MIC49150-1.2BMMTR [MICROCHIP]
Fixed Positive LDO Regulator, 1.2V, 0.5V Dropout, PDSO8, MSOP-8;
| 型号： | MIC49150-1.2BMMTR |
| 厂家： | 
MICROCHIP |
| 描述： | Fixed Positive LDO Regulator, 1.2V, 0.5V Dropout, PDSO8, MSOP-8 光电二极管 输出元件 调节器 |
| 文件： | 总12页 (文件大小：795K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MIC49150
1.5A Low Voltage LDO Regulator w/Dual Input Voltages
General Description
Features
The MIC49150 is a high-bandwidth, low-dropout, 1.5A volt-
age regulator ideal for powering core voltages of low-power
microprocessors. The MIC49150 implements a dual supply
configuration allowing for very low output impedance and
very fast transient response.
• Input Voltage Range:
V : 1.4V to 6.5V
IN
V
: 3.0V to 6.5V
BIAS
• Stable with 1µF ceramic capacitor
• ±1% initial tolerance
• Maximum dropout voltage (V –V
) of 500mV over
The MIC49150 requires a bias input supply and a main input
supply,allowingforultra-lowinputvoltagesonthemainsupply
rail. The input supply operates from 1.4V to 6.5V and the bias
supply requires between 3V and 6.5V for proper operation.
The MIC49150 offers fixed output voltages from 0.9V to 1.8V
and adjustable output voltages down to 0.9V.
IN
OUT
temperature
• Adjustable output voltage down to 0.9V
• Ultra fast transient response (Up to 10MHz bandwidth)
• Excellent line and load regulation specifications
• Logic controlled shutdown option
• Thermal shutdown and current limit protection
• Power MSOP-8 and S-Pak packages
The MIC49150 requires a minimum of output capacitance for
stability, working optimally with small ceramic capacitors.
• Junction temperature range: –40°C to 125°C
The MIC49150 is available in an 8-pin power MSOP pack-
age and a 5-pin S-Pak. Its operating temperature range is
–40°C to +125°C.
Applications
• Graphics processors
• PC add-in cards
• Microprocessor core voltage supply
• Low voltage digital ICs
• High efficiency linear power supplies
• SMPS post regulators
Typical Application
Load Transient Response
MIC49150BR
VIN = 1.8V
VOUT = 1.0V
IN
OUT
R1
R2
V
BIAS = 3.3V
CBIAS = 1µ
BIAS
ADJ
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1V
COUT
Ceramic
= 1µF
F
COUT = 1µF ceramic
GND
Ceramic
CIN = 1µ
F
Ceramic
Low Voltage,
Fast Transient Response Regulator
TIME (10µs/div.)
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
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MIC49150
Micrel
Ordering Information
Part Number
Output
Voltage Junction Temp. Range
Package
Current
Standard
Pb-Free /
RoHS Compliant
MIC49150-0.9BMM MIC49150-0.9YMM
MIC49150-1.2BMM MIC49150-1.2YMM
MIC49150-1.5BMM MIC49150-1.5YMM
MIC49150-1.8BMM MIC49150-1.8YMM
1.5A
1.5A
1.5A
1.5A
1.5A
1.5A
1.5A
1.5A
1.5A
1.5A
0.9V
1.2V
1.5V
1.8V
Adj.
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
Power MSOP-8
Power MSOP-8
Power MSOP-8
Power MSOP-8
Power MSOP-8
S-Pak-5
MIC49150BMM
MIC49150-0.9BR
MIC49150-1.2BR
MIC49150-1.5BR
MIC49150-1.8BR
MIC49150BR
MIC49150YMM
MIC49150-0.9WR*
MIC49150-1.2WR*
MIC49150-1.5WR*
MIC49150-1.8WR*
MIC49150WR*
0.9V
1.2V
1.5V
1.8V
Adj.
S-Pak-5
S-Pak-5
S-Pak-5
S-Pak-5
* RoHS compliant with "high-melting solder" exemption.
