August
2005 1
M9999-082605-B
MIC39500/39501
MIC39500/39501
5A µCap Low-Voltage Low-Dropout Regulator
General Description
The MIC39500 and MIC39501 are 5A low-dropout linear
voltage regulators that provide a low-voltage, high-current
output with a minimum of external components. Utilizing
Micrel’s proprietary Super
β
eta PNP™ pass element, the
MIC39500/1 offers extremely low dropout (typically 400mV
at 5A) and low ground current (typically 70mA at 5A).
The MIC39500/1 is ideal for PC Add-In cards that need to
convert from standard 2.5V or 3.3V, down to new, lower
core voltages. A guaranteed maximum dropout voltage of
500mV over all operating conditions allows the MIC39500/1
to provide 2.5V from a supply as low as 3V or 1.8V from
2.5V. The MIC39500/1 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 MIC39500/1 is fully protected with overcurrent limiting,
thermal shutdown, reversed-battery protection, reversed-
lead insertion protection, and reversed-leakage protection.
The MIC39501 offers a TTL-logic-compatible enable pin and
an error fl ag that indicates undervoltage and overcurrent
conditions. Offered in a fi xed voltages, 1.8V and 2.5V, the
MIC39500/1 comes in the TO-220 and TO-263 packages
and an ideal upgrade to older, NPN-based linear voltage
regulators.
For applications requiring input voltage
greater than 16V, see the
MIC29500/1/2/3 family. For applications
with input voltage 6V or below, see
MIC3750x LDOs.
Typical Application
IN OUT
GND
VIN
3.3V
VOUT
2.5V
1.0µF 47µF
MIC39500-2.5
MIC39500
Features
• 5A minimum guaranteed output current
• 400mV dropout voltage
Ideal for 3.0V to 2.5V conversion
Ideal for 2.5V to 1.8V conversion
• 1% initial accuracy
• Low ground current
• Current limiting and thermal shutdown
• Reversed-battery and reversed-lead insertion protection
• Reversed-leakage protection
• Fast transient response
• TO-263 and TO-220 packages
• TTL/CMOS compatible enable pin (MIC39501 only)
• Error fl ag output (MIC39501 only)
• Ceramic capacitor stable (See Application Information)
Applications
• Low Voltage Digital ICs
• LDO linear regulator for PC add-in cards
• High-effi ciency linear power supplies
• SMPS post regulator
• Multimedia and PC processor supplies
• Low-voltage microcontrollers
• StrongARM™ processor supply
StrongARM is a trademark of Advanced RISC Machines, Ltd.
MIC39501-2.5
FLG
OUT
ERROR
FLAG OUTPUT
47µF
EN
GND
IN VOUT
2.5V
1.0µF
Enable
Shutdown
VIN
3.3V
100KΩ
MIC39501
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
MIC39500/39501 Micrel
M
9999-
082605-B
2 August 2005
Pin Description
Pin Number Pin Number Pin Name Pin Function
MIC39500 MIC39501
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 output. Active low indicates an output
fault condition.
Pin Confi guration
Pin Number Pin Number Pin Name Pin Function
MIC39500 MIC39501
2,
3 4 OUT Regulator Output
5 FLG Error Flag (Ouput): Open collector output. Active low indicates an output
Pin Number Pin Number Pin Name Pin Function
MIC39500 MIC39501
1 EN Enable (Input): TTL/CMOS compatible input. Logic high = enable; logic low
1 2 IN Unregulated Input: +16V maximum supply.
3,
3 4 OUT Regulator Output
5 FLG Error Flag (Ouput): Open collector output. Active low indicates an output
Pin Number Pin Number Pin Name Pin Function
1 EN Enable (Input): TTL/CMOS compatible input. Logic high = enable; logic low
1 2 IN Unregulated Input: +16V maximum supply.
GND Ground: Ground pin and
3 4 OUT Regulator Output
5 FLG Error Flag (Ouput): Open collector output. Active low indicates an output
Pin Number Pin Number Pin Name Pin Function
1 EN Enable (Input): TTL/CMOS compatible input. Logic high = enable; logic low
1 2 IN Unregulated Input: +16V maximum supply.
