LTM4631 Switching Regulator

Question

Hi, 
 We are using Switching Regulator IC PN# LTM4631IY#PBF to generate 1V output from 12V input. To get more output current, we are combining both the outputs (Paralleling output). I have few queries as follow-: 
 1) Can we keep pin-VOUT1S floating (as shown in below schematics) ? 
 If YES- Is resistor used in pin-VFB value (i.e-90.9k) correct? 
 If NO- then what can be the alternative connection and VFB resistor value? 
 2) Is the resistor used in pin-fset (i.e-165k) correct for 690Khz switching frequency? If NO- what can be the resistor value? 
 
 Kindly find the below schematics for review. 
 
 Thanks

ADIApproved · Accepted Answer

Hi Rashmita, 
 1. In parallel applications, VOUTS1 can be left floating as long as your VOUTS2 is connected to DIFFOUT. If your load is not close by and needs to use the differential remote sense amplifier, then don&rsquo;t connect VOUTS1 to VOUT1. 90.9k resistor for Rfb is correct since VOUTS1 is floating. 
 2. Using LTpowerCAD, 165k seems to be correct.)

Partner Forums

Partner Libraries

Products Mentioned

LTM4631 Switching Regulator

Thread Summary