ANALOGUE TO DIGITAL CONVERTER WITH NON-LINEAR TRANSFER FUNCTION FOR THERMISTOR APPLICATIONS
R.K. Kamat, G.M. Naik
Abstract:
There exists a disproportionate difference between dynamic range, resolution, and accuracy when the output of sensors having nonlinear characteristics like thermistors are digitized with the conventional linear ADCs. There are several methods to linearise the thermistor characteristics but at the expense of hardware, memory and time efficiency. This paper presents a new simple method of shaping the transfer function of a pulse width modulation ADC as per the thermistor characteristics. It is based on the principle of varying the amplitude of the reference voltage to reach the temperature equivalence of voltage being digitized.
Keywords:
thermistor, PWM ADC, PSpice, NADC, transfer function
4th International Conference on Advanced A/D and D/A Conversion Techniques and their Applications (together with 7th IMEKO TC4 Workshop on ADC Modelling and Testing)