GND Ground: Ground pin and
3 4 OUT Regulator Output
5 FLG Error Flag (Ouput): Open collector output. Active low indicates an output
TAB
3 OUT
2 GND
1 IN
MIC39500-x.xBT
TO-220-3 (T)
TAB
5 FLG
4 OUT
3 GND
2 IN
1 EN
MIC39501-x.xBT
TO-220-5 (T)
TAB
3 OUT
2 GND
1 IN
MIC39500-x.xBU
TO-263-3 (U)
TAB
5 FLG
4 OUT
3 GND
2 IN
1 EN
MIC39501-x.xBU
TO-263-5 (U)
Ordering Information
Part Number
Voltage
Junction Temp. Range
Package
Standard
RoHS Compliant*
MIC39500-2.5BT
MIC39500-2.5WT*
2.5V
-
40
°
C to +125
°
C
3
-Lead TO-220
MIC39500-2.5BU
MIC39500-2.5WU*
2.5V
-
40
°
C to +125
°
C
3-Lead TO-263
MIC39501-2.5BT
MIC39501-2.5WT*
2.5V
-
40
°
C to +125
°
C
5-Lead TO-220
MIC39501-2.5BU
MIC39501-2.5WU*
2.5V
-
40
°
C to +125
°
C
5-Lead TO-263
MIC39500-1.8BT
MIC39500-1.8WT*
1.8V
-
40
°
C to +125
°
C
3-Lead TO-220
MIC39500-1.8BU
MIC39500-1.8WU*
1.8V
-
40
°
C to +125
°
C
3-Lead TO-263
MIC39501-1.8BT
MIC39501-1.8WT*
1.8V
-
40
°
C to +125
°
C
5-Lead TO-220
MIC39501-1.8BU
MIC39501-1.8WU*
1.8V
-
40
°
C to +125
°
C
5-Lead TO-263
* RoHS compliant with high-melting solder exemption.
August
2005 3
M9999-082605-B
MIC39500/39501 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
(θ
JC
)
.........................................................
2°C/W
TO-220 (
θ
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
≤ 5A, V
OUT
+ 1V ≤ V
IN
≤ 16V
–2
2
%
Line Regulation I
OUT
= 10mA, V
OUT
+ 1V ≤ V
IN
≤ 16V 0.06 0.5 %
Load Regulation V
IN
= V
OUT
+ 1V, 10mA ≤ I
OUT
≤ 5A 0.2 1 %
∆V
OUT
/∆T Output Voltage Temp. Coeffi cient,
20 100
ppm/°C
Note 5
V
DO
Dropout Voltage,
Note 6
I
OUT
= 250mA, ∆V
OUT
= –2% 125
250
mV
I
OUT
= 2.5A, ∆V
OUT
= –2% 320 mV
I
OUT
= 5A, ∆V
OUT
= –2% 400
575
mV
I
GND
Ground Current,
Note 7
I
OU
T
= 2.5A, V
IN
= V
OUT
+ 1V 15
50
mA
I
OUT
= 5A, V
IN
= V
OUT
+ 1V 70 mA
I
GND(do)
Dropout Ground Pin Current V
IN
≤ V
OUT(nominal)
– 0.5V, I
OUT
= 10mA 2.1 mA
I
OUT(lim)
Current Limit V
OUT
= 0V, V
IN
= V
OUT
+ 1V 7.5 A
e
n
Output Noise Voltage C
OUT
= 47µF, I
OUT
= 100mA, 10Hz to 100kHz 260
µV(rms)
Enable Input (MIC39501)
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
30 35 µA
75
µA
V
EN
= 0.8V 2 µA
4
µA
I
OUT(shdn)
Shutdown Output Current
Note 8
10
20
µA
Flag Output (MIC39501)
I
FLG(leak)
Output Leakage Current V
OH
= 16V 0.01 1 µA
2
µA
V
FLG(do)
Output Low Voltage V
IN
= 2.250V, I
OL
, = 250µA,
Note 9
180 300 mV
400
mV
Low Threshold 1% of V
OUT
93 %
V
FLG
High Threshold 1% of V
OUT
99.2 %
Hysteresis 1 %
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
– TA
– T
)
÷
θ
JA
, where
θ
JA
depends upon the printed circuit layout. See “Applications Information.”
