8

TMP63

SNIS211A – OCTOBER 2019 – REVISED DECEMBER 2019

www.ti.com

Product Folder Links: TMP63

Submit Documentation Feedback

Copyright © 2019, Texas Instruments Incorporated

7 Detailed Description

7.1 Overview

The TMP63 series of silicon linear thermistors has a linear positive temperature coefficient (PTC) that results in a

uniform and consistent temperature coefficient resistance (TCR) across a wide operating temperature range. To

fabricate the TMP63, a special silicon process is used where the devices key characteristics—the temperature

coefficient resistance (TCR) and nominal resistance (R25)—are controlled by the doping level and active region

area. Note that the TMP63 has an active area and a substrate due to the polarized terminals of the device. The

positive terminal should be connected to the highest potential, while the negative terminal should be connected

to the lowest potential.

The TMP63 is different from a NTC, where a NTC is a purely resistive device, the TMP63's resistance is affected

by the current across the part and will change with temperature. In a voltage divider circuit, it is recommended

that the top resistor is kept at 100 kΩ. Changing the top resistor or the VBIAS will change the resistance vs

temperature table (R-T table) of the TMP63, and subsequently the polynomials as described in Design

Requirements. Consult the TMP63 R-T table section for more information.

Equation 1 can help the user approximate the TCR.

(1)

Below are the definitions of the key terms used throughout this document:

•

•

•

•

•

7.2 Functional Block Diagram

Figure 10. Typical Implementation Circuits