Question: TCR (Temperature coefficient of resistance)
0

Mumbai University > Electronics Engineering > Sem 8 > MEMS Technology

Marks: 3M

ADD COMMENTlink
modified 2.9 years ago by gravatar for Juilee Juilee2.3k written 2.9 years ago by gravatar for Hetal Gosavi Hetal Gosavi70
0
  • Resistance values for conductors at any temperature other than the standard temperature on a specific resistance must be determined by the formula

    R= Rref[1+α(T-Tref]

    Where,

    R= conductor resistance at temperature T

    Rref= conductor resistance at reference temperature Tref

    .α= temperature coefficient of resistance TCR for conductor material

    T= Conductor temperature in degrees

    Tref= reference temperature that is specified for conductor material

  • The TCR symbolizes the resistance change factor per degree of temperature change
  • All materials have specific resistance and changes according to the temperature
  • For pure metal the TCR is positive, ie the resistance increases with increase in temperature
  • decreases with increase in temperature
  • For alloys the TCR is zero ie the resistance hardly changes at all with variation in temperature.
  • In any material the internal resistance will change as the temperature changes.
  • The rate of resistance change is based on temperature and is referred to as TCR.
  • It is denoted in units of Ppm/C and determined from the resistance changed from some reference temperature and change in temperature
  • One advantage of poly Si over Cryst. Si is its reduced TCR
  • The TCR for Poly Si and crystal is approx 0.04%/degree C. compare to 0.14%/degree C for Cryst. Si.
  • The deposition process and type of dopant can alter the sign of TCR
  • Emitter type Poly si have a TCR of -0.045%/degree C
  • Resistance with positive TCR are used in compensating the –ve temp dependence of piezoresistance sensor.
ADD COMMENTlink
written 2.9 years ago by gravatar for Hetal Gosavi Hetal Gosavi70
Please log in to add an answer.