Micrel MIC49150WR 1.5a low voltage ldo regulator w/dual input voltage Datasheet

MIC49150
1.5A Low Voltage LDO Regulator
w/Dual Input Voltages
General Description
Features
The MIC49150 is a high-bandwidth, low-dropout, 1.5A voltage regulator ideal for powering core voltages of lowpower microprocessors. The MIC49150 implements a dual
supply configuration allowing for very low output
impedance and very fast transient response.
The MIC49150 requires a bias input supply and a main
input supply, allowing for ultra-low input voltages on the
main supply 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.
The MIC49150 requires a minimum of output capacitance
for stability, working optimally with small ceramic
capacitors.
The MIC49150 is available in an 8-pin power MSOP package and a 5-pin S-Pak. Its operating temperature range is
–40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
• Input Voltage Range:
– VIN: 1.4V to 6.5V
– VBIAS: 3.0V to 6.5V
• Stable with 1µF ceramic capacitor
• ±1% initial tolerance
• Maximum dropout voltage (VIN–VOUT) of 500mV
over 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
• Junction temperature range: –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
VIN = 1.8V
MIC49150BR
IN
OUT
VOUT = 1.0V
R1
VBIAS = 3.3V
CBIAS = 1µF
Ceramic
BIAS
ADJ
GND
R2 COUT = 1µF
Ceramic
CIN = 1µF
Ceramic
Low Voltage,
Fast Transient Response Regulator
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
November 2006
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M9999-111306
Micrel, Inc.
MIC49150
Ordering Information
Part Number
Output
Current
Voltage
Junction
Temp. Range
Package
MIC49150-0.9YMM
1.5A
0.9V
–40° to +125°C
8-Pin Power MSOP
MIC49150-1.2BMM
MIC49150-1.2YMM
1.5A
1.2V
–40° to +125°C
8-Pin Power MSOP
MIC49150-1.5BMM
MIC49150-1.5YMM
1.5A
1.5V
–40° to +125°C
8-Pin Power MSOP
MIC49150-1.8BMM
MIC49150-1.8YMM
1.5A
1.8V
–40° to +125°C
8-Pin Power MSOP
MIC49150BMM
MIC49150YMM
1.5A
Adj.
–40° to +125°C
8-Pin Power MSOP
MIC49150-0.9BR
MIC49150-0.9WR*
1.5A
0.9V
–40° to +125°C
5-Pin S-PAK
MIC49150-1.2BR
MIC49150-1.2WR*
1.5A
1.2V
–40° to +125°C
5-Pin S-PAK
MIC49150-1.5BR
MIC49150-1.5WR*
1.5A
1.5V
–40° to +125°C
5-Pin S-PAK
MIC49150-1.8BR
MIC49150-1.8WR*
1.5A
1.8V
–40° to +125°C
5-Pin S-PAK
MIC49150BR
MIC49150WR*
1.5A
Adj.
–40° to +125°C
5-Pin S-PAK
Standard
Pb-Free /
RoHS Compliant
MIC49150-0.9BMM
* RoHS Compliant with ‘high-melting solder’ exemption.
EN/ADJ. 1
8 GND
VBIAS 2
7 GND
VIN 3
6 GND
VOUT 4
5 GND
TAB
Pin Configuration
8-Pin Power MSPO (MM)
5
4
3
2
1
VOUT
VIN
GND
VBIAS
EN/ADJ.
5-Pin S-Pak (R)
Pin Description
Pin Number
8-MSOP
Pin Number
1
1
Pin Name
Pin Name
5-SPak
EN
Enable (Input): CMOS compatible input. Logic high = enable,
logic low = shutdown.
ADJ
Adjustable regulator feedback input. Connect to resistor
voltage divider.
Input Bias Voltage for powering all circuitry on the regulator
with the exception of the output power device.
2
2
VBIAS
3
4
VIN
Input voltage which supplies current to the output power
device.
