Post Go back to editing

LTC4412- Power supply Switching delay

Hello ,

   We are planning to implement a power path controller using the below circuit. 

  We need to know the tome delay between the assertion of ctrl pin and the gate and stat pin outputs when the powwr supply is switched from primary to auxillary.

  We need the above timing delay to make sure that the load voltage will not drop very much and the system will be stable. 

 Peak current load of our system is 1A .  Please advise us the capacitor needed at the output voltage side. 

Note: we are planning to use DMP6110SFDF-13 P-MOSFET from diodes incorporated. 

Parents
  • Hello,  If V1 is your primary supply and V2 is auxiliary: When you toggle CTL to switch off GATE, note that the output will fall only till M1 turns on or M1 body diode catches output a diode below V2. Therefore, output should never fall below V2 - 0.7V (even if M2/M3 are on). Even otherwise, it is best to use LTspice to estimate the switchover characteristic since transition time will depend more on FET and load capacitances and load current than CTL propagation delay.

Reply
  • Hello,  If V1 is your primary supply and V2 is auxiliary: When you toggle CTL to switch off GATE, note that the output will fall only till M1 turns on or M1 body diode catches output a diode below V2. Therefore, output should never fall below V2 - 0.7V (even if M2/M3 are on). Even otherwise, it is best to use LTspice to estimate the switchover characteristic since transition time will depend more on FET and load capacitances and load current than CTL propagation delay.

Children