conversion are performed by an ASIC adjacent to the sensor element within the housing.

Barometric pressure sensors are a key component in engine management for diesel and gasoline engines. They are designed to measure the current ambient pressure accurately and with low drift. Atmospheric pressure is a function of height above sea level as well as of weather conditions. The engine management system uses the sensor measurement data to ensure the optimum air-fuel mixture, irrespective of whether the vehicle is traveling along a coastal road or a road up in the mountains. The benefit of this constant rebalancing of the mixture ratio is that it reduces fuel consumption as well as emissions of CO2 and other pollutants.


If you enjoyed this article, you will like the following ones: don't miss them by subscribing to :    eeNews on Google News


Linked Articles