4
5
OUT
Regulator Output.
5/6/7/8
3
GND
Ground (TAB is connected to ground on S-Pak).
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MIC49150
Absolute Maximum Ratings(1)
Operating Ratings(2)
Supply Voltage (VIN) .........................................................8V
Bias Supply Voltage (VBIAS)..............................................8V
Enable Input Voltage (VEN)...............................................8V
Power Dissipation .....................................Internally Limited
ESD Rating(3) .................................................................. 4kV
Supply Voltage (VIN)......................................... 1.4V to 6.5V
Bias Supply Voltage (VBIAS)................................. 3V to 6.5V
Enable Input Voltage (VEN).................................. 0V to 6.5V
Junction Temperature (TJ) ..................–40°C ≤ TJ ≤ +125°C
Package Thermal Resistance
MSOP-8 (θJA).....................................................80°C/W
S-Pak (θJC) ..........................................................2°C/W
Electrical Characteristics(4)
TA = 25°C with VBIAS = VOUT + 2.1V; VIN = VOUT + 1V; bold values indicate –40°C< TJ < +125°C, unless noted(5).
Parameter
Condition
Min
Output Voltage Accuracy
At 25°C
Over temperature range
–1
–2
Line Regulation
VIN = VOUT +1V to 6.5V
–0.1
Load Regulation
Dropout Voltage (VIN - VOUT)
Typ
Max
Units
+1
+2
%
%
0.01
+0.1
%/V
IL = 0mA to 1.5A
0.2
1
1.5
%
%
IL = 750mA
130
IL = 1.5A
280
200
300
400
500
mV
mV
mV
mV
Dropout Voltage (VBIAS - VOUT),
Note 5
IL = 750mA
IL = 1.5A
1.3
1.65
1.9
2.1
V
V
V
Ground Pin Current, Note 6
IL = 0mA
IL = 1.5A
15
15
25
30
mA
mA
mA
Ground Pin Current in
Shutdown
VEN ≤ 0.6V, (IBIAS + ICC), Note 7
0.5
1
2
µA
µA
Current thru VBIAS
IL = 0mA
9
15
25
mA
mA
mA
Current Limit
MIC49150
1.6
3.4
4
A
A
Enable Input Threshold
(Fixed Voltage only)
Regulator enable
Regulator shutdown
1.6
0.6
V
V
Enable Pin Input Current
Independent of state
0.1
1
µA
0.9
0.909
0.918
V
V
32
IL = 1.5A
2.3
Enable Input (Note 7)
Reference
0.891
0.882
Reference Voltage
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, 1.5kΩ 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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MIC49150
Typical Characteristics
0.6
0.4
100
50
1.6
OUTPUT VOLTAGE (V)
0.8
0.6
0.4
VBIAS = 5V
0.2 V
OUT = 1.5V
0.5
1
1.5
2
INPUT VOLTAGE (V)
2.5
BIAS CURRENT (mA)
250
VADJ = 0V
IOUT = 1.5A
VIN = 2.5V
200
150
100
*Note: Maximum bias current is bias
current with input in dropout
3.5
4 4.5 5 5.5 6
BIAS VOLTAGE (V)
November 2006
6.5
1600
1400
1200
1000
800
1.2
1.0
0.8
0.6
0.4
VIN = 2.5V
IOUT = 1.5A
VOUT = 1.5V
0.2
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE(°C)
Load Regulation
1.504
1.2
IOUT = 10mA
1.0
0.8
IOUT = 1.5A
0.6
0.4
VIN = 2.5V
VOUT = 1.5V
0.2
300
1.8
1.6
1.4
1.505
1.4
0
0
Maximum Bias Current
vs. Bias Voltage
3
VBIAS = 5V
IOUT = 1.5A
VOUT = 1. 5V
Dropout Characteristics
