I am using AD5726. On the datasheet there is reference input current (pag.3), for VREFN there is written -1mA (max).My question is: should I consider 1mA going inside the chip or 1mA coming from the chip ? What does minus means ?Thanks.Lucio
From the part's point of view, if the input current is negative then the current is coming from the part. This would make sense if the pin (i.e. AVSS) is below 0V.
VREFN is -2.5V, AVSS is -6V. So should I consider input current from VREFN pin coming from the part going to AVSS through, for example, an external resistor ?
I am new in this community, should I consider this as an Analog Devices' official answer ?
Thanks, best regards,
I would also like to ask: what does it appen if VREFP - VERFN < 2.5 V ?
On the datasheet it says it must be at least 2.5V, but my shunt voltage reference is 2.5V with initial tolerance of 20mV. Is it an issue ?
I don't understand your question. Do you mean that your VREFN pin is connected to the AVSS through an external resistor? If so, then the current will flow from the VREFN pin to the AVSS given that VREFN = -2.5V and AVSS is 6V.
As stated in the data sheet, a minimum of 2.5V should be observed between VREFP and VREFN for the accuracy of the part. Anything lower than this may cause inaccuracy of the part.
Yes, I stand corrected. it's -6V.