JA depends upon the printed circuit layout. See “Applications Information.”
JA
Note 5.
Output voltage temperature coeffi cient is ∆V
OUT(worst case)
÷
(T
J(max)
– T
J(min)
) where T
J(max)
is +125°C and T
J(min)
is –40°C.
Note 6.
V
DO
= V
IN
– V
OUT
when V
OUT
decreases to 98% of its nominal output voltage with V
IN
= V
OUT
+ 1V. For voltages below 2.25V, Dropout volt-
age is the input-to-output voltage differential with the minimum input voltage being 2.25V. Minimum input operating voltage is 2.25V.
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).
Symbol Parameter Condition Min Typ Max Units
Output Voltage 10mA
Load Regulation V
/∆T Output Voltage Temp. Coeffi cient,
Dropout Voltage,
I
I
Ground Current,
I
Dropout Ground Pin Current V
Current Limit V
Output Noise Voltage C
Symbol Parameter Condition Min Typ Max Units
Output Voltage 10mA
Line Regulation I
Load Regulation V
I
I
I
I
Dropout Ground Pin Current V
Current Limit V
Output Noise Voltage C
Symbol Parameter Condition Min Typ Max Units
–2
≤ 16V 0.06 0.5 %
≤ 5A 0.2 1 %
20 100
= –2% 125
= –2% 320 mV
= –2% 400
+ 1V 15
+ 1V 70 mA
= 10mA 2.1 mA
+ 1V 7.5 A
= 100mA, 10Hz to 100kHz 260
Symbol Parameter Condition Min Typ Max Units
1 1 %
≤ 16V 0.06 0.5 %
≤ 5A 0.2 1 %
20 100
= –2% 125
= –2% 320 mV
= –2% 400
+ 1V 15
+ 1V 70 mA
= 10mA 2.1 mA
+ 1V 7.5 A
= 100mA, 10Hz to 100kHz 260
Symbol Parameter Condition Min Typ Max Units
1 1 %
≤ 16V 0.06 0.5 %
≤ 5A 0.2 1 %
20 100
= –2% 320 mV
+ 1V 70 mA
= 10mA 2.1 mA
+ 1V 7.5 A
= 100mA, 10Hz to 100kHz 260
Symbol Parameter Condition Min Typ Max Units
1 1 %
%
≤ 16V 0.06 0.5 %
≤ 5A 0.2 1 %
= –2% 320 mV
+ 1V 70 mA
= 10mA 2.1 mA
+ 1V 7.5 A
Enable Input Voltage logic low (off)
logic high (on)
Enable Input Current V
V
Shutdown Output Current
Enable Input Voltage logic low (off)
logic high (on)
Enable Input Current V
V
Enable Input Voltage logic low (off)
30 35 µA
= 0.8V 2 µA
10
Enable Input Voltage logic low (off)
30 35 µA
= 0.8V 2 µA
10
30 35 µA
= 0.8V 2 µA
30 35 µA
= 0.8V 2 µA
µA
Output Leakage Current V
Output Low Voltage V
High Threshold 1% of V
Hysteresis 1 %
Output Leakage Current V
Output Low Voltage V
Low Threshold 1% of V
High Threshold 1% of V
Hysteresis 1 %
= 16V 0.01 1 µA
180 300 mV
OUT
Hysteresis 1 %
= 16V 0.01 1 µA
180 300 mV
93 %
OUT
Hysteresis 1 %
= 16V 0.01 1 µA
180 300 mV
93 %
Hysteresis 1 %
= 16V 0.01 1 µA
µA
180 300 mV
mV
93 %
99.2 %
Hysteresis 1 %
MIC39500/39501 Micrel
M
9999-
082605-B
4 August 2005
Typical Characteristics
0
5
10
15
20
25
30
35
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6
PSRR (dB)
FREQUENCY (Hz)
P ower S upply
R ejection R atio
CIN = 0
COUT = 47µF T ant
VIN = 3.3V
VOUT = 2.5V
ILOAD = 5A
10 1001k 10k 100k 1M 10M
0
5
10
15
20
25
30
35
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6
PSRR (dB)
FREQUENCY (Hz)
P ower S upply
R ejection R atio
CIN = 0
COUT = 100µF C era mic
10 1001k 10k 100k 1M 10M
VIN = 3.3V
VOUT = 2.5V
ILOAD = 5A
0
50
100
150
200
250
300
350
400
450
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
DROPOUT VOLTAGE (mV)
OUTPUT CURRENT (mA)
Dropout V oltage vs .
