SG6520A Fairchild Semiconductor, SG6520A Datasheet - Page 8

• Manufacturer Part Number: SG6520A
• Description: The SG6520A is designed to provide the supply voltage, current supervisor, remote on/off (PSON), power-good (PGO) indicator, and fault protection (FPO) functions for switching power systems
• Manufacturer: Fairchild Semiconductor

© 2008 Fairchild Semiconductor Corporation
SG6520A • Rev. 1.0.3
Functional Description
The SG6520A provides over-current protection for the
3.3V, 5V, and two 12V rails. Whenever an OCP
condition occurs at any of the voltage rails, PGO is
LOW and FPO is open. The internal OCP comparators
have a very small offset voltage ( ± 3mV). The sink
currents of IS33, IS5, and IS12 are eight times the
current at the RI pin. The current at the RI pin is V
Here is an example demonstrating how to set the over
current protection. If I
R
the R
where C is bypass noise; suggested value is between
1µF ~ 2.2µF.
R
1
=5mΩ, R
2
=
2
I
I
1
RI
resistor is:
×
×
R
8
1
I
=
=30KΩ, and the OCP active level is 35A,
525
Ω
1
×R
1
> I
RI
×R2, OCP is active. If
RI
(1)
/R
I
.
8
Figure 5. OCP Set Up
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