Questions tagged [temperature-coefficient]
18 questions
7
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3 answers
Ultra simple oven controlled resistor for analog temperature control
Background:
We're having a problem with a sensitive analog circuit. It has an analog supply voltage from a LT3045 Linear Regulator, whose output voltage is set by an external resistor. We're using 10ppm temperature coefficient resistors, but even…
Rocketmagnet
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1 answer
How to understand B values of thermistors for different temperature levels?
E.g. the datasheet of NCU18XH103F6SRB mentions different B values for pairs of temperatures (reference temperature to a higher one).
For reference, here the values of this…
Torsten Knodt
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3
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1 answer
Which temperature sensitive material would be a good choice for temperature measurement from 4K to 300K?
I am building a thermometer for a cryostat which operates at low temperatures (until 4 kelvin).
I would like to know the temperature of some parts in my cryostat during the cooling (so from 300 K to 4 K). The idea is to send a small current (in…
Nicolas Schmid
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1
vote
1 answer
What is the mathematical relationship between motor velocity constant, Kv and temperature?
From textbook, it is stated that Kv = rpm/V. But how does Kv change with temperature mathematically?
user150518
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1
vote
1 answer
DC current rating of copper wire (SWG)
I want to use SWG-sized copper wire but I am a little bit confused about the following:
On the internet I found different charts with different maximum current ratings for the same wire diameter. The maximum current obviously depends on the…
Rens
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3 answers
Low-frequency high.pass filter drifts with temperature
for a phase sensitive measurement, I would like to have the DC offset of a signal cancelled. The AC-signal will be amplified and then the phase of it is measured in reference to another AC-signal.
My attempt was using a Sallen-Key-Highpass filter…
T.K.
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1
vote
3 answers
Zener diode as temperature sensor
I am trying to measure the temperature of a battery pack using Zener diodes.
I want to use Energus's Tiny BMS 30A. In their battery modules they use Zener diodes to measure the temperature of the pack like this:
I want to copy their design as it is…
Eirik
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1
vote
1 answer
Temperature drift on volatge divider built with resistors from the same series
I am in the process of designing a data acquisition device that will be used outdoors, with temperature swings of around 30 degrees.
For this i need to scale the input to a voltage suitable to the adc and reference i am using, the initial offset of…
diegogmx
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0
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1 answer
Single Letter Temperature Coefficient for Capacitors?
A certain parts supplier offers ceramic capacitors with temperature coefficients (tempcos) of single letters -- A, E, and so on -- but I cannot find any information on what these letters specify. (The example below suggests that E is equivalent to…
calcium3000
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0
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1 answer
Current source temperature stability
I want to implement an interesting current source topology that I came across recently (picture below). It shows very good performance in simulation and the only thing I am concerned of is its temperature stability. As far as I understand the key is…
Tolik4
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0
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1 answer
Using BS270 MOSFET as Temperature Sensor
I have previously asked a question about using thermocouples to maintain a temperature range of 36-39° inside an insulated and dry environment.
The more enlightened engineers advised I look into using either a semiconductor device or an RTD…
Aaron Butkovich
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Does a diode's tempco vary with temperature?
A pressure sensor's datasheet (https://meritsensor.com/assets/documents/pdf/HM-series.pdf) says its optional temperature sensing diode has tempco between -4mV/K and -1mV/K for -40° to 150°C. I was under the impression a diode's tempco is -2mV/K,…
Hyp
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3 answers
Why is resistor temperature coefficient given in a +/- number?
For a given resistor you might see a TCR of +/-25ppm/C, but I'm not sure I quite understand that number. As far as I know, a PTC resistor like a basic thick film always increases in resistance as temperature rises. So where's the +/- coming from? Is…
Shredder
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Is the LM399 Temperature coefficient with the heater on or off?
The LM399 datasheet specifies a temperature coefficient "\$\Delta\$T/\$\Delta\$Temp". The conditions state an ambient range but don't specify if that's with or without the heater on.
Which is it?
user1816847
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2 answers
Solar Panel & Temperature coefficient of Voc Seems Exceedingly Low
I am reading over a solar panel data sheet and I'm having issue converting the Temperature coefficient of Voc as written because it seems exceedingly low to me. I fully understand the panel datasheet might be misleading as well but wanted to ensure…
user3128461
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