The IMPLEMENTATION OF TEMPERATURE SENSOR THREE POINTS VOLTAGE CALIBRATION USING LINEAR EQUATION METHODOLOGY ON C90NM MICROCONTROLLER (MPC5674F) FOR TEST YIELD IMPROVEMENTS
Semiconductor Test And Measurement
Abstract
This paper study the problems related to the current methodology of temperature sensor two-points voltage calibration on MPC5674F microcontroller where this current method is ineffective leading to package test low yield of temperature sensor test. The focus on this paper is about implementing a new methodology known as the temperature sensor three-points voltage calibration by using a linear coefficients concept, where the method is to apply a fixed slope of temperature response base on one control room temperature from wafer level probe to determine the hot and cold temperature voltage at package test with C++ test program code. The current production data shows the calibrated temperature sensor not within ±10°C accuracy in the temperature range of 25°C to 145°C based on current methodology. To implement new methodology, characterization work were carried out using good units on three different slopes 25°C to -40°C, 25°C to 100°C and 100°C to -40°C. The best fit slope 100°C to -40°C results of 0.006055v was selected to use for the temperature sensor three-points voltage calibration methodology to represent the actual operating condition of microcontroller at temperature range of -45°C to 145°C due to its consistency at temperature range. Yield and analysis results are discussed using the new methodology to evaluate the improvements which can reduce the scrap cost.