Piezoelectric acceleration sensor esp. for safety devices - has switched capacitor between transducer and integrator to eliminate high impedance resistors

摘要

A piezoelectric acceleration sensor contains a piezoelectric transducer (6) connected via a resistance to the input of an integrator (14) in an evaluation circuit. The resistance is formed by a first capacitor (C1) connected in parallel with the transducer and a switch (S1) connected to the capacitor and alternatively connected to the transducer or integrator. The integrator is an operational amplifier with a negative feedback path contg. a second capacitor (C2) and parallel switch (S2). USE/ADVANTAGE - Triggering passenger safety equipment in motor vehicles. Modified to eliminate high resistances and produce more compact design.