Pin Configuration
GN
GN
GN
GN
1
2
3
4
8
7
6
5
EN/ADJ.
VBIAS
5
4
3
2
1
VOUT
VIN
GND
VBIAS
EN/ADJ.
VIN
VOUT
5-Lead S-Pak (R)
Power MSOP-8 (MM)
Pin Description
MIC49150
MIC49150
MSOP8
S-Pak
Pin Name
Pin Function
1
1
Enable
Enable (Input): CMOS compatible input. Logic high = enable, logic low =
shutdown.
ADJ.
VIN
Adjustable regulator feedback input. Connect to resistor voltage divider.
Input voltage which supplies current to the output power device.
Regulator Output.
3
4
2
4
5
2
VOUT
VBIAS
Input Bias Voltage for powering all circuitry on the regulator with the excep-
tion of the output power device.
5/6/7/8
3
GND
Ground (TAB is connected to ground on S-Pak).
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MIC49150
Micrel
Absolute Maximum Ratings(1)
Operating Ratings(2)
Supply Voltage (V )........................................................8V
Supply Voltage (V ).........................................1.4V to 6.5V
IN
IN
Bias Supply Voltage (V
) ............................................8V
Bias Supply Voltage (V
) ................................3V to 6.5V
BIAS
BIAS
Enable Input Voltage (V ) .............................................8V
Enable Input Voltage (V ) .................................0V to 6.5V
EN
EN
Power Dissipation..................................... Internally Limited
Junction Temperature Range ..............–40°C ≤T ≤ +125°C
J
(3)
ESD Rating ............................................................... 2kV
Package Thermal Resistance
....................................................................
MSOP-8 (θ )
80°C/W
JA
S-PAK(θ ) ...........................................................2°C/W
JC
Electrical Characteristics(4)
TA = 25°C with VBIAS = VOUT +2.1V; VIN = VOUT + 1V, unless otherwise specified; bold values indicate –40°C<TJ<+125°C(5)
Parameter
Conditions
Min
Typ
Max
Units
Output Voltage Accuracy
At 25°C
Over temperature range
–1
–2
+1
+2
%
%
Line Regulation
Load Regulation
VIN = VOUT +1V to 6.5V
IL = 0mA to 1.5A
–0.1
0.01
0.2
+0.1
%/V
1
1.5
%
%
Dropout Voltage (VIN - VOUT
)
IL = 750mA
IL = 1.5A
130
280
200
300
400
500
mV
mV
mV
mV
Dropout Voltage (VBIAS - VOUT
Note 5
)
IL = 750mA
IL = 1.5A
1.3
1.65
V
V
V
1.9
2.1
Ground Pin Current Note 6
IL = 0mA
IL = 1.5A
15
15
mA
mA
mA
25
30
Ground Pin Current in Shutdown
Current thru VBIAS
VEN ≤ 0.6V, (IBIAS + ICC) Note 7
0.5
9
1
2
µA
µA
IL = 0mA
15
25
mA
mA
mA
IL = 1.5A
32
Current Limit
MIC49150
1.6
2.3
3.5
4
A
A
Enable Input (Note 7)
Enable Input Threshold
(Fixed Voltage only)
Regulator enable
Regulator shutdown
1.6
V
V
0.6
Enable Pin Input Current
Reference
Independent of state
0.1
0.9
1
µA
Reference Voltage
0.891
0.882
0.909
0.918
V
V
Notes
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
4. Specification for packaged product only.
5. For VOUT ≤1V, VBIAS dropout specification does not apply due to a minimum 3V VBIAS input.
6. IGND = IBIAS + (IIN – IOUT). At high loads, input current on VIN will be less than the output current, due to drive current being supplied by VBIAS
.
7. Fixed output voltage versions only.
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Functional Diagram
VBIAS
VIN
Ilimit
VEN ADJ
/
Fixed
Bandgap
Enable
Adj.
