March 2000
1
MIC39300/39301
MIC39300/39301
Micrel
MIC39300/39301
3A Low-Voltage Low-Dropout Regulator
Micrel, Inc. 1849 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 944-0970 http://www.micrel.com
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
eta PNPTM 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 47
F 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.
Typical Application
MIC39300-2.5
IN
OUT
GND
47F
V
IN
3.3V
V
OUT
2.5V
MIC39300
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
StrongARMTM processor supply
StrongARM is a trademark of Advanced RISC Machines, Ltd.
Ordering Information
Part Number
Voltage
Junction Temp. Range
Package
MIC39300-2.5BT
2.5V
40
C to +125
C
3-lead TO-220
MIC39300-2.5BU
2.5V
40
C to +125
C
3-lead TO-263
MIC39301-2.5BT
2.5V
40
C to +125
C
5-lead TO-220
MIC39301-2.5BU
2.5V
40
C to +125
C
5-lead TO-263
MIC39301-2.5
IN
OUT
GND
47F
V
IN
3.3V
V
OUT
2.5V
EN
FLG
ERROR FLAG
OUTPUT
ENABLE
SHUTDOWN
100k
MIC39301
MIC39300/39301
Micrel
MIC39300/39301
2
March 2000
Pin Description
Pin Number
Pin Number
Pin Name
Pin Function
MIC39300
MIC39301
1
EN
Enable (Input): TTL/CMOS compatible input. Logic high = enable; logic low
or open = shutdown.
1
2
IN
Unregulated Input: +16V maximum supply.
2,
TAB
3,
TAB
GND
Ground: Ground pin and
TAB
are internally connected.
3
4
OUT
Regulator Output
5
FLG
Error Flag (Ouput): Open-collector indicates an output fault condition.
Active low.
Pin Configuration
TAB
3
OUT
2
GND
1
IN
MIC39300-x.xBT
TO-220-3 (T)
TAB
5
FLG
4
OUT
3
GND
2
IN
1
EN
MIC39301-x.xBT
TO-220-5 (T)
TAB
3
OUT
2
GND
1
IN
MIC39300-x.xBU
TO-263-3 (U)
TAB
5
FLG
4
OUT
3
GND
2
IN
1
EN
MIC39301-x.xBU
TO-263-5 (U)
March 2000
3
MIC39300/39301
MIC39300/39301
Micrel
Absolute Maximum Ratings
(Note 1)
Supply Voltage (V
IN
) ..................................... 20V to +20V
Enable Voltage (V
EN
) .................................................. +20V
Storage Temperature (T
S
) ....................... 65
C to +150
C
Lead Temperature (soldering, 5 sec.) ....................... 260
C
ESD, Note 3
Operating Ratings
(Note 2)
Supply Voltage (V
IN
) .................................. +2.25V to +16V
Enable Voltage (V
EN
) .................................................. +16V
Maximum Power Dissipation (P
D(max)
) ..................... Note 4
Junction Temperature (T
J
) ....................... 40
C to +125
C
Package Thermal Resistance
TO-263
(
JC
) ......................................................... 2
C/W
TO-220 (
JC
) ......................................................... 2
C/W
Electrical Characteristics
T
J
= 25
C, bold values indicate 40
C
T
J
+125
C; unless noted
Symbol
Parameter
Condition
Min
Typ
Max
Units
V
OUT
Output Voltage
10mA
1
1
%
10mA
I
OUT
3A, V
OUT
+ 1V
V
IN
8V
2
2
%
Line Regulation
I
OUT
= 10mA, V
OUT
+ 1V
V
IN
8V
0.06
0.5
%
Load Regulation
V
IN
= V
OUT
+ 1V, 10mA
I
OUT
3A
0.2
1
%
V
OUT
/
T
Output Voltage Temp. Coefficient,
20
100
ppm/
C
Note 5
V
DO
Dropout Voltage, Note 6
I
OUT
= 100mA,
V
OUT
= 1%
80
200
mV
I
OUT
= 750mA,
V
OUT
= 1%
200
mV
I
OUT
= 1.5A,
V
OUT
= 1%
320
mV
I
OUT
= 3A,
V
OUT
= 1%
400
500
mV
I
GND
Ground Current, Note 7
I
OUT
= 750mA, V
IN
= V
OUT
+ 1V
10
20
mA
I
OUT
= 1.5A, V
IN
= V
OUT
+ 1V
17
mA
I
OUT
= 3A, V
IN
= V
OUT
+ 1V
45
mA
I
GND(do)
Dropout Ground Pin Current
V
IN
V
OUT(nominal)
0.5V, I
OUT
= 10mA
6
mA
I
OUT(lim)
Current Limit
V
OUT
= 0V, V
IN
= V
OUT
+ 1V
4.5
A
Enable Input (MIC39301)
V
EN
Enable Input Voltage
logic low (off)
0.8
V
logic high (on)
2.25
V
I
IN
Enable Input Current
V
EN
= V
IN
15
30
A
75
A
V
EN
= 0.8V
2
A
4
A
I
OUT(shdn)
Shutdown Output Current
Note 8
10
20
A
Flag Output (MIC39301)
I
FLG(leak)
Output Leakage Current
V
OH
= 16V
0.01
1
A
2
A
V
FLG(do)
Output Low Voltage
V
IN
= 2.250V, I
OL
, = 250
A, Note 9
220
300
mV
400
mV
V
FLG
Low Threshold
% of V
OUT
93
%
High Threshold
99.2
%
Hysteresis
1
%
MIC39300/39301
Micrel
MIC39300/39301
4
March 2000
Note 1.
