We use an ADR430B as the external reference. This device has an external trim adjust pin. The datasheet shows how to connect this to a pot for adjustment. We have been considering some possible circuits which would measure the temperature and then adjust this trim node to compensate. To do this, we would need additional information on the trim input. Regarding the trim pin, could you please tell us:
Can we drive the the pin with an opamp from a DAC?
Is it a voltage or a current input?
What is the input range?
What is the input impedance?
When we move the potentiometer to a higher voltage, does the ouput voltage of the ADR430B go up or down?
Is there an equation which relates the ouput voltage to the voltage or resistnace at the trim pin?
Thanks and Best Regards,
-Tim Starr on behalf of RD@AT