VOUT
VIN Open
Circuit
R1
R2
Fixed
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MIC49150
Micrel
Typical Characteristics
P ower S upply R ejection R atio
P ower S upply R ejection R atio
(B ias S uppl
Dropout Voltage
(Input S uppl
(Input S uppl
y
)
y
)
y)
80
70
60
50
40
30
20
10
0
80
70
60
50
40
30
20
10
0
300
250
200
150
100
50
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1.0V
IOUT = 1.5A
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1.0V
IOUT = 1.5A
VBIAS = 5V
VOUT = 1.0V
C OUT = 1µF ceramic
C OUT = 1µF ceramic
0
0.01
0.1
1
10
100 1000
0.01
0.1
1
10
100 1000
FREQUENCY (kHz)
FREQUENCY (kHz)
OUTPUT CURRENT (mA)
Dropout Voltage
(B ias S upply)
Dropout Voltage
vs . Temperature
(Input S upply)
Dropout Voltage
vs . Temperature
(B ias S upply)
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
400
350
300
250
200
150
100
50
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
VBIAS = 5V
IOUT = 1.5A
VOUT = 1.5V
VIN = 2.5V
IOUT = 1.5A
VOUT = 1.5V
VIN = 2.5V
VOUT = 1.5V
0
-40 -20
0
20 40 60 80 100 120
-40 -20
0
20 40 60 80 100 120
TEMPERATURE(°C)
TEMPERATURE(°C)
OUTPUT CURRENT (mA)
Dropout C haracteris tics
(Input Voltage)
Dropout C haracteris tics
(B ias Voltage)
L oad R egulation
1.505
1.504
1.503
1.502
1.501
1.500
1.499
1.498
1.497
1.496
1.495
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
IOUT = 10mA
IOUT = 10mA
IOUT = 1.5A
IOUT = 1.5A
VBIAS = 5V
VIN = 2.5V
VBIAS = 5V
VOUT = 1.5V
VIN = 2.5V
VOUT = 1.5V
0
0.5
1
1.5
2
2.5
0
1
2
3
4
5
6
7
INPUT VOLTAGE (V)
BIAS VOLTAGE (V)
OUTPUT CURRENT (mA)
Maximum B ias C urrent
vs . B ias Voltage
Maximum B ias C urrent
vs . Temperature
B ias C urrent
vs . Temperature
45
40
35
30
300
250
200
150
100
50
300
250
200
150
100
50
VIN = 2.5V
VOUT = 1.5V
VBIAS = 5V
VADJ = 0V
IOUT = 1.5A
VIN = 2.5V
IOUT = 750mA
VBIAS = 5V
VADJ = 0V
VIN = 2.5V
25
20
15
10
5
IOUT = 1500mA
IOUT = 100mA
*Note: Maximum bias current is bias
current with input in dropout
IOUT = 10mA
20 40 60 80 100 120
0
0
0
-40 -20
0
-40 -20
0
20 40 60 80 100 120
3
3.5
4
4.5
5
5.5
6
6.5
TEMPERATURE (°C)
TEMPERATURE(°C)
BIAS VOLTAGE (V)
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MIC49150
Micrel
B ias C urrent
vs . Output C urrent
G round C urrent
vs . B ias Voltage
B ias C urrent
vs . B ias Voltage
50
40
30
20
10
0
14
12
10
8
14
12
10
8
IBIAS
VBIAS = 5V
VIN = 2.5V
VOUT = 1.5V
IBIAS
6
6
IOUT = 100mA
VIN = 2.5V
VOUT = 1.5V
IOUT = 0mA
VIN = 2.5V
VOUT = 1.5V
4
4
2
2
0
0
3
3.5
4
4.5
5
5.5
6
6.5
3
3.5
4
4.5
5
5.5
6
6.5
BIAS VOLTAGE (V)
BIAS VOLTAGE (V)
OUTPUT CURRENT (mA)
B ias C urrent
vs . B ias Voltage
B ias C urrent
vs . B ias Voltage
B ias C urrent
vs . Input Voltage
20
50
40
30
20
10
0
50
40
30
20
10
0
VBIAS = 5V
VOUT = 1.5V
IOUT = 750mA
VIN = 2.5V
VOUT = 1.5V
18
16
14
12
10
8
IBIAS
IOUT = 100mA
IBIAS
IOUT = 0mA
IOUT = 1500mA
VIN = 2.5V
VOUT = 1.5V
6
4
2
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
3
3.5
4
4.5
5
5.5
6
6.5
INPUT VOLTAGE (V)
BIAS VOLTAGE (V)
BIAS VOLTAGE (V)
B ias C urrent
vs . Input Voltage
R eference Voltage
vs . Input Voltage
R eference Voltage
vs . B ias Voltage
0.901
0.900
0.899
0.901
0.900
0.899
300
VBIAS = 5V
250 VOUT = 1.5V
1500mA
VBIAS = 5V
VIN = 2.5V
200
750mA
150
100
50
0
0
0.5
1
1.5
2
2.5
1.4
2.4
3.4
4.4
5.4
6.4
3
3.5
4
4.5
5
5.5
6
6.5
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
BIAS VOLTAGE (V)
Output Voltage
vs . Temperature
S hort C ircuit C urrent
vs . Temperature
