Sensor signal conditioner integrates 26-bit DSP
Designed for consumer barometric pressure and thermopile sensors, Integrated Device Technology has introduced an energy-efficient 24-bit Sensor Signal Conditioner (SSC) IC. The ZSSC3224, which integrates a 26-bit DSP for linearisation and calibration functions, is optimised for high-resolution consumer, industrial, white goods, medical and mobile applications.
Developed at recently acquired ZMDI, the ZSSC3224 expands a family of SSCs for high-end sensor modules. Offering both accuracy and high resolution, the sensor interface delivers high-accuracy amplification and a 24-bit precision full-featured ADC.
With a 24-bit output signal, the ZSSC3224 is suited for high-precision measurement systems, including barometric altitude measurement for portable navigation or emergency call systems, altitude measurement for car navigation, pressure measurements inside hard disks and weather forecasting equipment. The device, available in die and wafer form, can also adapt thermopile sensors to enable contactless temperature measurements of objects or human body temperature.
The ZSSC3224 offers features targeting battery-driven, low-power devices, such as 1mA typical overall current consumption, ultra-low 20nA typical sleep mode current and a 1.68 to 3.6V power supply range. Featuring an intelligent power-save scheme to help ensure the lowest overall current consumption, the device also offers internal filter options for low noise output signals and intelligent alarm and interrupt capabilities. The ZSSC3224 eliminates the need for an external buffer capacitor and it provides a superior PSRR of up to 90dB at 2V, making it attractive for applications in harsh environments.
Michael Georgi, Product Marketing Manager, IDT, commented: “We designed the ZSSC3224 to provide our customers with the high resolution and miniaturised form factor needed for their next-gen products. The device is designed for use with resistive pressure sensors as well as absolute voltage sensors such as thermopiles. A stacked die assembly, combined with a dedicated MEMS sensor element, can provide the lowest form factor on the market for MEMS-based sensors.”
Digital compensation of signal offset, sensitivity, temperature and non-linearity is accomplished via an internal correction algorithm with coefficients stored on-chip in a highly reliable, nonvolatile, programmable memory.