MICREL MIC5236

MIC5236
Micrel, Inc.
MIC5236
Low Quiescent Current µCap LDO Regulator
General Description
Features
The MIC5236 is a low quiescent current, µCap low-dropout
regulator. With a maximum operating input voltage of 30V and
a quiescent current of 20µA, it is ideal for supplying keep-alive
power in systems with high-voltage batteries.
Capable of 150mA output, the MIC5236 has a dropout voltage of only 300mV. It can also survive an input transient of
–20V to +60V.
As a µCap LDO, the MIC5236 is stable with either a ceramic
or a tantalum output capacitor. It only requires a 1.0µF output
capacitor for stability.
The MIC5236 includes a logic compatible enable input and
an undervoltage error flag indicator. Other features of the
MIC5236 include thermal shutdown, current-limit, overvoltage
shutdown, load-dump protection, reverse leakage protections,
and reverse battery protection.
Available in the thermally enhanced SOIC-8 and MSOP-8, the
MIC5236 comes in fixed 2.5V, 3.0V, 3.3V, 5.0V, and adjustable
voltages. For other output voltages, contact Micrel.
• Ultra-low quiescent current (IQ = 20µA @IO = 100µA)
• Wide input range: 2.3V to 30V
• Low dropout:
230mV @50mA;
300mV @150mA
• Fixed 2.5V, 3.0V, 3.3V, 5.0V, and Adjustable outputs
• ±1.0% initial output accuracy
• Stable with ceramic or tantalum output capacitor
• Load dump protection: –20V to +60V input transient
survivability
• Logic compatible enable input
• Low output flag indicator
• Overcurrent protection
• Thermal shutdown
• Reverse-leakage protection
• Reverse-battery protection
• High-power SOIC-8 and MSOP-8
Applications
• Keep-alive supply in notebook and
portable personal computers
• Logic supply from high-voltage batteries
• Automotive electronics
• Battery-powered systems
Typical Application
VIN
30V
MIC5236
IN
OUT
EN
VOUT
3.0V/100µA
VIN
5V
IGND = 20µA
ERR
MIC5236
IN
OUT
EN
GND
Regulator with Low IO and Low IQ
VIN
5V
47k
COUT
VERR
Regulator with Error Output
MIC5236
IN
OUT
EN
ERR
GND
VOUT
3.0V/150mA
R1
ADJ
GND
VOUT
3.0V/150mA
R2
Regulator with Adjustable Output
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
July 2005
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MIC5236
MIC5236
Micrel, Inc.
Ordering Information
Part Number*
Voltage
Junction Temp. Range
Package
Standard
Pb-Free
MIC5236BM
MIC5236YM
ADJ
-40°C to +125°C
8-Pin SOIC
MIC5236BMM
MIC5236YMM
ADJ
-40°C to +125°C
8-Pin MSOP
MIC5236-2.5BM
MIC5236-2.5YM
2.5V
-40°C to +125°C
8-Pin SOIC
MIC5236-2.5BMM
MIC5236-2.5YMM
2.5V
-40°C to +125°C
8-Pin MSOP
MIC5236-3.0BM
MIC5236-3.0YM
3.0V
-40°C to +125°C
8-Pin SOIC
MIC5236-3.0BMM
MIC5236-3.0YMM
3.0V
-40°C to +125°C
8-Pin MSOP
MIC5236-3.3BM
MIC5236-3.3YM
3.3V
-40°C to +125°C
8-Pin SOIC
MIC5236-3.3BMM
MIC5236-3.3YMM
3.3V
-40°C to +125°C
8-Pin MSOP
MIC5236-5.0BM
MIC5236-5.0YM
5.0V
-40°C to +125°C
8-Pin SOIC
MIC5236-5.0BMM
MIC5236-5.0YMM
5.0V
-40°C to +125°C
8-Pin MSOP
* Contact factory regarding availability for voltages not listed
Pin Configuration
ERR 1
8 GND
ADJ 1
8 GND
IN 2
7 GND
IN 2
7 GND
OUT 3
6 GND
OUT 3
6 GND
EN 4
5 GND
EN 4
5 GND
8-Pin SOIC (M)
8-Pin MSOP (MM)
8-Pin SOIC (M)
8-Pin MSOP (MM)
Pin Description
Pin Number
Pin Number
Pin Name
1
/ERR
1
2
ADJ
2
IN
3
3
OUT
4
4
EN
5–8
5–8
GND
MIC5236
Pin Function
Error (Output): Open-collector output is active low when the output is out
of regulation due to insufficient input voltage or excessive load. An external
pull-up resistor is required.
