LTC3265

Hello

We are using LTC3265 DHC Package for driving power rails of ADI's AD8139. 

- The AD8139 is configured for I-V differential converter with supply rails of (+/-5.6V Approx)

- LTC3265 is configured as follows (ref typical application circuit pg 16/20  of datasheet): 

VIN_P = 5;  RT= 0; 

R1 = 36.5k, R2 = 10k 

VLDO+/- = +/- 5.6 V (approx)

Additionally, we have provided 20pF cap across LDO and ADJ for both LDOs. 

The VLDO+/- measurements are as expected.  

However, the input supply current (80 mA) of LTC3265 is approximately twice the current demanded by AD8139 i.e 42 mA, as no input single is applied.  We verified this value by powering  AD8139 directly from Power supply (21 mA each supply rail) and then from LTC3265. Is this behavior true for LTC3265 ?.  Plz help us in this regard. Thanking in anticipation. 



moved and added tag
[edited by: elizabeth.uva at 2:13 PM (GMT -4) on 27 Apr 2021]