Temperature is a property of a substance related to the amount of heat energy it contains.

learn more… | top users | synonyms

0
votes
0answers
13 views

LM35DZ Negative Output

I'm having a bit of an issue with what will probably turn out to be something trivial. I'm trying to interface a temperature sensor with a Raspberry Pi 2 - there are lots of examples around the web. I'...
1
vote
2answers
127 views

Why does the regulated voltage go down?

I have designed this simple analog temperature transmitter. Specifically, this is a 2-wires loop-powered transmitter. The circuit is intended to measure temperatures from -50 to 400 °C. The first ...
1
vote
1answer
63 views

How does this temperature alarm circuit work

Casn you please help me understand how this temperature alarm circuit works? I am a bit over my head here, but I would very much like to understand this. If you would like to look at the multisim ...
2
votes
0answers
46 views

Why does my SEPIC converter output more power at higher temperatures? What are the implications of this behavior?

I have a Pololu S18V20ALV SEPIC voltage regulator board that is wired to a high-amperage 5V USB power source on the input and a DC brushless fan on the output. The output is set to about 5.5V. ...
0
votes
2answers
77 views

AT-Mega 2560 analog pins

I am trying to measure the temperature from four MCP9700AE temperature sensors (http://www.digikey.ca/product-detail/en/microchip-technology/MCP9700A-E-TO/MCP9700A-E-TO-ND/1212508) using an ATMega ...
1
vote
0answers
28 views

MAXIM31855T thermocouple chip, is there a through hole equivalent that works on the spi bus, having problems with SMD routing

I need to produce a circuit board to measure 16 temperatures from different thermocouples of types J and T, Maxim has the perfect chip, the MAX31855(T,J), the only problem is that it is surface mount ...
4
votes
2answers
190 views

what is the tempreture at which the thermal limit of an amplifier is reached

Introduction: I am upgrading a "power amplifier" that a fellow engineer has designed , my job is to add thermal protection against failure in prolonged use (or operator miss use). The package of ...
0
votes
1answer
67 views

How many DS18B20 temperature sensors can I connect to one bus arduino?

How many temperature sensors can I connect to one bus without losing accuracy.Can I use for example 50 sensors to one bus? Should I change the resistor when I connect too many sensors? Here is the ...
0
votes
2answers
89 views

Does a colder CPU perform better?

Are there any perks in keeping a CPU at a low temperature; between 0 and 20 degrees Celsius in particular? In particular, does it produce less errors in computation and therefore slightly improved ...
4
votes
1answer
102 views

How to estimate the required PCB surface area for SMD power resistors

I am migrating a design from through-hole parts to use as many SMT devices as possible. There are 7- 2 Watt power resistors in the current design. These are metal-oxide resistors that have crimped ...
3
votes
4answers
256 views

I need the full range from an LM34DZ, but I don't have an 1N914 diode. Is there a replacement?

I want to read the full range on my LM34DZ, but I can't seem to find any 1N914 diodes. Is there anything I can replace it with?
32
votes
10answers
5k views

Why is the temperature range of industrial and military products so high?

From Wikipedia the common temperature range for electrical components is: Commercial: 0 to 70 °C Industrial: -40 to 85 °C Military: -55 to 125 °C I can understand the lower part (-40°C and -55°C) ...
1
vote
4answers
95 views

Do consumer high temperature RF ASICS exist at 200C?

So at lunch I was browsing Indiegogo projects and I saw this one here It's a wireless meat thermometer, I've seen it in some permutation or another a few times on sites like this. Apparently no one ...
5
votes
3answers
362 views

What is the main source of variation between thermocouples of the same type

Thermocouples have stated tolerances [wikipedia]. However, the characteristic behaviour is defined by the materials in contact, so there aren't size or shape considerations as for RTDs. What are the ...
0
votes
4answers
60 views

Tap into 4 wire RTD

Is there any way to tap into an existing 4 wire RTD without changing the resistance, and therefore changing the temp that the existing device will read? Here's the scenario. The device is a medical ...
0
votes
2answers
59 views

Understanding Thermal Stability and Drift in Linear Regulators

I'm considering 3-terminal linear regulators (LM317, LM350, TL783, etc.) for a power supply that regulates a 150V wobbly DC voltage down to 145V or 140V. My load is like 30-65mA. So, depending on ...
0
votes
2answers
47 views

Schmitt Trigger does not go to ground

i would like to create simple circuit to drive an computer fan (12V, 0.5A) is the temperature is above 42 celsius and stop when the temperature decreased below 36 celsius. I am simulating in LTSpice. ...
1
vote
1answer
41 views

Temperature calibration for of the shelf sensor nodes

Terminology: sensor node sensor I have been experimenting with of the shelf temperature sensor nodes. The exact device in question is an Aeon Labs LLC, Aeontec Z-Wave MultiSensor 6. I got the ...
6
votes
4answers
207 views

Can any BJT be used for temperature sensing?

