MIC47050-1.8YML-TR [MICROCHIP]

FIXED POSITIVE LDO REGULATOR;
MIC47050-1.8YML-TR
型号: MIC47050-1.8YML-TR
厂家: MICROCHIP    MICROCHIP
描述:

FIXED POSITIVE LDO REGULATOR

光电二极管 输出元件 调节器
文件: 总16页 (文件大小:494K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
MIC47050  
500mA ULDO™ with Low Input  
and Low Output Voltage  
General Description  
Features  
The MIC47050 is a high-speed, ultra-low dropout, dual-  
supply NMOS ULDO™ designed to take advantage of  
point-of-load applications that use multiple supply rails to  
generate a low-voltage, high-current power supply. The  
MIC47050 can source 500mA of output current while only  
requiring a 1µF ceramic output capacitor for stability. A  
1.5% output voltage accuracy, low dropout voltage (44mV  
@ 500mA), and low ground current makes this device  
ideally suited for mobile and point-of-load applications.  
Voltage range  
– Input Voltage: 1.0V to 3.6V  
– Bias Voltage: 2.3V to 5.5V  
0.4V to 2.0V output voltage range  
Low dropout voltage of 44mV at 500mA  
±1.5% initial output voltage accuracy  
High bandwidth – very fast transient response  
Stable with a 1µF ceramic output capacitor  
Logic level enable input  
The MIC47050 has an NMOS output stage offering very  
low output impedance. The NMOS output stage makes for  
a unique ability to respond very quickly to sudden load  
changes such as that required by a microprocessor, DSP  
or FPGA. The MIC47050 consumes little quiescent current  
and therefore can be used for driving the core voltages of  
UVLO on both supply voltages  
Available in thermally-enhanced 2mm x 2mm MLF® and  
Thin MLF® packages  
Junction temperature range of –40C to +125C  
mobile processors, post regulating  
converter in any processor.  
a
core DC/DC  
Applications  
The MIC47050 is available in fixed and adjustable output  
voltages in the tiny 2mm x 2mm MLF® and Thin MLF®  
packages with an operating junction temperature range of  
40C to 125C.  
Data sheets and support documentation can be found on  
Micrel’s web site at: www.micrel.com.  
Point-of-load applications  
PDAs, notebooks, and desktops  
Datacom and telecom systems  
DSP, PLD and FPGA power supply  
Low-voltage post regulation  
_________________________________________________________________________________________________________________________  
Typical Application  
ULDO is a trademark of Micrel Inc.  
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.  
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com  
M9999-040312-B  
April 2012  
Micrel, Inc.  
MIC47050  
Ordering Information  
Marking  
Code(2)  
Temperature  
Range  
Lead  
Part Number  
Voltage (1)  
Package  
Finish(3)  
MIC47050-1.2YML(4)  
MIC47050-1.8YML(4)  
MIC47050YML(4)  
1.2  
1.8  
6-Pin 2mm x 2mm MLF®  
6-Pin 2mm x 2mm MLF®  
Pb-Free  
40C to 125C  
40C to 125C  
40C to 125C  
40C to 125C  
40C to 125C  
ZG4  
Pb-Free  
Pb-Free  
Pb-Free  
Pb-Free  
ZGG  
ADJ  
1.2  
6-Pin 2mm x 2mm MLF®  
ZGA  
ZG4  
MIC47050-1.2YMT(5)(6)  
MIC47050-1.8YMT(5)(6)  
6-Pin 2mm x 2mm Thin MLF®  
6-Pin 2mm x 2mm Thin MLF®  
1.8  
ZGG  
ZGA  
MIC47050YMT(5)  
ADJ  
6-Pin 2mm x 2mm Thin MLF®  
Pb-Free  