Exceeding the absolute maximum ratings may damage the device.
Note 2.
The device is not guaranteed to function outside its operating rating.
Note 3.
Devices are ESD sensitive. Handling precautions recommended.
Note 4.
P
D(max)
= (T
J(max)
T
A
)
JA
, where
JA
depends upon the printed circuit layout. See "Applications Information."
Note 5.
Output voltage temperature coefficient is
V
OUT(worst case)
(T
J(max)
T
J(min)
) where T
J(max)
is +125
C and T
J(min)
is 0
C.
Note 6.
V
DO
= V
IN
V
OUT
when V
OUT
decreases to 99% of its nominal output voltage with V
IN
= V
OUT
+ 1V.
Note 7.
I
GND
is the quiescent current. I
IN
= I
GND
+ I
OUT
.
Note 8.
V
EN
0.8V, V
IN
8V, and V
OUT
= 0V
Note 9.
For a 2.5V device, V
IN
= 2.250V (device is in dropout).
March 2000
5
MIC39300/39301
MIC39300/39301
Micrel
Typical Characteristics
0
10
20
30
40
50
1x10
1
1x10
2
1x10
3
1x10
4
1x10
5
1x10
6
PSRR (dB)
FREQUENCY (Hz)
Power Supply
vs. Ripple Rejection
V
OUT
= 2.5V
V
IN
= 3.3V
C
OUT
= 47
F
I
LOAD
= 3A
0
10
20
30
40
50
1x10
1
1x10
2
1x10
3
1x10
4
1x10
5
1x10
6
PSRR (dB)
FREQUENCY (Hz)
Power Supply
vs. Ripple Rejection
V
OUT
= 2.5V
V
IN
= 3.3V
C
OUT
= 100
F
I
LOAD
= 3A
0
50
100
150
200
250
300
350
400
0
1000
2000
3000
DROPOUT VOLTAGE (mV)
OUTPUT CURRENT (mA)
Dropout Voltage
vs. Output Current
0
100
200
300
400
500
600
-40 -20 0
20 40 60 80 100 120
DROPOUT VOLTAGE (mV)
TEMPERATURE (
C)
Dropout Voltage
vs. Temperature
V
OUT
= 2.5V
I
LOAD
= 3A
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
1.2
1.6
2.0
2.4
2.8
3.2
3.6
OUTPUT VOLTAGE (V)
INPUT VOLTAGE (V)
Dropout Characteristics
I
LOAD
= 100mA
I
LOAD
= 1.5A
I
LOAD
= 3A
0
10
20
30
40
50
0
1000
2000
3000
GROUND CURRENT (mA)
OUTPUT CURRENT (mA)
Ground Current
vs. Output Current
V
OUT
= 2.5V
I
LOAD
= 3A
0
2
4
6
8
10
0
2
4
6
8
10
12
GROUND CURRENT (mA)
SUPPLY VOLTAGE (V)
Ground Current
vs. Supply Voltage
I
LOAD
= 10mA
I
LOAD
= 100mA
0
10
20
30
40
50
60
70
80
90
100
0
2
4
6
8
10
12
GROUND CURRENT (mA)
SUPPLY VOLTAGE (V)
Ground Current
vs. Supply Voltage
I
LOAD
=
1000mA
I
LOAD
= 3000mA
I
LOAD
= 1500mA
0
1
2
3
4
5
6
7
8
-40 -20 0
20 40 60 80 100 120
GROUND CURRENT (mA)
TEMPERATURE (
C)
Ground Current
vs. Temperature
V
OUT
= 2.5V
I
LOAD
= 100mA
0
5
10
15
20
25
-40 -20 0
20 40 60 80 100 120
GROUND CURRENT (mA)
TEMPERATURE (
C)
Ground Current
vs. Temperature
V
OUT
= 2.5V
I
LOAD
= 1.5A
0
10
20
30
40
50
60
-40 -20 0
20 40 60 80 100 120
GROUND CURRENT (mA)
TEMPERATURE (
C)
Ground Current
vs. Temperature
V
OUT
= 2.5V
I
LOAD
= 3A
0
1
2
3
4
5
6
-40 -20 0
20 40 60 80 100 120
SHORT CIRCUIT CURRENT (A)
TEMPERATURE (
C)
Short Circuit vs.
Temperature
V
IN
= 3.5V
(typical 2.5V device)
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