Adjustable Feedback Input. Connect to voltage divider network.
Power supply input.
Regulated Output
Enable (Input): Logic low = shutdown; logic high = enabled.
Ground: Pins 5, 6, 7, and 8 are internally connected in common via the leadframe.
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July 2005
MIC5236
Micrel, Inc.
Absolute Maximum Ratings (Note 1)
Operating Ratings (Note 2)
Supply Voltage (VIN), Note 3 .........................–20V to +60V
Power Dissipation (PD), Note 4 ............... Internally Limited
Junction Temperature (TJ) ....................................... +150°C
Storage Temperature (TS) ........................ –65°C to +150°C
Lead Temperature (soldering, 5 sec.) ........................ 260°C
ESD Rating, Note 5
Supply Voltage (VIN) .................................... + 2.3V to +30V
Junction Temperature (TJ) ........................ –40°C to +125°C
Package Thermal Resistance
MSOP (θJA) ........................................................................ 80°C/W
SOIC (θJA) .......................................................... 63°C/W
Electrical Characteristics
VIN = 6.0V; VEN = 2.0V; COUT = 4.7µF, IOUT = 100µA; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted.
Symbol
Parameter
Conditions
VOUT
Output Voltage Accuracy
variation from nominal VOUT
Min
Typ
ΔVOUT/ΔT
ppm/°C
Output Voltage
Note 6
50
–1
–2
Max
Units
1
+2
%
%
Temperature Coefficient
ΔVOUT/VOUT
Line Regulation
VIN = VOUT + 1V to 30V
0.2
0.5
1.0
%
%
ΔVOUT/VOUT
Load Regulation
IOUT = 100µA to 50mA, Note 7
0.15
0.3
0.5
%
%
IOUT = 100µA to 150mA, Note 7
0.3
0.6
1.0
%
%
IOUT = 100µA
50
100
mV
IOUT = 50mA
230
400
mV
IOUT = 150mA
ΔV
IGND
Dropout Voltage, Note 8
Ground Pin Current
IOUT = 100mA
270
300
500
mV
VEN ≥ 2.0V, IOUT = 100µA
20
30
µA
VEN ≥ 2.0V, IOUT = 50mA
0.5
0.8
mA
VEN ≥ 2.0V, IOUT = 150mA
2.8
VEN ≥ 2.0V, IOUT = 100mA
IGND(SHDN)
ISC
en
Ground Pin in Shutdown
Short Circuit Current
Output Noise
/ERR Output
V/ERR
Low Threshold
High Threshold
VOL
/ERR Output Low Voltage
ILEAK
/ERR Output Leakage
1.5
VEN ≤ 0.6V, VIN = 30V
VOUT = 0V
10Hz to 100kHz, VOUT = 3.0V, CL = 1.0µF
% of VOUT
mV
mA
4.0
5.0
0.1
1
µA
260
350
mA
160
90
mA
mA
µVrms
94
%
95
98
%
VIN = VOUT(nom) – 0.12VOUT, IOL = 200µA
150
250
400
mV
mV
VOH = 30V
0.1
1
2
µA
µA
% of VOUT
Enable Input
VIL
VIH
July 2005
Input Low Voltage
regulator off
Input High Voltage
regulator on
0.6
2.0
3
V
V
MIC5236
MIC5236
Micrel, Inc.
