Hey all,
It's my first question on this platform and I hope somebody can help me with my problem. I have connected the LTC3890 with the LTC4000 to charge 4 Li-ion batteries. Before connecting the ITH pin both boards worked good. The ITH on the LTC3890 is 0.535 V and the Vout is 16,8V. When i connected the pin ITH between the charger and the converter, the pin ITH dropped to 0.4V. As result the Vout of the converter dropped from 16.8V to 12.5V. I have checked all the Amplifiers which effect the pin ITH in the LTC4000 but non of it have reached its maximal value. I am using the evaluation kits of both of the components (DC1830A-B for the LTC4000 and DC2236A-B for the LTC3890). IN the datasheet of the LTC4000 page 23 i have read the next: 
How can I make the pin ITH in the LTC4000 goes to 0.535 V to reach the needed Vout of the LTC3890?
Thank you in advance 
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