(Bias Voltage)
IOUT = 1.5A
50
150
Dropout Characteristics
(Input Voltage)
1.0
300
200
OUTPUT CURRENT (mA)
1.2
0
0
250
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE(°C)
IOUT = 10mA
1.4
2.0
300
1600
1400
1200
800
0
1.6
600
0.2
1000
VIN = 2.5V
VOUT = 1.5V
Dropout Voltage
vs. Temperature
(Bias Supply)
1
2
3
4
5
6
BIAS VOLTAGE (V)
1.503
1.502
1.501
1.500
1.499
1.498
1.497
VBIAS = 5V
VIN = 2.5V
1.496
1.495
7
OUTPUT CURRENT (mA)
Maximum Bias Current
vs. Temperature
45
Bias Current
vs. Temperature
VIN = 2.5V
VOUT = 1.5V
VBIAS = 5V
40
250
200
VBIAS = 5V
VADJ = 0V
VIN = 2.5V
150
100
50
1600
0.8
Dropout Voltage
vs. Temperature
(Input Supply)
1400
1.0
OUTPUT CURRENT (mA)
1200
1.2
0
1000
1000
350
DROPOUT VOLTAGE (mV)
400
1.4
200
DROPOUT VOLTAGE (V)
1.6
0
0.1
1
10
100
FREQUENCY (kHz)
Dropout Voltage
(Bias Supply)
0
OUTPUT VOLTAGE (V)
0
0.01
1000
VBIAS = 5V
VOUT = 1.0V
50
800
0.1
1
10
100
FREQUENCY (kHz)
1.8
BIAS CURRENT (mA)
10
100
600
0
0.01
20
600
10
30
150
400
20
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1.0V
IOUT = 1.5A
COUT = 1µF ceramic
0
30
40
200
VBIAS = 3.3V
VIN = 1.8V
VOUT = 1.0V
IOUT = 1.5A
COUT = 1µF ceramic
OUTPUT VOLTAGE (V)
40
200
0
50
250
200
50
DROPOUT VOLTAGE (mV)
60
DROPOUT VOLTAGE (V)
70
60
300
BIAS CURRENT (mA)
70
PSRR (dB)
80
Dropout Voltage
(Input Suppl )
400
Power Supply Rejection Ratio
(Bias Suppl )
80
400
PSRR (dB)
Power Supply Rejection Ratio
(Input Suppl )
35
30 I
= 750mA
OUT
25
20
15
I
OUT
= 1500mA
IOUT = 100mA
10
5
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE( °C)
4
I
= 10mA
OUT
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
M9999-111306
Micrel, Inc.
MIC49150
Typical Characteristics (cont.)
8
6
IOUT = 0mA
VIN = 2.5V
VOUT = 1.5V
4
2
0
1600
1400
1200
1000
800
600
400
0
0
200
10
3
3.5
OUTPUT CURRENT (mA)
Bias Current
vs. Bias Voltage
30
IBIAS
20
10
3
BIAS CURRENT (mA)
300
3.5
4 4.5 5 5.5 6
BIAS VOLTAGE (V)
Bias Current
vs. Input Voltage
VBIAS = 5V
250 VOUT = 1.5V
1500mA
750mA
100
50
0
0
1.55
0.5
1
1.5
2
INPUT VOLTAGE (V)
IOUT = 1500mA
VIN = 2.5V
VOUT = 1.5V
3.5
VBIAS = 5V
1.54
VIN = 2.5V
1.53
1.52
1.51
1.50
1.49
1.48
1.47
1.46
1.45
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
4 4.5 5 5.5 6
BIAS VOLTAGE (V)
6.5
Reference Voltage
vs. Input Voltage
0.900
3.0
2.4
3.4
4.4
5.4
INPUT VOLTAGE (V)
6.4
2.5
2.0
1.5
VBIAS = 5V
VIN = 2.5V
VOUT = 0V
0.5
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
5
10
8
6
IOUT = 100mA
VIN = 2.5V
VOUT = 1.5V
4
2
3
3.5
4 4.5 5 5.5 6
BIAS VOLTAGE (V)
6.5
20
18 VBIAS = 5V
16 VOUT = 1.5V
IOUT = 100mA
14
12
10
8
IOUT = 0mA
6
4
2
0
0
0.5
1
1.5
2
2.5
INPUT VOLTAGE (V)
Reference Voltage
vs. Bias Voltage
VIN = 2.5V
0.900
0.899
3
Short Circuit Current
vs. Temperature
1.0
IBIAS
0.901
VBIAS = 5V
0.899
1.4
2.5
Output Voltage
vs. Temperature
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20
3
Bias Current
vs. Bias Voltage
Bias Current
vs. Input Voltage
30
10
12
0
