ADP3300

–8–

REV. A

6-Lead Surface Mount Package

(SOT-23)

0.122 (3.10)

0.106 (2.70)

PIN 1

0.071 (1.80)

0.059 (1.50)

0.118 (3.00)

0.098 (2.50)

0.075 (1.90)

BSC

0.037 (0.95) BSC

1

3

4

5

6

2

0.009 (0.23)

0.003 (0.08)

0.022 (0.55)

0.014 (0.35)

10

°

0

°

0.020 (0.50)

0.010 (0.25)

0.059 (0.15)

0.000 (0.00)

0.051 (1.30)

0.035 (0.90)

SEATING

PLANE

0.057 (1.45)

0.035 (0.90)

OUTLINE DIMENSIONS

Dimensions shown in inches and (mm).

D1

1N5817

C2

100µF

10V

L1

6.8 H

R1

120

Ω

ADP3300-5

IN

OUT

GND

C3

2.2 F

5V @ 50mA

C1

100 F

10V

ADP3000-ADJ

SW1

GND

SW2

FB

R2

30.1k

Ω

1%

Q1

2N3906

Q2

2N3906

R4

274k

Ω

R3

124k

Ω

1%

Figure 24. Constant Dropout Post Regulator

Constant Dropout Post Regulator

The circuit in Figure 24 provides high precision with low dropout

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 15 mW. The ADP3000 used in this circuit is a

switching regulator in the step-up configuration.