8181
LOW-DROPOUT,
5 V REGULATOR
8181
LOW-DROPOUT, 5 V REGULATOR
— HIGH EFFICIENCY
Especially suited for hand-held, portable, battery-operated equip-
ment such as cellular telephones, the A8181SLB low dropout voltage
regulator provides high efficiency for maximum battery life in a mini-
mum package size. Equally applicable to camcorders and portable
computers, the device provides a fixed 5 V regulated continuous output
at almost 200 mA of load current under worst-case conditions. Under
normal operating conditions, output currents over 500 mA are
permitted.
A MOSFET pass element delivers high output current with an
input-output differential of less than 300 mV. For high efficiency, the
low dropout voltage allows a longer battery discharge before output
voltage regulation is lost. A low quiescent current, even during high
load conditions, makes the device ideal for standby power systems.
High regulator accuracy and excellent temperature characteristics are
provided by a bandgap reference. An enable input gives the designer
complete control over sequential power-up or emergency shutdown.
This device is supplied in a 16-lead wide-body, small-outline
plastic power package (SOIC) for surface-mount applications. The
copper batwing provides for maximum package power dissipation in
the smallest possible construction. The A8181SLB is rated for opera-
tion over a temperature range of -20°C to +85°C.
Data Sheet
27468*
GROUND
GROUND
ENABLE
ABSOLUTE MAXIMUM RATINGS
at T
A
= +25°C
Input Voltage, V
I
...................................
10 V
Output Current, I
O
(40% duty cycle) ............................
1 A*
(75% duty cycle) .....................
500 mA*
(continuous) ............................
370 mA*
Operating Temperature Range,
T
A
.................................
-20
°
C to +85
°
C
Junction Temperature, T
J
..............
+150
°
C†
Storage Temperature Range,
T
S
...............................
-40
°
C to +150
°
C
* Output current rating is limited by input voltage,
duty cycle, and ambient temperature. Under any
set of conditions, do not exceed a junction
temperature of +150°C. See next page.
† Fault conditions that produce excessive
junction temperature will activate device thermal
shutdown circuitry. These conditions can be
tolerated but should be avoided.
T
C
U Y
D L
O N
R O
P E
D C
E N
U E
N ER
I
T F
N E
O R
C R
S O
I
D F
—
NC
NC
NC
1
2
3
4
5
16
15
14
13
12
11
10
9
OUT
OUT
NC
5V
GROUND
GROUND
NC
NC
NC
6
7
VR
IN
IN
8
Dwg. PS-018
FEATURES AND BENEFITS
s
s
s
s
s
High Efficiency Provides Extended Battery Life
Less Than 300 mV Dropout Voltage
Low Quiescent Current
>200 mA Output Current
LSTTL-Compatible ON/OFF Control
For Sequential Power-up or Emergency Shutdown
s
Internal Thermal Protection
s
SOIC Surface-Mount Package
Always order by complete part number:
A8181SLB
.
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