40C to 125C  
Notes:  
1. Other voltage available. Contact Micrel Marketing for details.  
2. Overbar ( ¯ ) may not be to scale.  
3. MLF® is a GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.  
4. MLF® (ML) package (Pin 1 identified = ).  
5. Thin MLF® (MT) package (Pin 1 identified = ).  
6. Contact factory for availability.  
Pin Configuration  
6-pin 2mm x 2mm MLF® - Fixed (ML)  
6-pin 2mm x 2mm MLF® - Adjustable (ML)  
6-pin 2mm x 2mm Thin MLF® - Fixed (MT)  
6-pin 2mm x 2mm Thin MLF® - Adjustable (MT)  
M9999-040312-B  
April 2012  
2
Micrel, Inc.  
MIC47050  
Pin Description  
Fixed  
ADJ  
Pin Name  
BIAS  
Pin Function  
Bias Supply. The bias supply is the power supply for the internal circuitry of the  
regulator.  
1
2
1
2
GND  
Ground. Ground pins and exposed pad must be connected externally.  
Input Supply. Drain of NMOS pass transistor which is the power input voltage for  
regulator. The NMOS pass transistor steps down this input voltage to create the  
output voltage.  
3
4
3
4
IN  
OUT  
Output. Output Voltage of Regulator.  
Power Good Output. Open-drain output. Output is driven low when the output voltage  
is less than the power good threshold of its programmed nominal output voltage.  
When the output goes above the power good threshold, the open-drain output goes  
high-impedance, allowing it to be pulled up to a fixed voltage.  
5
PGOOD  
6
5
6
ADJ  
EN  
Adjust Input. Connect external resistor divider to program the output voltage.  
Enable: TTL/CMOS compatible input. Logic high = enable, logic low = shutdown. Do  
not leave floating.  
EP  
EP  
GND  
Exposed thermal pad. Connect to the ground plane to maximize thermal performance.  
M9999-040312-B  
April 2012  
3
Micrel, Inc.  
MIC47050  
Absolute Maximum Ratings(1)  
Operating Ratings(2)  
IN Supply Voltage (VIN) ................................... –0.3V to +4V  
Bias Supply Voltage (VBIAS)............................. –0.3V to +6V  
Enable Voltage (VEN)....................................... –0.3V to +6V  
Power Good Voltage (VPGOOD) ....................... .–0.3V to +6V  
ADJ Pin Voltage (VADJ)................................... .–0.3V to +6V  
OUT Pin Voltage (VOUT) ....................................–0.3V to VIN  
Lead Temperature (soldering,10 sec.)....................... 260C  
Storage Temperature (TS).........................65C to +150C  
ESD Rating(3).........................................................2kV HBM  
IN Supply Voltage (VIN) ............+1.0V to +3.6V (VIN < VBIAS)  
Bias Voltage (VBIAS)...................................... +2.3V to +5.5V  
Enable Voltage (VEN)........................................... 0V to VBIAS  
Power Good Voltage (VPGOOD) ............................0V to VBIAS  
Output Voltage Range …………….. ................ 0.4V to 2.0V  
Junction Temperature (TJ) ........................40°C to +125°C  
Ambient Temperature (TA) ..........................40°C to +85°C  
Junction Thermal Resistance  
2mm x 2mm MLF®-6L (JA)................................90°C/W  
2mm x 2mm MLF®-6L (JC)................................45°C/W  
2mm x 2mm Thin MLF®-6L (JA)........................90°C/W  
