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==== TCR (Temperature Coefficient of Resistance) ====
 * The parts should be chosen so that the TCR doesn't produce too much change in the heater current.
 * Maybe its not much of a big deal since we have a temperature sensor for the feedback, but in some cases this circuit could be used as an open loop heater.
 * [[http://vishaypg.com/docs/63609/63609.pdf | Vishay Precision]] has some metal foil resistors with 0.2 ppm/C. The best from anyone else is 2 ppm/C. Most resistors are more like 20-200 ppm/C.
  • DC Current source

  • Max current > 1 A

  • Takes unfiltered DAC signal as input (differential)
  • LED power indicators
  • Heater power unregulated (but filtered?)
  • Regulators inside for the opamps

  1. Rana links to new design from Analog Devices

  2. Kira's Overview sketch

TCR (Temperature Coefficient of Resistance)

  • The parts should be chosen so that the TCR doesn't produce too much change in the heater current.
  • Maybe its not much of a big deal since we have a temperature sensor for the feedback, but in some cases this circuit could be used as an open loop heater.

  • Vishay Precision has some metal foil resistors with 0.2 ppm/C. The best from anyone else is 2 ppm/C. Most resistors are more like 20-200 ppm/C.

Electronics/HeaterDriver (last edited 2018-07-31 18:22:56 by RanaadhikariATligoDOTorg)