MIC39300/39301
Micrel
MIC39300/39301
3A Low-Voltage Low-Dropout Regulator
General Description
The MIC39300 and MIC39301 are 3.0A low-dropout linear
voltage regulators that provide a low voltage, high-current
output with a minimum of external components. Utilizing
Micrel’s proprietary Super
βeta
PNP™ pass element, the
MIC39300/1 offers extremely low dropout (typically 400mV at
3.0A) and low ground current (typically 36mA at 3.0A).
The MIC39300/1 is ideal for PC add-in cards that need to
convert from standard 5V or 3.3V down to new, lower core
voltages. A guaranteed maximum dropout voltage of 500mV
over all operating conditions allows the MIC39300/1 to pro-
vide 2.5V from a supply as low as 3V. The MIC39300/1 also
has fast transient response for heavy switching applications.
The device requires only 47µF of output capacitance to
maintain stability and achieve fast transient response
The MIC39300/1 is fully protected with overcurrent limiting,
thermal shutdown, reversed-battery protection, reversed-
leakage protection, and reversed-lead insertion. The
MIC39301 offers a TTL-logic compatible enable pin and an
error flag that indicates under voltage and over current
conditions. Offered in fixed voltages, the MIC39300/1 comes
in the TO-220 and TO-263 packages and is an ideal upgrade
to older, NPN-based linear voltage regulators.
Features
• 3.0A minimum guaranteed output current
• 500mV maximum dropout voltage over temperature
Ideal for 3.0V to 2.5V conversion
• 1% initial accuracy
• Low ground current
• Current limiting and Thermal shutdown
• Reversed-battery protection
• Reversed-leakage protection
• Fast transient response
• TO-263 and TO-220 packaging
• TTL/CMOS compatible enable pin (MIC39301 only)
• Error flag output (MIC39301 only)
Applications
•
•
•
•
•
•
LDO linear regulator for PC add-in cards
High-efficiency linear power supplies
SMPS post regulator
Multimedia and PC processor supplies
Low-voltage microcontrollers
StrongARM™ processor supply
Ordering Information
Part Number
MIC39300-2.5BT
MIC39300-2.5BU
MIC39301-2.5BT
MIC39301-2.5BU
Voltage
2.5V
2.5V
2.5V
2.5V
Junction Temp. Range
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
Package
3-lead TO-220
3-lead TO-263
5-lead TO-220
5-lead TO-263
Typical Application
MIC39300-2.5
V
IN
3.3V
IN
OUT
GND
47µF
V
OUT
2.5V
ENABLE
SHUTDOWN
100kΩ
MIC39301-2.5
EN
IN
FLG
OUT
GND
47µF
ERROR FLAG
OUTPUT
V
IN
3.3V
V
OUT
2.5V
MIC39300
StrongARM is a trademark of Advanced RISC Machines, Ltd.
MIC39301
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
March 2000
1
MIC39300/39301
MICREL [ MICREL SEMICONDUCTOR ]