2mm x 2mm Thin MLF®-6L (JC) .......................45°C/W  
Electrical Characteristics(4)  
VIN = VOUT + 0.5V; VBIAS = VOUT+2.1V; COUT = 1µF; IOUT = 100µA; TJ = 25°C, bold values indicate –40°CTJ +125°C, unless noted.  
Parameter  
Condition  
Min.  
Typ.  
Max.  
Units  
Input Supply  
Input Voltage Range (VIN)  
VIN UVLO Threshold(5)  
VIN UVLO Hysteresis  
Ground Current in Shutdown (IGND  
1.0  
0.7  
3.6  
1.0  
V
VIN Rising  
0.85  
40  
V
mV  
A  
A  
)
VEN 0.2V (Regulator Shutdown)  
0.1  
6
1.0  
15  
Ground Current (IGND  
)
IOUT = 500mA; VIN = VOUT + 0.5V  
Bias Supply  
BIAS Input Voltage (VBIAS  
VBIAS UVLO Threshold(5)  
VBIAS UVLO Hysteresis  
)
2.3  
1.7  
5.5  
2.3  
V
V
VBIAS Rising  
2.1  
75  
mV  
V
I
OUT = 100mA  
1.15  
1.25  
330  
0.1  
Dropout voltage (VBIAS - VOUT  
VBIAS Supply Current (IBIAS  
)
IOUT = 500mA  
2.1  
500  
1.0  
V
)
IOUT = 1mA; VBIAS = VOUT + 2.1V  
VEN 0.2V (Regulator Shutdown)  
A  
A  
VBIAS Supply Current in Shutdown (IBIAS  
Output Voltage  
)
Dropout voltage  
I
OUT = 100mA  
9
50  
mV  
mV  
(VIN - VOUT  
)
IOUT = 500mA  
44  
120  
I
OUT = 100A  
-1.5  
-2.0  
-0.1  
+1.5  
+2.0  
0.1  
%
%
Output Voltage Accuracy  
VBIAS Line Regulation  
IOUT = 100A  
VBIAS = VOUT + 2.1V to 5.5V  
0.015  
%/V  
M9999-040312-B  
April 2012  
4
Micrel, Inc.  
MIC47050  
Electrical Characteristics(4)  
VIN = VOUT + 0.5V; VBIAS = VOUT+2.1V; COUT = 1µF; IOUT = 100µA; TJ = 25°C, bold values indicate –40°CTJ +125°C, unless noted.  
Parameter  
Condition  
Min.  
Typ.  
0.005  
0.2  
Max.  
0.05  
0.5  
Units  
%/V  
%
VIN Line Regulation  
Load Regulation  
Current Limit  
VIN = VOUT + 0.5V to 3.6V  
IOUT = 10mA to 500mA  
-0.05  
Short Circuit Current Limit  
Enable Input  
VIN = 2.7V; VOUT = 0V  
0.6  
1.6  
2.5  
A
EN Logic Level High  
EN Logic Level Low  
EN Hysteresis  
1.0  
0.77  
0.67  
100  
1
V
V
0.2  
mV  
A  
A  
s  
VEN 0.2V (Regulator Shutdown)  
2
Enable Bias Current  
VEN = 1.0V (Regulator Enabled)  
6
10  
15  
500  
Turn-on Time  
COUT = 1F; 90% of typical VOUT  
Thermal Protection  
Over-Temperature Shutdown  
Over-Temperature Shutdown Hysteresis  
Power Good  
TJ Rising  
160  
20  
C  
C  
V
OUT Rising  
91  
89  
95  
%
%
%
V
Power Good Threshold Voltage  
VOUT Falling  
85  
-1  
Power Good Hysteresis  
2
Power Good Output Low Voltage  
Power Good Leakage Current  
0.02  
0.01  
0.1  
+1  
I
PG = 250A  
VPG = 5.0V  
A  
Reference Voltage (Adjustable Option Only)  
IOUT = 100A  
IOUT = 100A  
VFB = 0.8V  
0.394  
0.406  
V
V
Feedback Reference Voltage  
0.4  
20  
0.392  
0.408  
FB Bias Current  
nA  
Output Voltage Noise and Ripple Rejection  
Output Voltage Noise  
63  
f = 10Hz to 100kHz; IOUT = 100mA; COUT=1F  
f = 10kHz; COUT = 1.0F, IOUT = 100mA  
f = 100kHz; COUT = 1.0F, IOUT = 100mA  
VRMS  
dB  
50  
37  
Ripple Rejection  
dB  
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, 1.5kin series with 100pF.  
4. Specification for packaged product only.  
5. Both VIN and VBIAS UVLO thresholds must be met for the output voltage to turn-on. If either of the two input voltages is below the UVLO thresholds,  
the output is disabled.  