E nable Thres hold
vs . B ias Voltage
1.55
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
3.0
2.5
2.0
1.5
1.0
0.5
0
VBIAS = 5V
VIN = 2.5V
1.54
1.53
1.52
1.51
1.50
1.49
1.48
1.47
1.46
1.45
ON
OFF
VBIAS = 5V
VIN = 2.5V
VOUT = 0V
VIN = 2.5V
0
3
-40 -20
0
20 40 60 80 100 120
3.5
4
4.5
5
5.5
6
6.5
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
BIAS VOLTAGE (V)
TEMPERATURE (°C)
M9999-082505-B
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August 2005
MIC49150
Micrel
E nable Thres hold
vs . Temperature
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
ON
OFF
VBIAS = 5V
VIN = 2.5V
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
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MIC49150
Micrel
Functional Characteristics
Load Transient Response
Bias Voltage
Line Transient Response
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1V
VBIAS = 6.5V
COUT = 1µF ceramic
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1V
COUT = 1µF ceramic
IOUT = 1.5A
TIME (10µs/div.)
TIME (400µs/div.)
Input Voltage
Line Transient Response
VIN = 6.5V
VIN = 1.8V
VBIAS = 3.3V
VOUT = 1V
COUT = 1µF ceramic
IOUT = 1.5A
TIME (400µs/div.)
M9999-082505-B
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August 2005
MIC49150
Micrel
Input Capacitor
Applications Information
An input capacitor of 1µF or greater is recommended when
the device is more than 4" away from the bulk supply capaci-
tance, or when the supply is a battery. Small, surface-mount,
ceramic chip capacitors can be used for the bypassing. The
capacitor should be placed within 1" of the device for optimal
performance. Larger values will help to improve ripple rejec-
tion by bypassing the input to the regulator, further improving
the integrity of the output voltage.
The MIC49150 is an ultra-high performance, low-dropout
linear regulator designed for high current applications requir-
ing fast transient response. The MIC49150 utilizes two input
supplies, significantly reducing dropout voltage, perfect for
low-voltage, DC-to-DC conversion. The MIC49150 requires
a minimum of external components and obtains a bandwidth
of up to 10MHz. As a µCap regulator, the output is tolerant
of virtually any type of capacitor including ceramic type and
tantalum type capacitors.
Thermal Design
The MIC49150 regulator is fully protected from damage due
to fault conditions, offering linear current limiting and thermal
shutdown.
Linear regulators are simple to use. The most complicated
design parameters to consider are thermal characteristics.
Thermal design requires the following application-specific
parameters:
Bias Supply Voltage
• Maximum ambient temperature (T )
V
, requiring relatively light current, provides power to the
A
BIAS
controlportionoftheMIC49150.V
requiresapproximately
• Output current (I
)
BIAS
OUT
33mA for a 1.5A load current. Dropout conditions require
higher currents. Most of the biasing current is used to supply
the base current to the pass transistor. This allows the pass
element to be driven into saturation, reducing the dropout to
300mV at a 1.5A load current. Bypassing on the bias pin is
recommended to improve performance of the regulator dur-
ing line and load transients. Small ceramic capacitors from
• Output voltage (V
)
)
OUT
• Input voltage (V )
IN
• Ground current (I
GND
First,calculatethepowerdissipationoftheregulatorfromthese
numbers and the device parameters from this datasheet.
