ADP3303 Analog Devices, ADP3303 Datasheet - Page 8

• Manufacturer Part Number: ADP3303
• Description: High Accuracy anyCAP 100 mA Low Dropout Linear Regulator
• Manufacturer: Analog Devices

ADP3303
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.
V
IN
OUTPUT SELECT
= 5.5V TO 12V
5V
0V
V
IN
Figure 23. Crossover Switch
= 2.5V TO 3.5V
1.0 F
C1
100 F
SD
SD
IN
IN
10V
C1
ADP3303-5.0
ADP3303-3.3
GND
GND
I
LIM
ADP3000-ADJ
R1
120
GND
OUT
OUT
0.0098 (0.25)
0.0040 (0.10)
0.1574 (4.00)
0.1497 (3.80)
Figure 25. Constant Dropout Post Regulator
SEATING
V
PLANE
IN
SW2
PIN 1
C2
0.47 F
6.8 H
Dimensions shown in inches and (mm).
L1
SW1
0.1968 (5.00)
0.1890 (4.80)
0.0500
(1.27)
BSC
8
1
FB
V
OUTLINE DIMENSIONS
8-Lead Small Outline IC
OUT
0.0192 (0.49)
0.0138 (0.35)
= 5V/3.3V
0.0688 (1.75)
0.0532 (1.35)
1N5817
5
4
D1
0.2440 (6.20)
0.2284 (5.80)
(SO-8)
–8–
C2
100 F
10V
0.0098 (0.25)
0.0075 (0.19)
2N3906
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.
Q1
V
IN
Figure 24. High Output Current Linear Regulator
R2
30.1k
1%
R3
124k
1%
= 6V TO 8V
8
0
0.0196 (0.50)
0.0099 (0.25)
0.0500 (1.27)
0.0160 (0.41)
*AAVID531002 HEATSINK IS USED
IN
SD
47 F
ADP3303-3.3
C1
GND
x 45
OUT
50
R1
SD
ADP3303-5
MJE253*
Q2
2N3906
GND
R4
274k
IN
ERR
OUT
C3
2.2 F
3.3V @ 160mA
C2
10 F
V
OUT
= 5V @ 1A
REV. A