ADDC02803SC/ADDC02805SA

REV. A

–9–

With regard to the range to which the output voltage can be

adjusted by the user, there are two concerns. As the output

voltage is raised it may become difficult to maintain regulation

at full power and low input voltage. As the output voltage is

lowered, it may become difficult to maintain regulation at mini-

mum power and high input line. In addition, if the output

voltage is reduced below 3 V, the secondary side control circuit

may not have a sufficient supply voltage to operate correctly.

Pin 4 (STATUS)

Pin 4 is active high referenced to –SENSE (Pin 1), indicating

that the output voltage is typically within

±5%. The pin is both

pulled up and down by internal circuitry. Figures 26, 27 and 28

show the typical source and sink capabilities of the status output.

Refer to the paragraphs describing Pin 3 (ADJUST) for effect

on status trip point.

3.00

2.25

1.50

0.4

1.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

2.75

2.50

2.00

1.75

Figure 26. Source Capability of Status Output

(ADDC02803SC)

4.2

3.8

2.2

0.8

2.6

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

3.4

3.0

2.6

Figure 27. Source Capability of Status Output

(ADDC02805SA)

1.0

0.8

0.0

1.0

19.0

4.0

7.0

10.0

13.0

16.0

0.6

0.4

0.2

Figure 28. Sink Capability of Status Output

Pin 5 is referenced to the input return and provides a semi-

regulated 13 V to 15 V dc voltage supply for miscellaneous

system use. The maximum permissible current draw is 5 mA

and the voltage varies with the output load of the converter as

shown in Figures 29 and 30.

OUTPUT CURRENT – A

15.0

14.5

13.0

022

2

4

6

8

10

12

14

16

18

20

14.0

13.5

(ADDC02805SA)

OUTPUT CURRENT – A

14.0

13.5

11.5

022

2

4

6

8

10

12

14

16

18

20

13.0

12.5

12.0

(ADDC02803SC)