Symbol
Parameter
Conditions
IIN
Enable Input Current
Min
Typ
Max
Units
VEN = 0.6V, regulator off
0.01
1.0
2.0
µA
µA
VEN = 2.0V, regulator on
0.15
1.0
2.0
µA
µA
VEN = 30V, regulator on
0.5
2.5
5.0
µA
µA
Note 1.
Exceeding the absolute maximum rating may damage the device.
Note 2.
The device is not guaranteed to function outside its operating rating.
Note 3:
The absolute maximum positive supply voltage (60V) must be of limited duration (≤100ms) and duty cycle (≤1%). The maximum continuous
supply voltage is 30V.
Note 4:
The maximum allowable power dissipation of any TA (ambient temperature) is PD(max) = (TJ(max) – TA) ÷ θJA. Exceeding the maximum allowable power dissipation will result in excessive die termperature, and the regulator will go into thermal shutdown. The θJA of the MIC5236-x.
xBM (all versions) is 63°C/W, and the MIC5236-x.xBMM (all versions) is 80°C/W, mounted on a PC board (see “Thermal Characteristics” for
further details).
Note 5.
Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
Note 6:
Output voltage temperature coefficient is defined as the worst-case voltage change divided by the total temperature range.
Note 7:
Regulation is measured at constant junction temperature using pulse testing with a low duty-cycle. Changes in output voltage due to heating
effects are covered by the specification for thermal regulation.
Note 8:
Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1.0V
differential.
MIC5236
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July 2005
MIC5236
Micrel, Inc.
Typical Characteristics
OUTPUT VOLTAGE (V)
200
0
VOUT = 98% of Nominal VOUT
40
120
80
160
2.0
ILOAD = 150mA
1.5
ILOAD = 100mA
1.0
1.5
MIC5236-3.0
0
2.5
200
25
MIC5236-3.0
GROUND PIN CURRENT (µA)
GROUND PIN CURRENT (mA)
Ground Current
vs. Output Current
3
VIN = 4V
2
1
0
VIN = 10V
0
20 40 60 80 100 120 140 160
20
GROUND CURRENT (mA)
60
50
40
1mA 100µA
30
20
10
0
0
GROUND CURRENT (mA)
4
10µA
1
2
3
4
5
6
7
200
100
MIC5236-3.0
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
5
VIN = 10V
5
0
MIC5236-3.0
0
100
200
300
400
0.08
VIN = 4V
ILOAD = 10mA
0.04
0.02
MIC5236-3.0
MIC5236-3.0
4
ILOAD = 150mA
3
VOUT = 3V
2
1
0
500
ILOAD = 100µA
0
1
2
3
4
5
6
7
1.2
20 40 60 80 100 120
Ground Current
vs. Temperature
1.0
0.8
VIN = 4V
0.6
ILOAD = 75mA
0.4
0.2
MIC5236-3.0
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
TEMPERATURE (°C)
Ground Current
vs. Temperature
Output Voltage
vs. Temperature
Short Circuit Current
vs. Temperature
VIN = 4V
ILOAD = 150mA
2
1
MIC5236-3.0
0
-40 -20 0
20 40 60 80 100 120
TEMPERATURE (°C)
3.015
3.010
MIC5236-3.0
3.005
VIN = 4V
ILOAD = 150mA
3.000
2.995
2.990
2.985
-40 -20 0
20 40 60 80 100 120
TEMPERATURE (°C)
5
8
SUPPLY VOLTAGE (V)
Ground Current
vs. Temperature
0.06
Ground Current
vs. Supply Voltage
SUPPLY VOLTAGE (V)
3
July 2005
4.0
VIN = 4V
0
-40 -20 0
8
VOLTAGE OUTPUT (V)
GROUND PIN CURRENT (µA)
ILOAD = 10mA
70
3.5
10
0.10
MIC5236-3.0
80
3.0
ILOAD = 150mA
300
OUTPUT CURRENT (µA)
Ground Current
vs. Supply Voltage
90
2.5
400
Ground Pin Current
vs. Output Current
15
OUTPUT CURRENT (mA)
100
2.0
500
SUPPLY VOLTAGE (V)
OUTPUT CURRENT (mA)
4
MIC5236-3.0
GROUND CURRENT (mA)
100
ILOAD = 50mA
GROUND CURRENT (mA)
300
Dropout Voltage
vs. Temperature
600
ILOAD = 10mA
3.0
SHORT CIRCUIT CURRENT (mA)
DROPOUT VOLTAGE (mV)
400
Dropout Characteristics
3.5
DROPOUT VOLTAGE (mV)
Dropout Voltage
vs. Output Current
285
280
275
270
VOUT = 0V
265
260
255
-40 -20 0
MIC5236-3.0
20 40 60 80 100 120
TEMPERATURE (°C)
MIC5236
MIC5236
Micrel, Inc.
