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university:courses:electronics:electronics-lab-window-comp-tmp01 [07 Mar 2018 13:14]
Antoniu Miclaus
university:courses:electronics:electronics-lab-window-comp-tmp01 [03 Jan 2021 22:21]
Robin Getz fix links
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 ===== Objective ===== ===== Objective =====
  
-The objective of this lab activity is to use two high speed voltage comparators as a Window-Comparator and program the [[http://​www.analog.com/​media/​en/​technical-documentation/​data-sheets/​TMP01.pdf|TMP01]] ​Low Power Programmable Temperature Controller using this approach.+The objective of this lab activity is to use two high speed voltage comparators as a Window-Comparator and program the TMP01 Low Power Programmable Temperature Controller using this approach.
  
 A Window-Comparator is a circuit configuration,​ usually consisting of a pair of voltage comparators (inverting and non-inverting),​ in which the output indicates whether an input signal is within the voltage range bounded by two different thresholds. One which triggers an op-amp comparator on detection of some upper voltage threshold, V<​sub>​REF(HIGH)</​sub>​ and one which triggers an op-amp comparator on detection of a lower voltage threshold level, V<​sub>​REF(LOW)</​sub>​. The voltage levels between these two upper and lower reference voltages is called the “window”. A Window-Comparator is a circuit configuration,​ usually consisting of a pair of voltage comparators (inverting and non-inverting),​ in which the output indicates whether an input signal is within the voltage range bounded by two different thresholds. One which triggers an op-amp comparator on detection of some upper voltage threshold, V<​sub>​REF(HIGH)</​sub>​ and one which triggers an op-amp comparator on detection of a lower voltage threshold level, V<​sub>​REF(LOW)</​sub>​. The voltage levels between these two upper and lower reference voltages is called the “window”.
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 ==== Procedure ==== ==== Procedure ====
  
-Use the first waveform generator (W1) as source to provide a Triangular signal with 5V amplitude, 100Hz frequency and 2.5V offset.+Use the first waveform generator (W1) as source to provide a Triangular signal with 5V amplitude ​peak-to-peak, 100Hz frequency and 2.5V offset.
  
 Use the second waveform generator (W2) as 5V constant reference voltage. Use the second waveform generator (W2) as 5V constant reference voltage.
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 R<​sub>​3</​sub>​ (in kΩ) = V<​sub>​SETLOW</​sub>/​I<​sub>​VREF</​sub>​ R<​sub>​3</​sub>​ (in kΩ) = V<​sub>​SETLOW</​sub>/​I<​sub>​VREF</​sub>​
  
-The total R<​sub>​1<​sub>​ + R<​sub>​2</​sub>​ + R<​sub>​3</​sub>​ is equal to the load resistance needed to draw the desired hysteresis current from the reference, or I<​sub>​VREF</​sub>​.+The total R<​sub>​1<​/sub> + R<​sub>​2</​sub>​ + R<​sub>​3</​sub>​ is equal to the load resistance needed to draw the desired hysteresis current from the reference, or I<​sub>​VREF</​sub>​. 
 + 
 +I<​sub>​VREF</​sub>​ = 2.5V/( R<​sub>​1</​sub>​ + R<​sub>​2</​sub>​ + R<​sub>​3</​sub>​) 
 + 
 +Since VREF = 2.5 V, with a reference load resistance of 357 kΩ or greater (output current 7 μA or less), the temperature setpoint hysteresis is zero degrees. Larger values of load resistance only decrease the output current below 7 μA and have no effect on the operation of the device. The amount of hysteresis is determined by selecting a value of load resistance for VREF.  
 + 
 +==== Tasks ==== 
 + 
 +1. Build the following circuit: 
 + 
 +<WRAP centeralign>​{{:​university:​courses:​electronics:​tmp01-bb1.png|}}</​WRAP>​ 
 + 
 +<WRAP centeralign>​ Figure 5 Temperature Measurement </​WRAP>​ 
 + 
 +Measure VPTAT output value and compute the actual measured temperature in degrees Kelvin and degrees Celsius. 
 + 
 +2. Build the following circuit: 
 + 
 +<WRAP centeralign>​{{:​university:​courses:​electronics:​tmp01-bb2.png|}}</​WRAP>​ 
 + 
 +<WRAP centeralign>​ Figure 6 Temperature Control </​WRAP>​ 
 + 
 +2.a. Identify the components and try to draw the circuit schematic. 
 + 
 +2.b. Using the information provided by the breadboard circuit, compute the following parameters:​ 
 + 
 +  * I<​sub>​VREF</​sub>​ 
 +  * V<​sub>​SETHIGH</​sub>​ 
 +  * V<​sub>​SETLOW</​sub>​ 
 +  * T<​sub>​SETHIGH</​sub>​ 
 +  * T<​sub>​SETLOW</​sub>​ 
 + 
 +2.c. How many degrees is the temperature setpoint hysteresis? How can you change this value? 
 + 
 +2.d. How does the circuit work? When will LED1 (red) and LED2 (blue) turn on? Explain your answer. 
 + 
 +<WRAP round download>​ 
 +**Lab Resources:​** 
 +  * Fritzing files: [[downgit>​education_tools/​tree/​master/​m2k/​fritzing/​temp_ctrl_bb | temp_ctrl_bb]] 
 +  * LTspice files: [[downgit>​education_tools/​tree/​master/​m2k/​fritzing/​temp_ctrl_ltspice | temp_ctrl_ltspice]] 
 +</​WRAP>​ 
 +===== Further Reading ===== 
 + 
 +Additional resources:​ 
 + 
 +  * [[adi>​static/​imported-files/​data_sheets/​TMP01.pdf|TMP01 Low Power Programmable Temperature Controller]] 
 +  * [[adi>​library/​analogdialogue/​archives/​42-10/​testing_comparators.html|Adding Test Capability to a Window Comparator]] 
 + 
 +**Return to Lab Activity [[university:​courses:​electronics:​labs|Table of Contents]]** 
 + 
 + 
 + 
 + 
 + 
 + 
 + 
  
-I<​sub>​VREF</​sub>​ = 2.5/( R<​sub>​1</​sub>​ + R<​sub>​2</​sub>​ + R<​sub>​3</​sub>​) 
  
university/courses/electronics/electronics-lab-window-comp-tmp01.txt · Last modified: 03 Jan 2021 22:21 by Robin Getz