??? 05/02/05 20:50 Read: times |
#92759 - Track the drift Responding to: ???'s previous message |
Prahlad J. Purohit said:
What are these components that track each others drift. I couldnt get exactly what you mean. Please elaborate a bit more on this. Prahlad Purohit Think, as an example, of resistors in a Wheatstone bridge. You'll like all of them have *the same* temperature coefficient and be at the same temperature all the time so the changes in temp get cancelled in the final result. Analyze the bridge with Rx(1+DeltaTempx) with a different DeltaTempx for each resistor (x=1..4) so you can get a general equation, and then make all DeltaTempx equal. You'll get the DeltaTemp cancelled which means the circuit behavior doesn't depend on temperature. Another example: in circuits with transistors, the base-emitter junction always has a TempCo of (approx.) -0.6mV/degree. This property can be useful to measure temp, but in another applications could led to big drifts. So you can employ another transistor as P-N diode, best if gotten from the same batch, and change the resistor polarizing network to countermeasure the tempco of your main transistor. I don't know it I made it clear... Regards. Enrique. |
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Tracking the offset. | 01/01/70 00:00 | |
re:drift | 01/01/70 00:00 | |
Drift compentsation | 01/01/70 00:00 | |
Track the drift | 01/01/70 00:00 | |
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