1. Calibration of Temperature Sensors in Dynamic and Steady-State Systems
19th Annual Arizona Space Grant Consortium Symposium
Peter Kozak, UA/NASA Space Grant
Mentor: Michael Sampogna
April 17th, 2010

2. Objective To determine the temperature of the light emitting
diodes (LEDs) from the temperature sensor (LM335)
output.
ST- LM335
F. M. Mims III,
An Inexpensive and Accurate Student Sun Photometer
with Light-Emitting Diodes as Spectrally Selective Detectors,
Proceedings of the Third Annual GLOBE Conference, , August 1998.

3. Source: SGS Thompson Microelectronics
The Temperature Sensor
ST LM 335 Transistor
Output: 10mV / K
1 kΩ
V (out) 5V
LM 335
Source: SGS Thompson Microelectronics

4. Procedure
-Steady vs. Dynamic Systems
LED Temperature vs. Sensor Output

6. Steady State Analysis

7. Steady State Linear Regression
For T < 287K,
The error is approximately
constant so the data
points may be averaged.
For T < 287K,
Average Error = 1.66K
Uncertainty (95%Confidence) = +/ K

8. Dynamic State Analysis
Transition to
Steady-State:
T = 300K
Heating =>
<= Cooling

9. Conclusions Dynamic State (T < 300K) Steady State (T > 300K)
Cooling: [T(LED) = (Ts)^ (Ts) ] (K)
Heating: [T(LED) = (Ts)^ (Ts) ] (K)
Steady State (T > 300K)
[T(LED) = 0.841(Ts) ] (K)
Uncertainty
U = +/ K
R = 0.97

10. I would like to thank the following for their support and assistance:
-Michael Sampogna
-Anthony Pitucco
-Forrest Mims III
-Arizona Space Grant Consortium
-University of Arizona
-Pima Community College