# BIASING

#### koley

Joined Mar 3, 2006
1
Could someone kindly help me with this assignment.

The diode current, i terms of voltaveV, is approximately given by
I=I.{exp(eV/kT)-1} where e=1.6^-19 coulomb is the electronic charge, k=1.38^-23joule k=boltzmann constant and T-temp. in K
if the saturation current I. is 1ηA, cal the forward and reverse resistances at V=0.2 and T=300K[/FONT]

Thanks a lot.

#### Papabravo

Joined Feb 24, 2006
20,369
Originally posted by koley@Mar 4 2006, 12:10 AM
Could someone kindly help me with this assignment.
The diode current, i terms of voltaveV, is approximately given by
I=I.{exp(eV/kT)-1} where e=1.6^-19 coulomb is the electronic charge, k=1.38^-23joule k=boltzmann constant and T-temp. in K
if the saturation current I. is 1ηA, cal the forward and reverse resistances at V=0.2 and T=300K[/FONT]

Thanks a lot.
[post=14623]Quoted post[/post]​
I'm going to assume that V(reverse) = -V(forward) = -0.2 Volts

So
R(forward) = V(forward)/I(forward) = +0.2/I(forward)
R(reverse) = V(reverse)/I(reverse) = -0.2/I(reverse)

does that help?

By the way is this a germanium diode?

#### windoze killa

Joined Feb 23, 2006
605
Originally posted by Papabravo@Mar 4 2006, 03:32 PM

By the way is this a germanium diode?
[post=14624]Quoted post[/post]​
Aren't germanium diodes dead and buried and pushing up daisies?????

Or should that be pushing up geraniums?????

Just some sick humour. Please forgive me and even ignore me.

Sorry. Couldn't resist.

#### Papabravo

Joined Feb 24, 2006
20,369
Originally posted by windoze killa@Mar 4 2006, 02:47 AM
Aren't germanium diodes dead and buried and pushing up daisies?????

Or should that be pushing up geraniums?????

Just some sick humour. Please forgive me and even ignore me.

Sorry. Couldn't resist.
[post=14631]Quoted post[/post]​
Apparently not
Germanium Diodes

#### beenthere

Joined Apr 20, 2004
15,819
Hi,

Just bought some 1N34's - you just never know when they'll come in handy. Might even save an oatmeal box and wind a coil some day.

#### aac

Joined Jun 13, 2005
35
Originally posted by koley@Mar 3 2006, 11:10 PM
Could someone kindly help me with this assignment.
The diode current, i terms of voltaveV, is approximately given by
I=I.{exp(eV/kT)-1} where e=1.6^-19 coulomb is the electronic charge, k=1.38^-23joule k=boltzmann constant and T-temp. in K
if the saturation current I. is 1ηA, cal the forward and reverse resistances at V=0.2 and T=300K[/FONT]

Thanks a lot.
[post=14623]Quoted post[/post]​
The small signal equivalent conductance can be found by taking the derivative of the current equation with respect to V.

dI.{exp(eV/kT)-1}/dV = I.{exp(eV/kT)}*(e/kT)

Just put .2 and -.2 in calculate the conductance and divide into 1 to get resistance.