Line Regulation
41
MIC5236-3.0
3.010
ILOAD = 10mA
3.006
3.004
3.002
0
5
10
15
20
25
30
35
REVERSE CURRENT (µA)
Input Current
3.0
40
20
50
-20
-10
0
INPUT VOLTAGE (V)
10
2.5
2.0
1.5
Note 10
-40°C
30
+25°C
20
10
+85°C
10
15
20
5
EXTERNAL VOLTAGE (V)
MIC5236
OUT
EN GND
MIC5236
2.0
1.5
1.0
0.5
MIC5236-3.0
0
1.25
MIC5236-3.0
VIN = 2.7V
VOUT =2.62V
No Load
0.5
0
0
70
60
0.5
1.0
1.5
SINK CURRENT (mA)
100
200
300
400
CURRENT LIMIT (mA)
Dropout Induced
Error Flag
2.0
1.00
Current Limit Induced
Error Flag
VIN = 6V
VOUT = 2.03V
RL = 6Ω
0.75
0.50
0.25
MIC5236-3.0
0
0
0.5 1.0 1.5 2.0 2.5
SINK CURRENT (mA)
3.0
Reverse Current
(Grounded Input)
Note 11
50
-40°C
40
+25°C
30
20
10
0
0
+85°C
10
15
20
5
EXTERNAL VOLTAGE (V)
Note 10
IN
2.5
0
20 40 60 80 100 120
1.0
Reverse Current
(Open Input)
40
0
0
OUTPUT-LOW VOLTAGE (V)
MIC5236-3.0
60
60
37
3.0
TEMPERATURE (°C)
VE N = 5V
80 R = 30Ω
L
0
-30
38
REVERSE CURRENT (µA)
INPUT CURRENT (mA)
100
39
36
-40 -20 0
INPUT VOLTAGE (V)
120
OUTPUT VOLTAGE (V)
3.012
40
Current Limit
vs. Output Voltage
3.5
MIC5236-3.0
3.014
3.008
Overvoltage Threshold
vs. Temperature
OUTPUT-LOW VOLTAGE (V)
3.016
INPUT VOLTAGE (V)
VOLTAGE OUTPUT (V)
3.018
Note 11
Reverse�
Current
MIC5236
IN
EN
OUT
Reverse�
Current
GND
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July 2005
MIC5236
Micrel, Inc.
Functional Characteristics
Load
Transient Response
VIN = 5V
IL = 10mA
TIME (250µs/div.)
July 2005
VIN = 4V
VOUT = 3V
COUT = 15µF
ESR = 200mΩ
IOUT
(100mA/div.)
VEN
(5V/div.)
VOUT
(100mV/div.)
VOUT
(2V/div.)
Enable
Transient Response
TIME (250µs/div.)
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MIC5236
MIC5236
Micrel, Inc.
Functional Diagram
IN
OUT
EN
RFB1
Error
Amplifier
RFB2
RFB3
ERR
VREF
1.23V
Error
Comparator
MIC5236-x.x
GND
MIC5236
8
July 2005
MIC5236
Micrel, Inc.
Application Information
Error Detection Comparator Output
The ERR pin is an open collector output which goes low when
the output voltage drops 5% below it’s internally programmed
level. It senses conditions such as excessive load (current
limit), low input voltage, and over temperature conditions.
