LTC3779 modes of operation

Question

For the LTC3779, 
 
 1) Does or can the chip automatically go into continuous mode of operation once the load current demand is high enough? The problem is that in forced continuous mode, no load, the inductor gets very hot. 
 2) If we then set the chip to be in pulse skip mode, does it stay in pulse skip mode even when a large load current is turned on? 
 3) If the chip does not automatically do this, then is there a recommended way to make this switch automatically 
 as a function of load current? 
 4) Also, what is the required common mode range of voltages for the proper use of IAVGSNSP and IAVGNSN differential current sense pins? 
 
 Thank you

FormerMember · Accepted Answer

gwongLL said: 1) Does or can the chip automatically go into continuous mode of operation once the load current demand is high enough? The problem is that in forced continuous mode, no load, the inductor gets very hot. 
 During FCM, it is always on continuous mode. 
 gwongLL said: 2) If we then set the chip to be in pulse skip mode, does it stay in pulse skip mode even when a large load current is turned on? 
 The switching modes is only during light load operations. It will operate on continuous conduction mode when the load current is high enough. 
 gwongLL said: 3) If the chip does not automatically do this, then is there a recommended way to make this switch automatically 
 as a function of load current? 
 Read no.2 answer. Thank you. 
 gwongLL said: 4) Also, what is the required common mode range of voltages for the proper use of IAVGSNSP and IAVGNSN differential current sense pins? 
 
 Please read datasheet applications information to help you design your circuit. Refer below snip, it is located on page 21.)

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LTC3779 modes of operation