ZHCSI27C April 2018 – October 2021 LM5036
PRODUCTION DATA
For applications where the input voltage exceeds 100-V, all of the 100V-rated internal circuit blocks, including VCC start-up regulator, auxiliary supply and half-bridge gate drivers, need to be bypassed, or powered from a reduced voltage. In this case, VIN pin can be powered from an external start-up regulator, as shown in Figure 8-4. If pre-biased start-up is required the integrated flybuck aux circuit should be used from the reduced VIN pin voltage to supply the secondary control circuit. If pre-biased start-up is not required, the bias supply VAUX1, can be derived from an external auxiliary supply. An external gate driver with higher voltage rating should be used to drive the half bridge.
Figure 8-4 External Start-Up Regulator