Once the part is disabled via the enable input, the error flag
output is not valid. Overvoltage conditions are not reflected
in the error flag output. The error flag output is also not valid
for input voltages less than 2.3V.
The error output has a low voltage of 400mV at a current of
200µA. In order to minimize the drain on the source used
for the pull-up, a value of 200k to 1MΩ is suggested for the
error flag pull-up. This will guarantee a maximum low voltage
of 0.4V for a 30V pull-up potential. An unused error flag can
be left unconnected.
The MIC5236 provides all of the advantages of the MIC2950:
wide input voltage range, load dump (positive transients up
to 60V), and reversed-battery protection, with the added advantages of reduced quiescent current and smaller package.
Additionally, when disabled, quiescent current is reduced to
0.1µA.
Enable
A low on the enable pin disables the part, forcing the quiescent current to less than 0.1µA. Thermal shutdown and the
error flag are not functional while the device is disabled. The
maximum enable bias current is 2µA for a 2.0V input. An open
collector pull-up resistor tied to the input voltage should be
set low enough to maintain 2V on the enable input. Figure 1
shows an open collector output driving the enable pin through
a 200k pull-up resistor tied to the input voltage.
In order to avoid output oscillations, slow transitions from low
to high should be avoided.
200k
VIN
5V
EN
4.75V
0V
VALID ERROR
Error
Output
VERR
MIC5236
IN
OUT
200k
Output
Voltage
NOT
VALID
NOT
VALID
VOUT
ERR
Input
Voltage
COUT
GND
SHUTDOWN
ENABLE
5V
1.3V
0V
Figure 3. Error Output Timing
Reverse Current Protection
The MIC5236 is designed to limit the reverse current flow
from output to input in the event that the MIC5236 output
has been tied to the output of another power supply. See
the graphs detailing the reverse current flow with the input
grounded and open.
Thermal Shutdown
The MIC5236 has integrated thermal protection. This feature
is only for protection purposes. The device should never be
intentionally operated near this temperature as this may
have detrimental effects on the life of the device. The thermal shutdown may become inactive while the enable input
is transitioning a high to a low. When disabling the device
via the enable pin, transition from a high to low quickly. This
will insure that the output remains disabled in the event of a
thermal shutdown.
Current Limit
Figure 4 displays a method for reducing the steady state
short circuit current. The duration that the supply delivers
current is set by the time required for the error flag output
to discharge the 4.7µF capacitor tied to the enable pin. The
off time is set by the 200K resistor as it recharges the 4.7µF
capacitor, enabling the regulator. This circuit reduces the
short circuit current from 280mA to 15mA while allowing for
regulator restart once the short is removed.
Figure 1. Remote Enable
OUTPUT CAPACITOR ESR (Ω)
Input Capacitor
An input capacitor may be required when the device is not
near the source power supply or when supplied by a battery. Small, surface mount, ceramic capacitors can be used
for bypassing. Larger values may be required if the source
supply has high ripple.
Output Capacitor
The MIC5236 has been designed to minimize the effect of the
output capacitor ESR on the closed loop stability. As a result,
ceramic or film capacitors can be used at the output. Figure 2
displays a range of ESR values for a 10µF capacitor. Virtually
any 10µF capacitor with an ESR less than 3.4Ω is sufficient
for stability over the entire input voltage range. Stability can
also be maintained throughout the specified load and line
conditions with 1µF film or ceramic capacitors.
5
4
3
Stable Region
2
1
0
TJ = 25°C
VOUT = 10µF
5
10
15
20
25
30
INPUT VOLTAGE (V)
Figure 2. Output Capacitor ESR
July 2005
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MIC5236
MIC5236
Micrel, Inc.
which is typically 75°C/W. θCA is reduced because pins 5
through 8 can now be soldered directly to a ground plane
which significantly reduces the case-to-sink thermal resistance
and sink to ambient thermal resistance.