P = V × I + V
× I
– V
× I
D
IN
IN
BIAS
BIAS
OUT OUT
V
to ground help reduce high frequency noise from being
BIAS
The input current will be less than the output current at high
output currents as the load increases. The bias current is
a sum of base drive and ground current. Ground current
is constant over load current. Then the heat sink thermal
resistance is determined with this formula:
injected into the control circuitry from the bias rail and are
good design practice. Good bypass techniques typically in-
cludeonelargercapacitorsuchasa1µFceramicandsmaller
valued capacitors such as 0.01µF or 0.001µF in parallel with
that larger capacitor to decouple the bias supply. The V
BIAS
T
– T
A
input voltage must be 1.6V above the output voltage with a
J(MAX)
–
SA
JC
CS
minimum V
input voltage of 3 volts.
BIAS
P
D
Input Supply Voltage
The heat sink may be significantly reduced in applications
where the maximum input voltage is known and 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 the MIC49150 allow significant reductions in regulator
power dissipation and the associated heat sink without com-
promising 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 specification.
V
provides the high current to the collector of the pass
IN
transistor. The minimum input voltage is 1.4V, allowing con-
version from low voltage supplies.
Output Capacitor
The MIC49150 requires a minimum of output capacitance
to maintain stability. However, proper capacitor selection
is important to ensure desired transient response. The
MIC49150 is specifically designed to be stable with virtually
any capacitance value and ESR. A1µF ceramic chip capaci-
tor should satisfy most applications. Output capacitance can
be increased without bound. See “Typical Characteristic” for
examples of load transient response.
Minimum Load Current
X7Rdielectricceramiccapacitorsarerecommendedbecause
oftheirtemperatureperformance.X7R-typecapacitorschange
capacitance by 15% over their operating temperature range
and are the most stable type of ceramic capacitors. Z5U
and Y5V dielectric capacitors change value by as much as
50% and 60% respectively over their operating temperature
ranges. To use a ceramic chip capacitor with Y5V dielectric,
the value must be much higher than an X7R ceramic or a
tantalumcapacitortoensurethesamecapacitancevalueover
theoperatingtemperaturerange.Tantalumcapacitorshavea
very stable dielectric (10% over their operating temperature
range) and can also be used with this device.
The MIC49150, unlike most other high current regulators,
does not require a minimum load to maintain output voltage
regulation.
Power MSOP-8 Thermal Characteristics
One of the secrets of the MIC49150’s performance is its
powerMSOP-8packagefeaturinghalfthethermalresistance
of a standard MSOP-8 package. Lower thermal resistance
means more output current or higher input voltage for a given
package size.
August 2005
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M9999-082505-B
MIC49150
Micrel
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Lower thermal resistance is achieved by joining the four
ground leads with the die attach paddle to create a single-
piece 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, θ (junc-
JC
tion-to-case thermal resistance) and θ (case-to-ambient
CA
thermal resistance). See Figure 1. θ is the resistance from
JC
the die to the leads of the package. θ is the resistance
CA
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from the leads to the ambient air and it includes θ (case-
CS
to-sink thermal resistance) and θ (sink-to-ambient thermal
resistance).
SA
Figure 2. Copper Area vs. Power-MSOP
Power Dissipation (∆T
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)
Using the power MSOP-8 reduces the θ dramatically and
JA
JC
allows the user to reduce θ . The total thermal resistance,
CA
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θ
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factor in calculating the maximum power dissipation capabil-
ity of the device. Typically, the power MSOP-8 has a θ of
JA
80°C/W, this is significantly lower than the standard MSOP-8
which is typically 160°C/W. θ is reduced because pins 5
CA
through 8 can now be soldered directly to a ground plane
whichsignificantlyreducesthecase-to-sinkthermalresistance
and sink to ambient thermal resistance.
