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SC4601

POWER MANAGEMENT

Over current protection characteristic of SC4601 for 3.3V to1.5V @6A application:

The over current protection curve below is obtained by applying a gradually increased load while the load current

and the output voltage are monitored and measured. When the load current is increased from 0 to 9A (over current

trigger point), the output voltage is 1.5V, corresponding from Point A to Point B. As the load current increases

further from 9A to 9.6A, the output voltage drops significantly from 1.5V (Point B) to 0.54V (Point C). Because an

over current and a lower output voltage (0.54V < 68.75%*1.5V = 1.03V) are present at Point C, the SC4601

enters its HICCUP mode. Then the locus of the output current and the output voltage follows Line CD as shown in

the curve. Due to the over current applied, the HICCUP protection will go back and forth on Line CD. This prevents

excess power dissipation in the P-MOSFET during a short output condition.

Typical Characteristic (Cont.)

Overcurrent protection

0

0.5

1

1.5

2

2.5

3

0

3

6

9

12

15

18

Output Current (A)

B

C

D

A