Low-dropout linear regulators from Micrel are rated to a
maximum junction temperature of 125°C. It is important not to
exceed this maximum junction temperature during operation
of the device. To prevent this maximum junction temperature
from being exceeded, the appropriate ground plane heat sink
must be used.
1N4148
200k
VOUT
ERR
EN
COUT
GND
4.7µF
SHUTDOWN
ENABLE
Figure 4. Remote Enable with Short-Circuit
Current Foldback
900
COPPER AREA (mm2)
800
Thermal Characteristics
The MIC5236 is a high input voltage device, intended to
provide 150mA of continuous output current in two very small
profile packages. The power SOIC-8 and power MSOP-8 allow the device to dissipate about 50% more power than their
standard equivalents.
One of the secrets of the MIC5236’s performance is its power
SO-8 package featuring half the thermal resistance of a
standard SO-8 package. Lower thermal resistance means
more output current or higher input voltage for a given package size.
Lower thermal resistance is achieved by joining the four
ground leads with the die attach paddle to create a singlepiece electrical and thermal conductor. This concept has
been used by MOSFET manufacturers for years, proving
very reliable and cost effective for the user.
Thermal resistance consists of two main elements, θJC (junction-to-case thermal resistance) and θCA (case-to-ambient
thermal resistance). See Figure 5. θJC is the resistance from
the die to the leads of the package. θCA is the resistance
from the leads to the ambient air and it includes θCS (caseto-sink thermal resistance) and θSA (sink-to-ambient thermal
resistance).
400
300
200
100
0.25 0.50 0.75 1.00 1.25 1.50
POWER DISSIPATION (W)
Figure 6 shows copper area versus power dissipation with
each trace corresponding to a different temperature rise
above ambient.
From these curves, the minimum area of copper necessary for
the part to operate safely can be determined. The maximum
allowable temperature rise must be calculated to determine
operation along which curve.
ΔT = TJ(max) – TA(max)
TJ(max) = 125°C
TA(max) = maximum ambient operating temperature
For example, the maximum ambient temperature is 50°C,
the ΔT is determined as follows:
ΔT = 125°C – 50°C
ΔT = 75°C
Using Figure 6, the minimum amount of required copper can
be determined based on the required power dissipation. Power
dissipation in a linear regulator is calculated as follows:
PD = (VIN – VOUT) IOUT + VIN · IGND
If we use a 3V output device and a 28V input at moderate
output current of 25mA, then our power dissipation is as
follows:
PD = (28V – 3V) × 25mA + 28V × 250µA
PD = 625mW + 7mW
PD = 632mW
From Figure 6, the minimum amount of copper required to
operate this application at a ΔT of 75°C is 25mm2.
Quick Method
Determine the power dissipation requirements for the design
along with the maximum ambient temperature at which the
device will be operated. Refer to Figure 7, which shows safe
operating curves for three different ambient temperatures:
qJA
ground plane
heat sink area
AMBIENT
printed circuit board
Figure 5. Thermal Resistance
Using the power SOIC-8 reduces the θJC dramatically and
allows the user to reduce θCA. The total thermal resistance,
θJA (junction-to-ambient thermal resistance) is the limiting
factor in calculating the maximum power dissipation capability of the device. Typically, the power SOIC-8 has a θJC of
20°C/W, this is significantly lower than the standard SOIC-8
MIC5236
500
Figure 6. Copper Area vs. Power-SOIC
Power Dissipation (∆TJA)
SOP-8
qCA
600
0
0
Power SOIC-8 Thermal Characteristics
qJC
700
100°C
VIN
5V
VERR
MIC5236
IN
OUT
40°C
50°C
55°C
65°C
75°C
85°C
200k
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July 2005
MIC5236
Micrel, Inc.
25°C, 50°C and 85°C. From these curves, the minimum
amount of copper can be determined by knowing the maximum power dissipation required. If the maximum ambient
temperature is 50°C and the power dissipation is as above,
632mW, the curve in Figure 7 shows that the required area
of copper is 25mm2.
