Other Parts Discussed in Thread: LM4051-N
Hi sir,
I'm looking for a constant current source with the following properties:
- output current ideally in the 50mA range, but 10mA could work too
- the precision doesn't matter so much (100ppm is plenty), but it's more important for the current to be stable over temperature
- operational temperature up to 125C
The application is in-circuit temperature sensing by measuring changes to the resistance of copper. The current source drives some long, intentional copper traces and we measure the voltage across the long trace.
I'm looking for something that can deliver a relatively stable current over a wide temperature range.
The LM134 has an output current drift of 0.3%/C, or equivalently 3000ppm/C.
I'm interested in something that's closer to the 3 or 30ppm/C range, so that the total fluctuation between 25C and 125C is ~3000ppm.
Thank u.
Regards,