positive and negative temperature coefficient?

[electronics_kumar]

BOTH effect is belongs to same diode..how came the two effect zener and avalnche effect is having two different temperature coefficient..one is positive and other is positive temperature coefficient ?

 

[Miguel Gaspar]

The same occour in capacitors and some other devices.
And it reffers of how respond the device to changes in temperature and as you had discovered some times they are not equal.

 

[prasannavenkatesh krishna]

Positive Temperature Coefficient of resistance means the resistance of the material increases as the temperature of the material is increased.

Negative Temperature Coefficient of resistance means the resistance of the material desreases as the temperature of the material is increased.

Mostly semiconductors have negative temperature coefficient of resistance.

Regards,
prasanna