The θJA of this package is ideally 63°C/W, but it will vary
depending upon the availability of copper ground plane to
which it is attached.
900
COPPER AREA (mm2)
800
COPPER AREA (mm2)
TJ = 125°C
700
85°C
50°C 25°C
50°C 25°C
500
400
300
200
100
0
0
0.25 0.50 0.75 1.00 1.25 1.50
POWER DISSIPATION (W)
Figure 9. Copper Area vs. Power-MSOP
Power Dissipation (TA)
600
500
400
Power MSOP-8 Thermal Characteristics
300
The power-MSOP-8 package follows the same idea as the
power-SO-8 package, using four ground leads with the die
attach paddle to create a single-piece electrical and thermal
conductor, reducing thermal resistance and increasing power
dissipation capability.
Quick Method
Determine the power dissipation requirements for the design
along with the maximum ambient temperature at which the
device will be operated. Refer to Figure 9, which shows safe
operating curves for three different ambient temperatures,
25°C, 50°C, and 85°C. From these curves, the minimum
amount of copper can be determined by knowing the maximum power dissipation required. If the maximum ambient
temperature is 50°C, and the power dissipation is 639mW,
the curve in Figure 9 shows that the required area of copper
is 110mm2,when using the power MSOP-8.
Adjustable Regulator Application
200
100
0
0
0.25 0.50 0.75 1.00 1.25 1.50
POWER DISSIPATION (W)
100°C
700
40°C
50°C
55°C
65°C
75°C
85°C
Figure 7. Copper Area vs. Power-SOIC
Power Dissipation (TA)
COPPER AREA (mm2)
85°C
600
900
800
T = 125°C
J
700
600
500
400
300
200
100
0
0
0.25 0.50 0.75 1.00 1.25 1.50
POWER DISSIPATION (W)
MIC5236BM/MM
Figure 8. Copper Area vs. Power-MSOP
Power Dissipation (∆TJA)
VIN
2
4
The same method of determining the heat sink area used
for the power-SOIC-8 can be applied directly to the powerMSOP-8. The same two curves showing power dissipation
versus copper area are reproduced for the power-MSOP-8
and they can be applied identically, see Figures 8 and 9.
IN
OUT
EN
ADJ
GND
5-8
3
1
VOUT
R1
R2
1µF
Figure 10. Adjustable Voltage Application
The MIC5236BM/MM can be adjusted from 1.24V to 20V by
using two external resistors (Figure 10). The resistors set the
output voltage based on the following equation:
R1
VOUT = VREF (1 +
)
R2
Where VREF = 1.23V.
July 2005
11
MIC5236
MIC5236
Micrel, Inc.
Package Information
0.026 (0.65)
MAX)
PIN 1
0.157 (3.99)
0.150 (3.81)
DIMENSIONS:
INCHES (MM)
0.020 (0.51)
0.013 (0.33)
0.050 (1.27)
TYP
0.064 (1.63)
0.045 (1.14)
45°
0.0098 (0.249)
0.0040 (0.102)
0.197 (5.0)
0.189 (4.8)
0°–8°
0.010 (0.25)
0.007 (0.18)
0.050 (1.27)
0.016 (0.40)
SEATING
PLANE
0.244 (6.20)
0.228 (5.79)
8-Pin SOIC (M)
0.122 (3.10)
0.112 (2.84)
0.199 (5.05)
0.187 (4.74)
DIMENSIONS:
INCH (MM)
0.120 (3.05)
0.116 (2.95)
0.036 (0.90)
0.032 (0.81)
0.043 (1.09)
0.038 (0.97)
0.012 (0.30) R
0.012 (0.03)
0.0256 (0.65) TYP
0.008 (0.20)
0.004 (0.10)
5° MAX
0° MIN
0.007 (0.18)
0.005 (0.13)
0.012 (0.03) R
0.039 (0.99)
0.035 (0.89)
0.021 (0.53)
8-Pin MSOP (MM)
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 specifications at any time without notification 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 significant 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, Inc.
MIC5236
12
July 2005