Dear Friends,
Does anyone know what is the maximum current capability of the Vref2 pin of the LTC6813-1 Chip, I'll need to attach 18 NTC temperature sensors to measure the 18 cell's temperature individually. according to the following way I decide to fulfil that my requirement. But I have dubbed with the Vref2 current is sufficient to attach three NTC sensors parallel ways. In the data sheet there is no any information about the Vref2 maximum current out rate. any suggestion is appreciated.
Thank you!
Hi randikajdpmco,
As per datasheet the absolute maximum rating of this pin is 10mA.
Please Refer to the following graph to decide Vref2 current you want to draw.
Dear Sgarg,Thank you so much for pointing this graph. Actually, I thought the 10mA only for reference point on the graph. According to my setup the current consumption would be around 450uA.
So as to referencing the data-sheet graph, the Vref2 deviation could be calculated as following way.When Vref2 load current 450uA, the Vref2 deviation would be around -200ppm.Then Vref2 @ 450uA load,
Vref2 = 3 - (3 x(200/10^6))
=2.9994VConclusion, this setup would be pretty safe.Cheers!