SMTAS08

SMTAS08 Smartec Temperature Acquisition system Ver: 05 Januari 2003 SMart Temperature Acquisition System for 08 channels SMTAS08 Smartec © 2002, 2003 1 SMTAS08 Smartec Temperature Acquisition system Ver: 05 Januari 2003 Contents. 1. Introduction 2. Quick start and functional check 3. Inside the SMTAS08 system - General - Selfheating of the temperature sensor - Measurement accuracy 4. Circuit diagram and connections to the board - Circuit diagram - Connector layout 5. SMTAS08 software - Hyperterminal - Labview - Visual basic 6. Ordering information Smartec © 2002, 2003 2 SMTAS08 Smartec Temperature Acquisition system Ver: 05 Januari 2003 1. Introduction This document describes an 8 channel temperature measurement system: The Smart Temperature Acquisition System(SMTAS08). It is based on the use of the Smart-temperature sensors SMT160 of Smartec. The SMT160 is a three-terminal integrated temperature sensor with a duty cycle output. Two terminals are used for the power supply of 5 volts and the third terminal carries the output signal. The output signal of the sensor is a duty-cycle-modulated square-wave signal (see Figure 1). t1 t2 Figure 1 (a) Output signal of the SMT, (b) Relation between the duty-cycle and the temperature. After measuring both t1 and t2, the temperature in 0C can be calculated by equation: θ = t1 − 68.09 0.0047t 2 The temperature sensors are sold separately from the SMTAS08 board, because the SMT 160-30 temperature sensor is available in differen...