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Low-dropout linear regulators from Micrel are rated to a
maximumjunctiontemperatureof125°C.Itisimportantnotto
exceed this maximum junction temperature during operation
of the device. To prevent this maximum junction temperature
frombeingexceeded, theappropriategroundplaneheatsink
must be used.
Figure 3. Copper Area vs. Power-MSOP
Power Dissipation (T )
A
ΔT = T
– T
A(max)
J(max)
T
T
= 125°C
J(max)
= maximum ambient operating temperature
A(max)
MSOP-8
For example, the maximum ambient temperature is 50°C,
the ΔT is determined as follows:
ΔT = 125°C – 50°C
ΔT = 75°C
�
JA
Using Figure 2, the minimum amount of required copper can
bedeterminedbasedontherequiredpowerdissipation.Power
dissipation in a linear regulator is calculated as follows:
ground plane
heat sink area
�
�
CA
JC
AMBIENT
P = V × I + V
× I
– V
× I
D
IN
IN
BIAS
BIAS
OUT OUT
printed circuit board
Using a typical application of 750mA output current, 1.2V
output voltage, 1.8V input voltage and 3.3V bias voltage, the
power dissipation is as follows:
Figure 1. Thermal Resistance
Figure 2 shows copper area versus power dissipation with
each trace corresponding to a different temperature rise
above ambient.
P = (1.8V) × (730mA) + 3.3V(30mA) – 1.2V(750mA)
D
At full current, a small percentage of the output current is
supplied from the bias supply, therefore the input current is
less than the output current.
Fromthesecurves,theminimumareaofcoppernecessaryfor
the part to operate safely can be determined. The maximum
allowable temperature rise must be calculated to determine
operation along which curve.
P = 513mW
D
From Figure 2, the minimum current of copper required to op-
2
erate this application at a ∆T of 75°C is less than 100mm .
M9999-082505-B
10
August 2005
MIC49150
Micrel
Quick Method
Enable
Determine the power dissipation requirements for the design
along with the maximum ambient temperature at which the
device will be operated. Refer to Figure 3, 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 maxi-
mum power dissipation required. If the maximum ambient
temperature is 50°C and the power dissipation is as above,
513mW, the curve in Figure 3 shows that the required area
ThefixedoutputvoltageversionsoftheMIC49150featurean
active high enable input (EN) that allows on-off control of the
regulator. Current drain reduces to “zero” when the device is
shutdown, with only microamperes of leakage current. The
EN input has TTL/CMOS compatible thresholds for simple
logic interfacing. EN may be directly tied to V and pulled
IN
up to the maximum supply voltage
2
of copper is less than 100mm .
The θ of this package is ideally 80°C/W, but it will vary
JA
depending upon the availability of copper ground plane to
which it is attached.
Adjustable Regulator Design
The MIC49150 adjustable version allows programming the
output voltage anywhere between 0.9Vand 5V. Two resistors
areused.TheresistorvaluebetweenV
andtheadjustpin
OUT
should not exceed 10kΩ. Larger values can cause instability.
The resistor values are calculated by:
V
OUT
R1 R2
– 1
0.9
Where V
is the desired output voltage.
OUT
August 2005
11
M9999-082505-B
MIC49150
Micrel
Package Information
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)
0.007 (0.1
0.005 (0.1
0.012 (0.30) R
0.008 (0.20)
0.004 (0.10)
5 MAX
0 MIN
0.012 (0.3)
0.012 (0.03)
0.039 (0.99)
0.0256 (0.65) TYP
0.035 (0.89)
0.021 (0.53)
8-Lead MSOP (MM)
5-Lead S-Pak (R)
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 Incorporated
M9999-082505-B
12
August 2005
相关型号：
MIC49150-1.2YMMTR
1.2V FIXED POSITIVE LDO REGULATOR, 0.5V DROPOUT, PDSO8, ROHS COMPLIANT, POWER, MSOP-8
MICROCHIP
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