LTC6813-1 Vref2 Maximum Current Out

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!