3A L
O W
D
R O P O U T
P
O S I T I V E
R
E G U L AT O R S
LX8385-xx/8385A-xx/8385B-xx
P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7
Copyright 1999
Rev. 2.0a 10/00
2
P
R O D U C T I O N
D
A T A
S
H E E T
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Power Dissipation ..................................................................................Internally Limited
Input Voltage................................................................................................................ 10V
Input to Output Voltage Differential........................................................................... 10V
Operating Junction Temperature
Plastic (P, DD & DL Packages)............................................................................. 150°C
Storage Temperature Range ...................................................................... -65°C to 150°C
Lead Temperature (Soldering, 10 seconds)............................................................. 300°C
PACKAGE PIN OUTS
Thermal
Limit Circuit
Control
Circuit
Bandgap
Circuit
Output
Circuit
Bias
Circuit
V
OUT
V
IN
SOA Protection
Circuit
Current
Limit Circuit
ADJ or
GND*
BLOCK DIAGRAM
P PACKAGE:
THERMAL RESISTANCE-JUNCTION TO TAB,
θ
JT
THERMAL RESISTANCE-JUNCTION TO AMBIENT,
θ
JA
DD PACKAGE:
THERMAL RESISTANCE-JUNCTION TO TAB,
θ
JT
THERMAL RESISTANCE-JUNCTION TO AMBIENT,
θ
JA
3.0°C/W
60°C/W
3.0°C/W
*60°C/W
Junction Temperature Calculation: T
= T
+ (P
x
θ
).
The
θ
numbers are guidelines for the thermal performance of the device/pc-board system.
All of the above assume no ambient airflow.
*
θ
can be improved with package soldered to 0.5IN
2
copper area over backside ground
plane or internal power plane.
θ
JA
can vary from 20oC/W to > 40oC/W depending on
mounting technique.
THERMAL DATA
3
2
1
P PACKAGE
(Top View)
* Pin 1 is GND for fixed voltage versions.
3
2
1
DD PACKAGE
(Top View)
* Pin 1 is GND for fixed voltage versions.
Note 1. Exceeding these ratings could cause damage to the device. All voltages are with
respect to Ground. Currents are positive into, negative out of the specified terminal.
TAB IS V
OUT
TAB IS V
OUT
* This pin GND for fixed voltage versions.
V
IN
V
OUT
ADJ / GND*
V
IN
V
OUT
ADJ / GND*