M9999-040312-B  
April 2012  
5
Micrel, Inc.  
MIC47050  
Typical Characteristics  
Output Voltage vs.  
Input Dropout Voltage vs.  
Output Current  
Input Dropout Voltage vs.  
Temperature  
Input Voltage  
50  
45  
40  
35  
30  
25  
20  
15  
10  
5
2.0  
70  
60  
50  
40  
30  
20  
10  
0
1.8  
1.6  
1.4  
1.2  
1.0  
0.8  
0.6  
IOUT = 500mA  
IOUT = 100mA  
VBIAS = 3.6V  
OUT = 1.2V  
V
VBIAS = 5.0V  
OUT = 1.8V  
OUT = 500mA  
0.4  
0.2  
0.0  
VBIAS = 5.0V  
VOUT = 1.2V  
V
I
0
0
1
2
3
4
0
100  
200  
300  
400  
500  
-40 -20  
0
20  
40  
60  
80 100 120  
INPUT VOLTAGE (V)  
OUTPUT CURRENT (mA)  
TEMPERATURE (°C)  
Output Voltage vs.  
Bias Voltage  
Bias Dropout Voltage vs.  
Output Current  
Bias Dropout Voltage vs.  
Temperature  
2.0  
1.8  
1.6  
1.4  
1.2  
1.0  
0.8  
0.6  
0.4  
0.2  
0.0  
2.2  
2.0  
1.8  
1.6  
1.4  
1.2  
1.0  
0.8  
0.6  
0.4  
0.2  
1.9  
1.8  
1.7  
1.6  
1.5  
1.4  
1.3  
1.2  
1.1  
1.0  
0.9  
IOUT = 100mA  
VOUT = 2.0V  
VOUT = 2.0V  
IOUT = 500mA  
VOUT = 1.2V  
VOUT = 1.2V  
VIN = 2.5V  
VIN = 2.5V  
VIN = 2.5V  
IOUT = 500mA  
VOUT = 1.8V  
2
3
4
5
0
100  
200  
300  
400  
500  
-40 -20  
0
20 40 60 80 100 120  
BIAS VOLTAGE (V)  
OUTPUT CURRENT (mA)  
TEMPERATURE (°C)  
Bias Current vs.  
Bias Voltage  
Bias Current vs.  
Output Current  
Bias Current vs.  
Temperature  
340  
338  
336  
334  
332  
330  
328  
326  
324  
322  
320  
440  
420  
400  
380  
360  
340  
320  
300  
280  
260  
240  
400  
380  
360  
340  
320  
300  
280  
260  
240  
VBIAS = 3.6V  
IN = 1.8V  
VOUT = 1.2V  
VBIAS = 3.6V  
IN = 1.8V  
VIN = 1.8V  
V
V
IOUT = 1mA  
VOUT = 1.2V  
3
3.5  
4
4.5  
5
5.5  
0
100  
200  
300  
400  
500  
-40 -20  
0
20 40 60 80 100 120  
BIAS VOLT AGE (V)  
OUTPUT CURRENT (mA)  
TEMPERATURE (°C)  
M9999-040312-B  
April 2012  
6
Micrel, Inc.  
MIC47050  
Typical Characteristics (Continued)  
Ground Current vs.  
Ground Current vs.  
Temperature  
Output Voltage vs.  
Output Current  
Input Voltage  
30  
1.208  
1.206  
1.204  
1.202  
1.200  
1.198  
1.196  
1.194  
1.192  
1.190  
7.00  
VBIAS = 5.0V  
6.75  
VOUT = 1.2V  
25  
20  
15  
10  
5
6.50  
6.25  
6.00  
5.75  
5.50  
5.25  
5.00  
4.75  
4.50  
4.25  
4.00  
IOUT = 500mA  
VBIAS = 3.6V  
IN = 1.8V  
OUT = 1.2V  
V
VBIAS = 3.6V  
IN = 1.8V  
V
V
IOUT = 500mA  
0
0
100  
200  
300  
400  
500  
-40 -20  
0
20 40 60 80 100 120  
1.2  
1.6  
2
2.4  
2.8  
3.2  
3.6  
OUTPUT CURRENT (mA)  
INPUT VOLTAGE (V)  
TEMPERATURE (°C)  
Current Limit vs.  
Input Voltage  
Current Limit vs.  
Temperature  
Output Voltage vs.  
Temperature  
1.80  
1.75  
1.70  
1.65  
1.60  
1.55  
1.50  
1.45  
1.40  
1.220  
1.215  
1.210  
1.205  
1.200  
1.195  
1.190  
1.185  
1.180  
1.90  
1.85  
1.80  
1.75  
1.70  
1.65  
1.60  
1.55  
1.50  
1.45  
1.40  
1.35  
1.30  
VBIAS = 3.6V  
IN = 1.8V  
VBIAS = 3.6V  
IN = 1.8V  
V
VBIAS = 5.0V  
VOUT = 1.2V  
V
IOUT = 100µA  
VOUT = 1.2V  
1.5  
2
2.5  
3
3.5  
4
-40 -20  
0
20 40 60 80 100 120  
-40 -20  
0
20 40 60 80 100 120  
INPUT VOLTAGE (V)  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
Power Supply Ripple Rejection  
(Input Voltage)  