Output C urrent
VOUT = 2.5V
VOUT = 1.8V
0
100
200
300
400
500
600
-40
-20
0
20
40
60
80
100
120
140
DROPOUT VOLTAGE (mV)
TEMPERATURE (°C)
Dropout V oltage
vs . T emperature
ILOAD = 5A
VOUT = 2.5V
VOUT = 1.8V
1.4
1.6
1.8
2
2.2
2.4
2.6
2.8
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
OUTPUT VOLTAGE (V)
INPUT VOLTAGE (V)
Dropout C harac teris tics
ILOAD = 2.5A
ILOAD = 100mA
ILOAD = 5A
0
10
20
30
40
50
60
70
80
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
GROUND CURRENT (mA)
OUTPUT CURRENT (mA)
G round C urrent vs .
Output C urrent
VOUT = 2.5V
VIN = V O UT +1V
VOUT = 1.8V
0.0
2.0
4.0
6.0
8.0
10.0
12.0
012345678910
GROUND CURRENT (mA)
SUPPLY VOLTAGE (V)
G round C urrent vs .
S uppl
y
Voltage
ILOAD = 10mA
ILOAD = 100mA
0
20
40
60
80
100
120
140
160
180
0246810
GROUND CURRENT (mA)
SUPPLY VOLTAGE (V)
G round C urrent vs .
S uppl
y
Voltage
ILOAD = 5.0A
ILOAD = 2.5A
ILOAD = 2.0A
0
1
2
3
4
5
6
7
8
9
10
-40 -20 0 20 40 60 80 100120 140
GROUND CURRENT (mA)
TEMPERATURE (°C)
G round C urrent
vs . Temperature
VOUT = 1.8V
VOUT = 2.5V
ILOAD = 10mA
VIN = V OUT + 1V
0
5
10
15
20
25
30
-40 -20 0 20 40 60 80 100 120 140
GROUND CURRENT (mA)
TEMPERATURE (°C)
G round C urrent
vs . T emperature
VOUT = 2.5V
ILOAD = 2.5A
VIN = V O UT + 1V
VOUT = 1.8V
0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
-40 -20 0 20 40 60 80 100 120 140
GROUND CURRENT (mA)
TEMPERATURE (°C)
G round C urrent
vs . T emperature
ILOAD = 5A
VIN = V O UT = 1V
VOUT = 1.8V
VOUT = 2.5V
0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
-40 -20 0 20 40 60 80 100 120 140
SHORT CIRCUIT CURRENT (A)
TEMPERATURE (°C)
S hort C irc uit C urrent
vs . T emperature
VIN = V O UT + 1V
T ypical 1.8V Device
T ypical 2.5V Device
August
2005 5
M9999-082605-B
MIC39500/39501 Micrel
0
1
2
3
4
5
6
0.001
0.01
0.1
1
10
100
1000
10000
100000
FLAG VOLTAGE (V)
RESISTANCE (kΩ)
E rror F lag P ull-up R es is tor
F lag_HIG H (O K )
F lag_LO W
(F AUL T )
0
1
2
3
4
5
6
7
-40 -20 0 20 40 60 80 100120 140
ENABLE CURRENT (µA)
TEMPERATURE (°C)
E nable C urrent
vs . Temperature
VE N = 2.25V
VIN = V OUT + 1V
0
50
100
150
200
250
300
350
-40 -20 0 20 40 60 80 100120 140
FLAG VOLTAGE (V)
TEMPERATURE (°C)
F lag L ow V oltage
vs . Temperature
VIN = 2.8V
RP UL L-UP = 22kΩ
MIC39500/39501 Micrel
M
9999-
082605-B
6 August 2005
Functional Diagram
Ref.
