Resistor on the DCIN pin of the LTC4011

Question

Hi, 
 The datasheet recommendation is 20 k&Omega;, but as I want to reduce power consumption as much as possible, I would like to increase the resistance value or use without the resistor. 
 Is there a formula for calculating the resistor value? 
 How high can the resistance value be increased? 
 Regards, 
 Kazu

ADIApproved · Accepted Answer

Hello Kazu, 
 The purpose of this resistor is for a stable sensing of voltage across the DCIN pin. I recommend having this resistor so that the sensed voltage is with respect to the GND and not just floating. 
 Regards, 
 Nino)

ADIApproved · Answer

Hello Kazu, 
 The 20kOhm value is the recommended value for the typical applications and demo board. This 20kOhm is suitable for driving the DCIN pin above Vcc. You may vary this resistor as long as you can drive this pin above Vcc. Also, observe the operating voltage capability. 
 Regards, 
 Nino

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Resistor on the DCIN pin of the LTC4011