Power Supply Ripple Rejection  
(Bias Voltage)  
Output Noise  
90  
90  
10  
1
80  
70  
60  
50  
40  
30  
20  
10  
0
80  
70  
60  
50  
40  
30  
20  
10  
0
0.1  
VBIAS = 3.6V  
IN = 1.8V  
VBIAS = 3.6V  
VBIAS = 3.6V ± 300mV  
V
0.01  
V
IN = 1.8V ± 300mV  
VOUT = 1.2V  
OUT = 500mA  
V
IN = 1.8V  
VOUT = 1.2V  
VOUT = 1.2V  
Noise (10Hz-100kHz) = 56.19µVRMS  
I
IOUT = 500mA  
0.001  
0.01  
0.1  
1
10  
100  
1000  
0.01  
0.1  
1
10  
100  
1000  
0.01  
0.1  
1
10  
100  
1000  
Frequency (kHz)  
FREQUENCY (kHz)  
Frequency (kHz)  
M9999-040312-B  
April 2012  
7
Micrel, Inc.  
MIC47050  
Functional Characteristics  
M9999-040312-B  
April 2012  
8
Micrel, Inc.  
MIC47050  
Functional Diagram  
MIC47050 Fixed Output Block Diagram  
MIC47050 Adjustable Output Block Diagram  
M9999-040312-B  
April 2012  
9
Micrel, Inc.  
MIC47050  
Functional Description  
The MIC47050 is a high-speed, ultra-low dropout, dual  
supply NMOS ULDO™ designed to take advantage of  
point-of-load applications that use multiple supply rails to  
generate a low-voltage, high-current power supply. The  
MIC47050 can source 0.5A of output current while only  
requiring a 1µF ceramic output capacitor for stability.  
The MIC47050 regulator is fully protected from damage  
due to fault conditions, offering linear current limiting and  
thermal shutdown.  
Tantalum capacitors have a very stable dielectric (10%  
over their operating temperature range) and can also be  
used with this device. See the Typical Characteristic  
section for examples of load transient response.  
Output Capacitor  
The MIC47050 requires an output capacitor of 1µF or  
greater to maintain stability. The design is optimized for  
use with low-ESR ceramic chip capacitors. High-ESR  
capacitors may cause high-frequency oscillation. The  
output capacitor can be increased, but performance has  
been optimized for a 1µF ceramic output capacitor and  
does not improve significantly with larger capacitance.  
Bias Supply Voltage  
VBIAS, requiring relatively light current, provides power to  
the control portion of the MIC47050. Bypassing on the  
bias pin is recommended to improve performance of the  
regulator during line and load transients. Small 0.1µF  
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.  
The output capacitor type and placement criteria are the  
same as the input capacitor. See the “Input Capacitor”  
subsection for a detailed description.  
Minimum Load Current  
The MIC47050, unlike most other regulators, does not  
require a minimum load to maintain output voltage  
regulation.  
Input Supply Voltage  
VIN provides the supply to power the LDO. The minimum  
input voltage is 1.0V. This allows conversion from low  
voltage supplies to reduce the power dissipation in the  
pass element.  
Adjustable Regulator Design  
The MIC47050 adjustable version allows programming  
the output voltage from 0.4V to 2.0V. Two external  
resistors are required. The R1 resistor value between  
Input Capacitor  
The MIC47050 is a high-performance, high bandwidth  
device. Therefore, it requires a well-bypassed input  
supply for optimal performance. A 1µF capacitor is the  
