Datasheet BCR601 (Infineon) - 8

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BCR601 hot plug IC with voltage feedback to primary side Thermal characteristics 3 Thermal characteristics Figure 7 Maximum permitted effective output source current out of pin DRV into external driver transistor for a design example of 4 mA DC driver
The maximum permitted effective driver source current shown in
Figure 7
can be calculated by following equation: TOTP,min − TA V I − V S OPTO R S ⋅ IS − 2 ⋅ 2 T I I thJA OTP, min − T A OPTO DRV = V = − IS − S VS ⋅ RthJA 4 The equation considers the power dissipation caused by current consumption of the IC itself and the optocoupler current. If driver current exceeds the calculated threshold the lower specified limit of the overtemperature protection will be exceeded and OTP might be triggered. TOTP,on, min The lower spec limit of the overtemperature protection threshold should not be exceeded to avoid triggering the OTP. IOPTO The maximum optocoupler sink current into pin OPTO when IC fully turns on the current sink. Besides the spec limits of BCR601 the maximum current is also limited by the optocoupler supply voltage and external pull-up resistor. Datasheet 8 Revision 1.1 2018-12-3 Document Outline Features Protection features Target applications Advantages with respect to discrete solutions Product validation Device information Description Table of contents 1 Pin configuration 2 Functional description 3 Thermal characteristics 4 Absolute maximum ratings 5 Operating conditions 6 Electrical characteristics 7 Package information 8 References Revision history Disclaimer