Post Go back to editing

LT8210 Burn out the mosfet

Category: Software
Product Number: lt8210

Dear ADI:

    I use lt8210 for buck boost charger for battery , But now I use 2.5mΩ RSENSE series to inductor for sample inductor current , And my inductor saturation current about 30A , When input is 39V, output is 54.7V, LT8210 work in boost state and CCM mode ,Then the MOSFET A  and C  is burn out , Maybe Overcurrent  and inductor saturation, But i Check the datasheet page 5 about "Cycle-by-Cycle Inductor Current Limiting" ,The give message is that "VSNSP1 – VSNSN1 = 50mV"  If 50mV is correct , When I use 2.5mΩ Rsense , The Maximum current  just only 20A , I wanna know the VSNSP1 – VSNSN1= 50mV is right or not ,TKS!

Parents Reply Children
  • Dear Chris:

        First burn out mosfet and LT8210 Chips, Mainly problem is GATVCC is untabilty, If load over 0.5-0.6A , GATVCC output voltage is unstable and the SW1 and SW2 ringing is very serious like a wave, I try to add capacitor to GATVCC pins from 10uF to 20uF, Never change the impact,Maybe GATVCC Insufficient driving ability To 40mA, Or other problem, Or VC loop compensation ????

  • Dear Chris,

    We're using LT8210 to drive 450W load. This chip works in Boost, Pass-Thru and Buck topologies as configured by Mode pins.

    Recently  asked about loop compensation that could be root cause of the MOSFETs abnormal operation and as a result their burning. Unfortunately, the datasheet of this chip doesn't explain in detail how to calculate the values of RCx and CCx. It'd be useful to know how the values of RCx and CCx depicted in DC2814A-A,B and C were found