minimum required for stability. A 10µF ceramic capacitor  
is recommended for most applications, especially if the  
LDO’s headroom (VIN –VOUT) is small and/or large load  
transients are present. Fast load transient and low  
headroom requires a larger input filter capacitor to  
ensure that the regulator does not drop out of regulation.  
A 10µF will better attenuate any voltage glitches from  
exceeding the maximum voltage rating of the part.  
V
OUT and the ADJ pin should not exceed 10k, as larger  
values can cause instability. R2 connects between the  
ADJ pin and ground. The resistor values are calculated  
as follows:  
VOUT  
R1 R2 V  
1  
REF  
Where VOUT is the desired output voltage and VREF is the  
internal reference voltage.  
Additional high-frequency capacitors, such as small-  
valued NPO dielectric-type capacitors, help filter out  
high-frequency noise and are good practice in any RF-  
based circuit.  
Enable/Shutdown  
The MIC47050 comes with a single active-high enable  
pin that allows the regulator to be disabled. Forcing the  
enable pin low disables the regulator and sends it into a  
“zero” off-mode-current state. In this state, current  
consumed by the regulator goes nearly to zero. Forcing  
the enable pin high enables the output voltage. The  
active-high enable pin uses CMOS technology and the  
enable pin cannot be left floating; a floating enable pin  
may cause an indeterminate state on the output.  
X7R and X5R 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 type of ceramic capacitors. Z5U and  
Y5V dielectric capacitors are not recommended since  
they 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.  
M9999-040312-B  
April 2012  
10  
Micrel, Inc.  
MIC47050  
TJ(MAX) = 125°C, the maximum junction temperature of  
the die.  
Power Good (PGOOD)  
The Power Good (PGOOD) pin is an open drain output  
that goes low when the output voltage (fixed version)  
drops below the PGOOD threshold voltage.  
θJA thermal resistance = 90°C/W.  
Table 1 shows junction-to-ambient thermal resistance for  
the MIC47050 in the MLF® or Thin MLF® package.  
The pull-up resistor value should be large enough to  
guarantee a proper “low” voltage when the PGOOD pin  
pulls low. The PGOOD low voltage is typically 0.1V at  
250µA current.  
recommended when pulling up to 3.3V bias.  
A
10kresistor or greater is  
θJA Recommended  
Min. Footprint  
Package  
θJC  
6-pin 2mm x 2mm MLF®  
90°C/W  
45°C/W  
45°C/W  
If the PGOOD function is not required, the PGOOD pin  
may be left unconnected.  
6-pin 2mm x 2mm  
Thin MLF®  
90°C/W  
Thermal Shutdown  
Table 1. Thermal Resistance  
The MIC47050 has an internal over-temperature  
protection feature. This feature is for protection only.  
The device should never be intentionally operated near  
this temperature as this may reduce long term reliability.  
The device will turn off when the over-temperature  
threshold is exceeded. A 20°C hysteresis is built in to  
allow the device to cool before turning back on.  
Substituting PD for PD(max) and solving for the ambient  
operating temperature will give the maximum operating  
