Finding the forward current of diode

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SUMMARY

The discussion centers on calculating the forward current of a silicon diode using the Shockley diode equation. Given a forward current of 1 mA at a voltage of 0.9 V and a thermal voltage (nVT) of 26 mV, the forward current at a voltage of 1 V is determined to be 46.81 mA. The user initially struggled with the calculation but resolved the issue by identifying input errors in their calculator. The Shockley diode equation used is Id = Is exp(Vd/nVT).

PREREQUISITES
  • Understanding of the Shockley diode equation
  • Knowledge of silicon diode characteristics
  • Familiarity with thermal voltage (nVT) calculations
  • Basic proficiency in using scientific calculators for exponential functions
NEXT STEPS
  • Study the derivation and applications of the Shockley diode equation
  • Explore the effects of temperature on diode performance
  • Learn about different diode types and their forward current characteristics
  • Investigate methods for accurately using scientific calculators in electrical engineering calculations
USEFUL FOR

Electrical engineering students, hobbyists working with diodes, and professionals involved in semiconductor device analysis will benefit from this discussion.

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Homework Statement


A Si diode is operated at the room temperature (27 °C). For a forward current of 1 mA, the voltage VD is found to be 0.9 V. If the VD is 1 V, the forward current = _____ mA. Given that nVT = 26 mV

The answer is 46.81

Homework Equations


Shockley diode equation?

The Attempt at a Solution


I tried to use the shockley diode equation, Id=Is exp(Vd/nVt)
I subbed in values 0.9V and 1mA into eqn to get Is and then using newfound Is to sub into shockley diode eqn again with Vd 1V now. However, I didn't get the answer 46.81mA.

Is there an assumption that I have made wrong? Any help in figuring my mistake out is greatly appreciated. Thank you so much!
 
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Please show your working so we can check it.
 
NascentOxygen said:
Please show your working so we can check it.
Oh my gosh, as soon as I was typing out my steps and I finally got the answer. Must have keyed in wrong values somewhere in the calculator previously.
So sorry for the trouble but thank you!
 

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