6.5
IBIAS
0.901
200
150
40
0
6.5
REFERENCE VOLTAGE (V)
0
OUTPUT VOLTAGE (V)
GROUND CURRENT (mA)
40
4 4.5 5 5.5 6
BIAS VOLTAGE (V)
Bias Current
vs. Bias Voltage
50
IOUT = 750mA
VIN = 2.5V
VOUT = 1.5V
SHORT CIRCUIT CURRENT (A)
GROUND CURRENT (mA)
50
GROUND CURRENT (mA)
20
10
BIAS CURRENT (mA)
IBIAS
REFERENCE VOLTAGE (V)
30
14
12
1.6
ENABLE THRESHOLD (V)
CURRENT (mA)
40
Ground Current
vs. Bias Voltage
14
VBIAS = 5V
VIN = 2.5V
VOUT = 1.5V
GROUND CURRENT (mA)
50
Bias Current
vs. Output Current
3.5
4 4.5 5 5.5 6
BIAS VOLTAGE (V)
6.5
Enable Threshold
vs. Bias Voltage
1.4
ON
1.2
1.0
OFF
0.8
0.6
0.4
VIN = 2.5V
0.2
0
3
3.5
4 4.5 5 5.5 6
BIAS VOLTAGE (V)
6.5
M9999-111306
Micrel, Inc.
MIC49150
Typical Characteristics (cont.)
ENABLE THRESHOLD (V)
1.6
1.4
Enable Threshold
vs. Temperature
ON
1.2
1.0
0.8
OFF
0.6
0.4
0.2
VBIAS = 5V
VIN = 2.5V
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
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MIC49150
Functional Characteristics
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MIC49150
Functional Diagram
VBIAS
VIN
Ilimit
VEN/ADJ
Fixed
Enable
Bandgap
Adj.
VIN Open
Circuit
Fixed
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R1
VOUT
R2
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MIC49150
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
tantalum capacitor to ensure the same capacitance
value over the operating temperature range. Tantalum
capacitors have a very stable dielectric (10% over their
operating temperature range) and can also be used with
this device.
Application Information
The MIC49150 is an ultra-high performance, low-dropout
linear regulator designed for high current applications
requiring 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.
The MIC49150 regulator is fully protected from damage
due to fault conditions, offering linear current limiting and
thermal shutdown.
Input Capacitor
An input capacitor of 1µF or greater is recommended
when the device is more than 4" away from the bulk
supply capacitance, 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 rejection by bypassing
the input to the regulator, further improving the integrity
of the output voltage.
Bias Supply Voltage
VBIAS, requiring relatively light current, provides power to
the control portion of the MIC49150. VBIAS requires
approximately 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 during line and
load transients. Small ceramic capacitors from VBIAS to
ground help reduce high frequency noise from being
injected into the control circuitry from the bias rail and
are good design practice. Good bypass techniques
typically include one larger capacitor such as 1µF
ceramic and smaller valued capacitors such as 0.01µF
or 0.001µF in parallel with that larger capacitor to
decouple the bias supply. The VBIAS input voltage must
be 1.6V above the output voltage with a minimum VBIAS
input voltage of 3 volts.