conditions for the regulator circuit. The junction-to-  
ambient thermal resistance for the minimum footprint is  
90°C/W. The maximum power dissipation must not be  
exceeded for proper operation. For example, when  
operating the MIC47050-1.2YML at an input voltage of  
1.8V and a 0.5A load with a minimum footprint layout,  
the maximum ambient operating temperature TA can be  
determined as follows:  
Thermal Considerations  
The MIC47050 is designed to provide 0.5A of continuous  
current in a very small package. Maximum ambient  
operating temperature can be calculated based on the  
output current and the voltage drop across the part.  
Given that the input voltage is 1.8V, the output voltage is  
1.2V and the output current is 0.5A. The actual power  
dissipation of the regulator circuit can be determined  
using the equation:  
T
T  
J(MAX)  
Θ  
P  
JA D(MAX)  
A
T
125C 90C/W 0.3W  
98C  
A
A
T
P
V
VOUT
I  
V I  
OUT  
IN GND  
V  
I  
D
IN  
BIAS BIAS  
Therefore, a 1.2V application with 0.5A of output current  
can accept an ambient operating temperature of 98°C in  
a 2mm x 2mm MLF® or Thin MLF® package.  
Because this device is CMOS, the ground current is  
insignificant for power dissipation and can be ignored for  
this calculation.  
Thermal Measurements  
Measuring the IC’s case temperature is recommended to  
insure it is within its operating limits. Although this might  
seem like a very elementary task, it is easy to get  
erroneous results. The most common mistake is to use  
the standard thermal couple that comes with a thermal  
meter. This thermal couple wire gauge is large, typically  
22 gauge, and behaves like a heatsink, resulting in a  
lower case measurement.  
P
1.8V 1.2V 0.5A 0.3W  
D
To determine the maximum ambient operating  
temperature of the package, use the junction-to-ambient  
thermal resistance of the device and the following basic  
equation:  
Two methods of temperature measurement are using a  
smaller thermal couple wire or an infrared thermometer.  
If a thermal couple wire is used, it must be constructed  
of 36 gauge wire or higher (smaller wire size) to  
minimize the wire heat-sinking effect.  
T
T  
A   
J(MAX)  
P
D(MAX)  
Θ
JA  
M9999-040312-B  
April 2012  
11  
Micrel, Inc.  
MIC47050  
In addition, the thermal couple tip must be covered in  
either thermal grease or thermal glue to make sure that  
the thermal couple junction is making good contact with  
the case of the IC. Omega brand thermal couple (5SC-  
TT-K-36-36) is adequate for most applications.  
Wherever possible, an infrared thermometer is  
recommended. The measurement spot size of most  
infrared thermometers is too large for an accurate  
reading on a small form factor ICs. However, a IR  
thermometer from Optris has a 1mm spot size, which  
makes it a good choice for the 2mm x 2mm MLF® or  
Thin MLF® package. An optional stand makes it easy to  
hold the beam on the IC for long periods of time.  
For a full discussion of heat sinking and thermal effects  
of voltage regulators, refer to the “Regulator Thermals”  
section of Micrel’s Designing with Low-Dropout Voltage  
