Is My Diode Becoming Too Hot? Troubleshooting Advice Needed

Click For Summary

Discussion Overview

The discussion revolves around the thermal performance of diodes used in a voltage regulation application. Participants explore whether the observed heating of a diode, reaching approximately 60 degrees Celsius, indicates a problem with the diode or the circuit design.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • Ramone expresses concern about the diode becoming warm to touch and questions whether this indicates a fault, noting the diode's specifications are unclear.
  • One participant suggests that diodes can tolerate significant heat and that if it conducts equally in both directions, it may be faulty, but emphasizes that the power dissipation depends on current and voltage.
  • Another participant provides a formula for calculating the maximum power dissipation in the diode based on the circuit configuration and suggests that excessive current may be the cause of overheating.
  • A different viewpoint is presented that using diodes for voltage regulation is not ideal, recommending fixed voltage regulator ICs as a better alternative.
  • One participant inquires about the specific application requiring the voltage limit, indicating a need for further context regarding the circuit's purpose.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether the heating of the diode is problematic. There are multiple viewpoints regarding the appropriateness of using diodes for voltage regulation and the implications of the observed temperature.

Contextual Notes

The discussion includes assumptions about the circuit design and the diode's specifications, which are not fully clarified. The potential impact of current levels and circuit configuration on diode heating remains unresolved.

ramonegumpert
Messages
187
Reaction score
0
Dear Experts,o:)

I have recently soldered some diodes to maintain a constant voltage. This i learned from this nice forum.

But when using it, the diode can become quite warm.

My doubt is, when diodes become warm to touch, like about 60 degrees celsius , is it something wrong with the diode?

I am not sure what kind of diode i am using but it has some aphabets and numbers on it which reads
"CT" and
"2 A 0 5"

I suspect it means 2 Amps diode.

The load does not drawing much current at about 162mA.

Someone told me that if your diode is hot, something is wrong.
I wonder is this true?


sincerely
Ramone :)
 
Engineering news on Phys.org
Diodes can stand more heat than your fingers can. If you can't hold it for more than 5 seconds, it is getting too hot.
If it stops being a diode and conducts equally in each direction, then it is faulty.

The power dissipated in a diode depends on the current and voltage. The voltage is about 1 volt for a diode carrying high current.
Yours isn't really carrying high current so it shouldn't get very hot.

Silicon diodes do get hot if they are carrying high frequency current. If this was the case, you might need Schottky diodes.
 
You seem to be describing a very simple shunt regulator and I assume you are using the diodes to provide bias for something.
If the circuit that you are using involves a resistor R from Vss in series with the diodes (forward biased), then the maximum power that the diode will dissipate is
Vd X (Vss - Vd)/R where R is the series resistor value. How much current does the circuit need? If the diodes are getting too hot, you may just be passing more current down this bias chain than is needed. Increase the pullup R value to something more sensible (if this circuit involves milliAmp circuit currents, then you don't need many mA down your bias chain) or use another biasing method - an emitter follower or something.
 
Using diodes for voltage regulation is a not a very good selection. You might consider using fixed voltage regulator IC's like 7805 (A 3-terminal device with 5 volts output), 7809 etc or LM17.
 
What is the specific application which requires this voltage limit?
 

Similar threads

SMPS transformer core getting hot advice
  • · Replies 48 ·
2
Replies
48
Views
10K
Programs In need of advice: How do I become a mathematician?
  • · Replies 43 ·
2
Replies
43
Views
8K
Transistor Switching for Driving LEDs - Expert Advice Needed
  • · Replies 8 ·
Replies
8
Views
5K
Admissions Need advice for my personal statement
  • · Replies 27 ·
Replies
27
Views
5K
Electrical Heating Problem with DIY A/C Electromagnet
  • · Replies 23 ·
Replies
23
Views
7K
Job Skills Overwhelmed by Choices: Seeking Advice on Staying Engaged with Project
  • · Replies 21 ·
Replies
21
Views
3K
Physics Badly Need Honest Advice to make an informed decision on my future in Physics
  • · Replies 17 ·
Replies
17
Views
4K
Graduate Why do tanks get hot when you fill them from higher pressure tanks?
  • · Replies 13 ·
Replies
13
Views
12K
Chemically regenerating my auto's catalytic converter?
  • · Replies 19 ·
Replies
19
Views
9K
High School Temperature of a black hole....observed from the singularity
  • · Replies 13 ·
Replies
13
Views
5K