I'm looking for a cheap and easy way to monitor temperatures and came across the Microchip EMC1403 which interfaces to general purpose diodes (or transistors with their base tied to collector/emitter ...
0
votes
2answers
71 views

Ways to accurately heat up SMD component(s) on a PCB to a specific temperature?h

I need to calibrate temperature sensors (ADT7481). My DMM can measure temperature with a thermocouple. And I expect it to be reasonably accurate (within ~1.0 Celsius degree). Question at large ...
0
votes
0answers
35 views

Estimate kanthal's temperature by power dissipation

I've a bare Kanthal A-1 wire, And I want to Estimate it's temperature, basically to make a °C vs W plot. In this post Thermal resistance is used to do it as: ...
0
votes
1answer
77 views

How to measure the temperature of a fridge with arduino?

A want to make a system with arduino to measure the temperature of many fridges and send SMS if temperature is over limits. I am wondering how to measure digital temperature without putting wire ...
0
votes
0answers
33 views

Arduino input noise control

I have been working on a project to simulate a fire suppression system. Below is a brief theoretical picture of what the project looks like Anyhow, the system is set up into a box, and the system ...
0
votes
0answers
33 views

Nexys4DDR temperature sensor reading code error

I am trying to read the temperature sensor on my Nexys4DDR board using i2c protocol. My code is outputting all of the leds as 1, thus giving me the default value. Where am I going wrong? ...
0
votes
1answer
16 views

Lower Power Inductive Heating Circuit Design Questions

I'm trying to design a very low power (<=10W) inductive heating circuit that will heat the work material to 40-50degC. I've seen plenty of Royer Oscillator circuits online (see here: http://www....
1
vote
1answer
47 views

ferronickel temperature coefficient

I'm heating a ferronickel wire, and I need a reliable measurement of temperature, I was using a thermocouple to do this measurement but the wire is cooled when it's touched by the thermocouple so now ...
0
votes
1answer
24 views

Marlin temperature update frequency 3Dprinter

I would like to know at what frequency is the temperature information pulled by the marlin software. I have looked into the code but it insn't obvious to me.
3
votes
1answer
71 views

Reasons to use an analog temperature sensor instead of a digital one

I'm designing a microcontroller-based system that includes a thermostat. When choosing which temperature sensor to use, I noticed that analog ones have more or less the same power consumption, the ...
0
votes
1answer
77 views

Why we put 10Kohm resistor in parallel with 144Kohm that exist inside USB-6008? [closed]

By using LM35 Temperature sensor and USB-6008 a 10Kohm resistor is placed between GND and AI0 and connected to LM35 with a wire to GND and Vout respectively. By refer to Analog Input circuitry in ...
1
vote
2answers
82 views

How to maximize microcontroller temperature?

I need to test how hot a specific microcontroller can get in different situations. The goal is to have the microcontroller heat up as much as possible just by using it. I was thinking I'd need to ...
0
votes
1answer
27 views

Sensor Performance Analysis

I've recently built a temperature sensor and have been testing it against a reference thermometer in several different scenarios/environments/temperature ranges. My question is, how do I analyse my ...
5
votes
6answers
1k views

Measure temperature on a moving engine valve: transfer voltage and reading wireless?

I am an automotive engineer with very very little or almost zero electrical/electronics experience. I am working on logging real time temperature values on an engine exhaust valve and mounting a ...
1
vote
2answers
102 views

What resistor values should I use for a voltage divider that has to operate at low temperatures?