Thermal Design
Linear regulators are simple to use. The most
complicated design parameters to consider are thermal
characteristics. Thermal design requires the following
application-specific parameters:
• Maximum ambient temperature (TA)
• Output current (IOUT)
• Output voltage (VOUT)
• Input voltage (VIN)
• Ground current (IGND)
First, calculate the power dissipation of the regulator
from these numbers and the device parameters from this
datasheet.
PD = VIN × IIN + VBIAS × IBIAS – VOUT × IOUT
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:
Input Supply Voltage
VIN provides the high current to the collector of the pass
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. A
1µF ceramic chip capacitor should satisfy most applications. Output capacitance can be increased without
bound. See “Typical Characteristic” for examples of load
transient response.
X7R dielectric ceramic capacitors are recommended
because of their temperature performance. X7R-type
capacitors change capacitance by 15% over their
operating temperature range and are the most stable
November 2006
⎛ TJ(MAX) − TA
θ SA = ⎜⎜
PD
⎝
⎞
⎟ − (θ JC + θ CS )
⎟
⎠
The heat sink may be significantly reduced in
applications where the maximum input voltage is known
and large compared 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 compromising
performance. When this technique is employed, a
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MIC49150
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.
MSOP-8
Minimum Load Current
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
power MSOP-8 package featuring half the thermal
resistance of a standard MSOP-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
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, θJC
(junction-to-case thermal resistance) and θCA (case-toambient thermal resistance). See Figure 1. 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 (case-to-sink thermal resistance) and θSA
(sink-to-ambient thermal resistance).
Using the power MSOP-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
MSOP-8 has a θJA of 80°C/W, this is significantly lower
than the standard MSOP-8 which is typically 160°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.
q JA
qJC
ground plane
heat sink area
qCA
AMBIENT
printed circuit board
Figure 1. Thermal Resistance
Figure 2 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.
900
COPPER AREA (mm2)
800
700
600
500
400
300
200
100
0
0
0.25 0.50 0.75 1.00 1.25 1.50
POWER DISSIPATION (W)
Figure 2. Copper Area vs. Power-MSOP
Power Dissipation (∆TJA)
COPPER AREA (mm2)
900
800
700
TJ = 125°C
85°C
50°C 25°C
600
500
400
300
200
100
0
0
0.25 0.50 0.75 1.00 1.25 1.50
POWER DISSIPATION (W)
Figure 3. Copper Area vs. Power-MSOP
Power Dissipation (TA)
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MIC49150
∆T = TJ(max) – TA(max)
T J(max) = 125°C
TA(max) = maximum ambient operating temperature
For example, the maximum ambient temperature is
50°C, the ∆T is determined as follows:
∆T = 125°C – 50°C
∆T = 75°C
Using Figure 2, 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 × IIN + VBIAS × IBIAS – VOUT × IOUT
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:
PD = (1.8V) × (730mA) + 3.3V(30mA) – 1.2V(750mA)
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.
PD = 513mW
From Figure 2, the minimum current of copper required
to operate this application at a ∆T of 75°C is less than
100mm2.
The θJA of this package is ideally 80°C/W, but it will vary
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 are used. The resistor value between VOUT and
the adjust pin should not exceed 10kΩ. Larger values
can cause instability. The resistor values are calculated
by:
⎞
⎛V
R1 = R2 × ⎜⎜ OUT − 1⎟⎟
⎠
⎝ 0.9
Where VOUT is the desired output voltage.
Enable
The fixed output voltage versions of the MIC49150
feature an active high enable input (EN) that allows onoff 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 VIN and pulled up
to the maximum supply voltage.
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 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 of copper
is less than 100mm2.
November 2006
11
M9999-111306
Micrel, Inc.
MIC49150
Package Information
8-Pin MSOP (MM)
5-Pin S-Pak (R)
November 2006
12
M9999-111306
Micrel, Inc.
MIC49150
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
The 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.
© 2003 Micrel, Incorporated.
November 2006
13
M9999-111306
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