ADP3303

–8–

REV. A

OUTLINE DIMENSIONS

Dimensions shown in inches and (mm).

8-Lead Small Outline IC

(SO-8)

0.1968 (5.00)

0.1890 (4.80)

8

5

4

1

0.2440 (6.20)

0.2284 (5.80)

PIN 1

0.1574 (4.00)

0.1497 (3.80)

0.0688 (1.75)

0.0532 (1.35)

SEATING

PLANE

0.0098 (0.25)

0.0040 (0.10)

0.0192 (0.49)

0.0138 (0.35)

0.0500

(1.27)

BSC

0.0098 (0.25)

0.0075 (0.19)

0.0500 (1.27)

0.0160 (0.41)

8

°

0

°

0.0196 (0.50)

0.0099 (0.25)

x 45

°

ADP3303-5.0

OUT

IN

GND

OUTPUT SELECT

5V

0V

C1

1.0 F

ADP3303-3.3

OUT

IN

GND

C2

0.47 F

SD

SD

Figure 23. Crossover Switch

Higher Output Current

The ADP3303 can source up to 200 mA without any heatsink

or pass transistor. If higher current is needed, an appropriate

pass transistor can be used, as in Figure 24, to increase the

output current to 1 A.

MJE253*

C2

10 F

C1

47 F

R1

50

*AAVID531002 HEATSINK IS USED

IN

OUT

ERR

GND

SD

ADP3303-5

Figure 24. High Output Current Linear Regulator

Constant Dropout Post Regulator

The circuit in Figure 25 provides high precision with low drop-

out for any regulated output voltage. It significantly reduces the

ripple from a switching regulator while providing a constant

dropout voltage, which limits the power dissipation of the LDO

to 60 mW. The ADP3000 used in this circuit is a switching

regulator in the step-up configuration.

D1

1N5817

C2

100 F

10V

L1

6.8 H

R1

120

ADP3303-3.3

IN

SD

OUT

GND

C3

2.2 F

3.3V @ 160mA

C1

100 F

10V

ADP3000-ADJ

SW1

GND

SW2

FB

R2

30.1k

1%

Q1

2N3906

Q2

2N3906

R4

274k

R3

124k

1%

Figure 25. Constant Dropout Post Regulator