18V
O.V.
ILIMIT
Thermal
Shut-
down
1.240V1.180V
EN*
IN
FLAG*
GND
OUT
* MIC39501 only
August
2005 7
M9999-082605-B
MIC39500/39501 Micrel
Applications Information
The MIC39500/1 is a high-performance low-dropout voltage
regulator suitable for moderate to high-current voltage regula-
tor applications. Its 400mV dropout voltage at full load makes
it especially valuable in battery-powered systems and as a
high-effi ciency noise fi lter in post-regulator applications. Un-
like older NPN-pass transistor designs, where the minimum
dropout voltage is limited by the base-to-emitter voltage drop
and collector-to-emitter saturation voltage, dropout perfor-
mance of the PNP output of these devices is limited only by
the low V
CE
saturation voltage.
A trade-off for the low dropout voltage is a varying base drive
requirement. Micrel’s Super
β
eta PNP™ process reduces this
drive requirement to only 2% to 5% of the load current.
The MIC39500/1 regulator is fully protected from damage due
to fault conditions. Current limiting is provided. This limiting is
linear; output current during overload conditions is constant.
Thermal shutdown disables the device when the die tempera-
ture exceeds the maximum safe operating temperature. Tran-
sient protection allows device (and load) survival even when
the input voltage spikes above and below nominal. The output
structure of these regulators allows voltages in excess of the de-
sired output voltage to be applied without reverse current fl ow.
MIC39500-x.x
IN OUT
GND
CIN COUT
VIN VOUT
Figure 1. Capacitor Requirements
Thermal Design
Linear regulators are simple to use. The most complicated
design parameters to consider are thermal characteristics.
Thermal design requires four application-specifi c param-
eters:
• Maximum ambient temperature (T
A
• Maximum ambient temperature (TA
• Maximum ambient temperature (T
)
• Output Current (I
OUT
)
• Output Voltage (V
OUT
)
• Input Voltage (V
IN
)
• Ground Current (I
GND
)
Calculate the power dissipation of the regulator from these
numbers and the device parameters from this datasheet,
where the ground current is taken from data sheet.
P
D
= (V
IN
– V
OUT
)
×
I
OUT
+ V
IN
×
I
GND
The heat sink thermal resistance is determined by:
where:
T
J (max)
≤ 125°C and
θ
CS
is between 0° and 2°C/W.
The heat sink may be signifi cantly reduced in applications
where the minimum input voltage is known and is large com-
pared with the dropout voltage. Use a series input resistor
to drop excessive voltage and distribute the heat between
this resistor and the regulator. The low-dropout properties of
Micrel Super
β
eta PNP regulators allow signifi cant reductions
in regulator power dissipation and the associated heat sink
without compromising performance. When this technique
is employed, a capacitor of at least 1µF is needed directly
between the input and regulator ground.
Refer to
Application Note 9
for further details and examples
on thermal design and heat sink specifi cation.
Output capacitor
The MIC39500/1 requires an output capacitor to maintain
stability and improve transient response. Proper capaci-
tor selection is important to ensure proper operation. The
MIC39500/1 output capacitor selection is dependent upon the
ESR (equivalent series resistance) of the output capacitor to
maintain stability. When the output capacitor is 47µF or greater,
the output capacitor should have less than 1Ω of ESR. This
will improve transient response as well as promote stability.
