AS1521
300mA Low Dropout Voltage Regulator
(PRELIMINARY INFORMATION)
FEATURES
APPLICATIONS
• Battery Powered Systems
• Cordless Telephones
• 1% Output Accuracy @ 2.5V, 3.3V, 5V, @ 300mA Output
• Very Low Quiescent Current
• Radio Control Systems
• Portable/Palm Top/Notebook Computers
• Portable Consumer Equipment
• Portable Instrumentation
• Bar Code Scanners
• 0.42V (Typ.) Dropout Voltage @ 300mA
• Extremely Tight Load And Line Regulation
• Current & Thermal Limiting
• Logic-Controlled Electronic Shutdown
• Reverse Battery Protection
• Output Programmable From 1.24 To 20V
• Equivalent Replacement For LT1521
• SMPS Post-Regulator
• Voltage Reference
• Automotive Electronics
PRODUCT DESCRIPTION
The AS1521 is a low power voltage regulator. This device is an excellent choice for use in battery-powered applications such as
cordless telephones, radio control systems, and portable computers. The AS1521 features very low quiescent current and very low
dropout voltage. This includes a tight initial tolerance of 1% max, and very low output temperature coefficient, making the AS1521
useful as a low-power voltage reference.
The error flag output feature is used as power-on reset for warning of a low output voltage, due to falling voltage input of batteries.
The AS1521 is offered in a SO-8, SOT-252, TO-223, TO-220 & TO-263 packages.
ORDERING INFORMATION
SO-8
TO-252
SOT-223
TO-220
3-PIN
TO-263
3-PIN
Oper. Temp.
Range
-40°C to +125°C
3-PIN
AS1521M3-X
AS1521S-X AS1521R-X
AS1521U-X AS1521T-X
X= Output Voltage (2.5V, 3.3V, 5.0V, or Blank for Adj.)
PIN CONNECTIONS
TO-252 (R)
TO-263-3 (T)
TO-220-3 (U)
8-Pin Surface Mount (S)
SOT-223 (M3)
VOUT
3
VIN
VIN
1
2
3
4
8
7
6
5
AS1521
AS1521
2
1
GND
VOUT
SENSE/ ADJ
GND
GND
GND
SHDN
AS1521
1
2
3
1
3
2
AS1521
1
2
3
VIN GND VOUT
ERROR
Front View
Top View
VOUT GND VIN
Top View
Top View
VOUT
VIN
GND
VOUT
SHDN
Front View
<0.25V OFF
ON
ON
>2.8V
NC
Rev. 10/11/00
SIPEX [ SIPEX CORPORATION ]