I'm designing a flight computer for a lightweight pico balloon - it will (hopefully) operate in the upper atmosphere down to around -40C. To keep the weight down, the whole thing is going to be ...
6
votes
1answer
104 views

How to change the temperature of sub-circuits in LTSPICE

I have subcircuits of a solar cell (resistors and diodes) in LTSPICE. I want to connect the solar cells (sub-circuits) together. However, each solar cell has a different temperature. I can set the ...
0
votes
0answers
21 views

Orcad PSPICE Temperature Sweep

I have built a multivibrator oscillator using an op amp circuit (similar to a 555 timer approach) in PSPICE. The output is correct so the entire circuit is functionally working. I am trying to see ...
0
votes
1answer
68 views

Simulating a Constant Temperature Anemometer

I am trying to simulate the results I see when using a constant temperature anemometer circuit to sense air flow. An excellent discussion can be found: arduino thermal anemometer. Here is my ...
3
votes
1answer
199 views

Circuit reliability, especially tin solder, under wide temperature range -40 degree to +85 degree

We are trying to have our Lab product work in industry environment. One key factor we are thinking about is the operating temperature, since we have never done any environment test before. Our ...
-2
votes
2answers
76 views

Voltage regulator current and heating

Many texts I read take (Vin - Vout)*Iload i.e the current Iload is I3 in the below figure when calculating temperature of a regulator: But I3 is not exactly same with I1 there is something called "...
0
votes
0answers
42 views

Measuring the temperature of copper wire

I'm doing an experiment with copper wire, and I need to be able to measure the temperature of the wire. I've looked into temperature sensors and infrared thermometers, but I'm not sure how to ...
1
vote
2answers
49 views

MAX7221 experiencing 40C temperature rise above ambient

Each MAX7221 (2) in my current design is getting very hot. I used the FLIR One to get a general measurement. I observed a 40C rise above ambient. I'm not sure what the root cause is. Perhaps ...
1
vote
1answer
23 views

When using conventional means to control a heating element, how does it affect the peak required VA?

This question is similar to two others, here and here, but with a small difference. To allow a bit of context: Suppose I have a winters day with lots of sunshine. I have an off-grid PV system, and ...
1
vote
2answers
116 views

Atmels AtSAM3s gets a bit warm running a test code on my dev board. Is there a problem?

I have a dev board developed by myself. I was using At91SAM7S256 but now I'm migrating to it's successor ATSAM3S8B. The MCU on the dev board for SAM3S gets warm. I am searching for someone with ...
3
votes
2answers
192 views

Micro-controller failure problem as the temperature raises

I'm using at91sam3s8b(cortex-M3) for my project.The hardware board connects to PC using USB port. The firmware contains some cryptographic algorithms (it includes shifts, Xors, memory substitution ...
0
votes
3answers
150 views

MOSFET Drain-to-Source Leakage Current over voltage and temperature

I'd like to know what's the characteristic curve of Idss in N-Channel MOSFET transistors over different Vds values at high temperature. As I've checked datasheets (like Fairchild's 2N7000 or FDC637BNZ)...
0
votes
1answer
471 views

AD620 in Proteus: timestep too small

I've made this circuit in Proteus, as a part of a practice report: In real life it works, as I built and tested it. But in Proteus, when I want to run the simulation, I get these errors: ...
0
votes
0answers
74 views

LM35 and OA741 to measure temperature

I am following this tutorial. http://8051funkey.blogspot.com/2014/08/temperature-sensor-using-741-opamp-lm35.html?m=1 It isn't quite working. My circuit always show the red light. My question is how ...
-2
votes
1answer
72 views

What is an acceptable temperature rise for a Mosfet?

I will be using driving N-channel Mosfets with 5v PWM to switch 24v 2A(per channel) LED strips. I will use four per strip (RGBW) and have 6 strips, totalling 24 Mosfets on the PCB. I am looking at ...
11
votes
5answers
2k views

Electronics in high temperature - operating 30 mins - 2 hours, up to 500 °F - possible?

Would electronics survive if the ambient temperature of the environment was between 120 °C (250 °F) and 260 °C (500 °F) and the operating time was between 30 minutes and 2 ...
2
votes
4answers
118 views

What is more accurate, thermistor's R-T table or Steinhart-Hart equation?

If I want the conversion of thermistor's resistance to temperature to be as accurate as possible, should I refer to a table or use the Steinhart-Hart Equation? I am in doubt because a table contains ...
1
vote
2answers
63 views

How to determine temperature with LSM303DLHC

I am using a LSM303DLHC and am very confident I have the I2C communication working well. I am now trying to use the devices 12 bit temperature sensor. The datasheet is not clear and the tech ...