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 2006 Semtech Corp.

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SC4602A/B

POWER MANAGEMENT

Typical Characteristic

Over current protection characteristic of SC4602B 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 SC4602B 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 conditio

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