Ultra-low-ESR capacitors, such as ceramic chip capacitors
may promote instability. These very low ESR levels may
cause an oscillation and/or underdamped transient response.
When larger capacitors are used, the ESR requirement ap-
proaches zero. A 100µF ceramic capacitor can be used on
the output while maintaining stability. A low-ESR 47µF solid
tantalum capacitor works extremely well and provides good
transient response and stability over temperature. Aluminum
electrolytics can also be used, as long as the ESR of the
capacitor is
<
1Ω.
The value of the output capacitor can be increased without
limit. Higher capacitance values help to improve transient
response and ripple rejection and reduce output noise.
Input capacitor
An input capacitor of 1µF or greater is recommended when
the device is more than 4 inches away from the bulk ac supply
capacitance, or when the supply is a battery. Small surface-
mount ceramic chip capacitors can be used for bypassing.
Larger values will help to improve ripple rejection by bypass-
ing the input to the regulator, further improving the integrity
of the output voltage.
Transient Response and 3.3V to 2.5V or 2.5V to 1.8V
Conversion
The MIC39500/1 has excellent transient response to varia-
tions in input voltage and load current. The device has been
designed to respond quickly to load current variations and
input voltage variations. Large output capacitors are not re-
quired to obtain this performance. A standard 47µF output
capacitor, preferably tantalum, is all that is required. Larger
values improve performance even further.
By virtue of its low-dropout voltage, this device does not
saturate into dropout as readily as similar NPN-based de-
signs. When converting from 3.3V to 2.5V, or 2.5V to 1.8V,
the NPN-based regulators are already operating in dropout,
with typical dropout requirements of 1.2V or greater. To con-
vert down to 2.5V without operating in dropout, NPN-based
regulators require an input voltage of 3.7V at the very least.
The MIC39500/1 regulator provides excellent performance
MIC39500/39501 Micrel
M
9999-
082605-B
8 August 2005
with an input as low as 3.0V or 2.5V respectively. This gives
PNP-based regulators a distinct advantage over older, NPN-
based linear regulators.
A typical NPN regulator does not have the headroom to do
this conversion.
Minimum Load Current
The MIC39500/1 regulator is specifi ed between fi nite loads.
If the output current is too small, leakage currents dominate
and the output voltage rises. A 10mA minimum load current
is necessary for proper regulation.
Error Flag
The MIC39501 version features an error fl ag circuit which
monitors the output voltage and signals an error condition
when the voltage 5% below the nominal output voltage. The
error fl ag is an open-collector output that can sink 10mA
during a fault condition.
Low output voltage can be caused by a number of problems,
including an overcurrent fault (device in current limit) or low
input voltage. The fl ag is inoperative during overtemperature
shutdown.
When the error fl ag is not used, it is best to leave it open.
The fl ag pin can be tied directly to pin 4, the output pin.
Enable Input
The MIC39501 version features an enable input for on/off
control of the device. Its shutdown state draws “zero” cur-
rent (only microamperes of leakage). The enable input is
TTL/CMOS compatible for simple logic interface, but can be
connected to up to 20V.
August
2005 9
M9999-082605-B
MIC39500/39501 Micrel
Package Information
3-Lead TO-263 (U)
3-Lead T
O-220 (T)
MIC39500/39501 Micrel
M
9999-
082605-B
10
August 2005
1
θ
θ1
3
θ
4
θ
1
θ
2
θ
5-Lead TO-263-5 (U)
5-Lead T
O-220 (T)
MICREL INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL
+ 1 (408) 944-0800
FAX
+ 1 (408) 474-1000
WEB
http://www.micrel.com
This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use.
Micrel reserves the right to change circuitry and specifi cations at any time without notifi cation to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can
reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into
the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a signifi cant injury to the user. A Purchaser's
use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser's own risk and Purchaser agrees to fully indemnify
Micrel for any damages resulting from such use or sale.
© 2005 Micrel Incorporated
