STMicroelectronics Inc. (Geneva) announced its new L6671 rotational acceleration sensor device based on MEMS technology, which addresses applications in HDDs and consumer products. Housed in a standard SO-24 plastic package, the device includes a capacitive rotational accelerometer sensor plus a sensitive interface chip integrating A/D conversion, filtering and interface functions.
It provides a digital output through a 3.3V (5V-tolerant) three-wire serial bus and achieves a signal bandwidth of 800Hz, sensitivity of 2.5rad/s2, a full-scale sensitivity of 200rad/s2, and a 37dB SNR over 30Hz to 800Hz. It is also possible to program device characteristics, including gain, offset, filter performance and phase delay through the serial bus.
Inside the device, movement about the rotational axis causes a displacement of a structure inside the MEMS sensor, producing a capacitive change. These changes in capacitance are converted by the interface chip into a digital output for direct connection to a microprocessor. It can measure capacitance changes as small as 0.05fF.