Regulators handbook. This information can be found on  
Micrel's website at:  
http://www.micrel.com/_PDF/other/LDOBk_ds.pdf  
M9999-040312-B  
April 2012  
12  
Micrel, Inc.  
MIC47050  
MIC47050 Typical Application Schematic  
MIC47050 Adjustable Output  
MIC47050 Fixed Output  
M9999-040312-B  
April 2012  
13  
Micrel, Inc.  
MIC47050  
MIC47050 Bill of Materials  
Item Part Number  
Manufacturer  
Murata(1)  
Description  
Qty.  
GRM21BR60J106ME19  
Ceramic Capacitor, 10µF, 6.3V, X5R, 0603 size  
Ceramic Capacitor, 10µF, 6.3V, X5R, 0603 size  
Capacitor, 1µF, 10V, X5R, 0402 size  
C1  
1
C1608X5R0J106MT  
TDK(2)  
Murata(1)  
TDK(2)  
GRM155R61A105KE15D  
C2  
1
C1005X5R0J105KT  
Capacitor, 1µF, 10V, X5R, 0402 size  
C3  
R1  
R2  
R3  
06035D104MAT2A  
CRCW06031001FRT1  
CRCW06036650FRT1  
CRCW06031002FRT1  
MIC47050YML  
AVX(3)  
Ceramic Capacitor, 0.1µF, 50V, X5R, 0603 size  
Resistor, 1k (0603 size), 1%  
1
1
1
1
Vishay Dale(4)  
Vishay Dale(4)  
Vishay Dale(4)  
Resistor, 665 (0603 size), 1%  
Resistor, 10k (0603 size), 1%  
Low Input and Output 500mA ULDO™ - Adjustable Output  
Low Input and Output 500mA ULDO™ - Adjustable Output  
Low Input and Output 500mA ULDO™ - Fixed 1.2V Output  
Low Input and Output 500mA ULDO™ - Fixed 1.2V Output  
Low Input and Output 500mA ULDO™ - Fixed 1.8V Output  
Low Input and Output 500mA ULDO™ - Fixed 1.8V Output  
MIC47050YMT  
MIC47050-1.2YML  
MIC47050-1.2YMT  
MIC47050-1.8YML  
MIC47050-1.8YMT  
U1  
Micrel, Inc.(5)  
1
Notes:  
1. Murata: www.murata.com.  
2. TDK: www.tdk.com.  
3. AVX: www.avx.com.  
4. Vishay: www.vishay.com .  
5. Micrel, Inc.: www.micrel.com.  
M9999-040312-B  
April 2012  
14  
Micrel, Inc.  
MIC47050  
Package Information  
6-Pin 2mm 2mm Thin MLF® (MT)  
M9999-040312-B  
April 2012  
15  
Micrel, Inc.  
MIC47050  
Package Information (Continued)  
6-Pin 2mm x 2mm MLF® (ML)  
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  
Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This  
information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,  
specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual  
property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability  
whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties  
relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right.  
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.  
© 2012 Micrel, Incorporated.  
M9999-040312-B  
April 2012  
16  

相关型号:

MIC47050-1.8YMT

500mA ULDO? with Low Input and Low Output Voltage
MICREL

MIC47050-1.8YMTTR

暂无描述
MICREL

MIC47050YML

500mA ULDO? with Low Input and Low Output Voltage
MICREL

MIC47050YML-TR

ADJUSTABLE POSITIVE LDO REGULATOR
MICROCHIP

MIC47050YMT

500mA ULDO? with Low Input and Low Output Voltage
MICREL

MIC47050YMT-TR

暂无描述
MICROCHIP

MIC47050_12

500mA ULDO? with Low Input and Low Output Voltage
MICREL

MIC47053

500mA Micropower ULDO™ Linear Regulator
MICREL

MIC47053YMT

500mA Micropower ULDO™ Linear Regulator
MICREL

MIC47053YMT-T5

ADJUSTABLE POSITIVE LDO REGULATOR
MICROCHIP

MIC47053YMT-TR

ADJUSTABLE POSITIVE LDO REGULATOR
MICROCHIP

MIC47100

1A High Speed Low VIN LDO
MICREL