AN1827 Datasheet, PDF (1/11 Pages) STMicroelectronics – IMPLEMENTATION OF SIGMA-DELTA ADC

AN1827
APPLICATION NOTE
IMPLEMENTATION OF SIGMA-DELTA ADC
WITH ST7FLITE05/09
INTRODUCTION
The purpose of this document is to describe how to implement a 10-bit Sigma-Delta A/D con-
verter using a simple external circuit and a Sigma-Delta conversion program.
The ST7FLITE05(09) has an on-chip ADC with 8-bit resolution and an input range of 0-V_CC.
The external Sigma-Delta ADC described in this application is designed for relatively slow al-
ternating signals (0,2 - 5Hz) in the range 0 - 10mV(p-p). The focus of the project is to provide
good relative accuracy, repeatable parameters and simplicity, resulting therefore a low cost of
the device (in its simplest form, apart from the microcontroller, only three RC elements are
necessary).
AN1827/0304
Rev. 1.0
1/11
1