Vo
VFB
KA431
Feedback Open
Loop
6V
PWM
3R
R
4.6V
56ms OLP
VDD Over-Voltage Protection (OVP)
VDD over-voltage protection prevents IC damage caused
by over voltage on the VDD pin. The OVP is triggered
when VDD voltage reaches 28V. Debounce time (typically
130µs) prevents false trigger by switching noise.
Over-Temperature Protection (OTP)
The SenseFET and the control IC are integrated,
making it easier to detect the temperature of the
SenseFET. When the temperature exceeds
approximately 142°C, thermal shutdown is activated.
Figure 34. OLP Operation
© 2009 Fairchild Semiconductor Corporation
FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3
14
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