FLF3215T-R47N [MICREL]
4MHz, 2A, 100% Duty Cycle Buck Regulator with HyperLight Load® and Power Good; 为4MHz ，2A ， 100 ％占空比降压型稳压器的HyperLight Load®和电源良好
| 型号： | FLF3215T-R47N |
| 厂家： | 
MICREL SEMICONDUCTOR |
| 描述： | 4MHz, 2A, 100% Duty Cycle Buck Regulator with HyperLight Load® and Power Good |
| 文件： | 总19页 (文件大小：1106K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MIC23163/4
4MHz, 2A, 100% Duty Cycle Buck Regulator
with HyperLight Load® and Power Good
General Description
Features
The MIC23163/4 is
a
high-efficiency, 4MHz, 2A,
• Input voltage: 2.7V to 5.5V
• 100% duty cycle
• 2A output current
• Up to 93% peak efficiency
• 85% typical efficiency at 1mA
• Programmable soft-start with pre-bias start-up capability
• Power Good (PG) Indicator
• 4MHz PWM operation in continuous mode
• Ultra-fast transient response
synchronous buck regulator with HyperLight Load® (HLL)
mode and maximum 100% duty cycle. HLL provides very-
high efficiency at light loads and ultra-fast transient
response which makes the MIC23163/4 perfectly suited for
supplying processor core voltages. An additional benefit of
this proprietary architecture is very low output ripple
voltage throughout the entire load range with the use of
small output capacitors. The tiny 2.0mm × 2.0mm DFN
package saves precious board space and requires only
three external components.
• Low ripple output voltage
• Fully-integrated MOSFET switches
• 0.1µA shutdown current
The MIC23163/4 is designed for use with a very small
0.47µH inductor and 10µF output capacitor that enables a
total solution size, less than 1mm height.
• Thermal shutdown and current-limit protection
• 10-pin 2.0mm × 2.0mm Thin DFN
• –40°C to +125°C junction temperature range
• Disable pull down 180Ω (MIC23164 only)
The MIC23163/4 has a very low quiescent current of 33µA
and achieves as high as 85% efficiency at 1mA. At higher
loads, the MIC23163/4 provides a constant switching
frequency around 4MHz while achieving peak efficiencies
up to 93%. The MIC23164 incorporates an active
discharge feature that switches an 180Ω FET to ground to
discharge the output when the part is disabled.
Applications
• Cellular modems
• Mobile handsets
• Portable media/MP3 players
• Portable navigation devices (GPS)
• WiFi/WiMax/WiBro modules
• Digital cameras
The MIC23163/4 is available in 10-pin 2.0mm × 2.0mm
DFN package with an operating junction temperature
range from –40°C to +125°C.
Datasheets and support documentation are available on
Micrel’s web site at: www.micrel.com.
• Wireless LAN cards
Typical Application
HyperLight Load is a registered trademark of Micrel, 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
Revision 2.0
June 29, 2013
Micrel, Inc.
MIC23163/4
Ordering Information
Marking
Part Number
Output
Voltage
Auto
Discharge
Junction Temperature Range
Package(1, 2)
Code
MIC23163YMT
MIC23164YMT
QAQ
KQA
ADJ
ADJ
No
10-Pin 2mm × 2mm Thin DFN
10-Pin 2mm × 2mm Thin DFN
–40°C to +125°C
–40°C to +125°C
Yes
Note:
1. DFN is a GREEN, RoHS-compliant package. Mold compound is Halogen Free.
2. DFN ▲ = Pin 1 identifier.
Pin Configuration
2mm × 2mm DFN (MT)
Adjustable Output Voltage
(Top View)
Pin Description
Pin Number
Pin Name
Pin Function
Switch (Output): Internal power MOSFET output switches. Disable pull down 180Ω
(MIC23164 only).
1
SW
EN
Enable (Input): Logic high enables operation of the regulator. Logic low will shut down the
device. Do not leave floating.
2
3
4
FB
Feedback: Connect a resistor divider from the output to ground to set the output voltage.
Not Internally Connected.
NC
Power Good: Open drain output for the power good indicator. Use a pull-up resistor from this pin
to a voltage source to detect a power good condition.
5
6
7
PG
SS
Soft Start: Place a capacitor from this pin to ground to program the soft start time. Do not leave
floating, 100pF minimum CSS is required.
Analog Ground: Connect to central ground point where all high-current paths meet (CIN, COUT
PGND) for best operation.
,
AGND
8
9
AVIN
PVIN
PGND
ePad
Analog Input Voltage: Connect a capacitor to ground to decouple the noise.
Power Input Voltage: Connect a capacitor to PGND to decouple the noise.
Power Ground.
10
EP
Exposed Pad. Connect to GND.
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MIC23163/4
Absolute Maximum Ratings(3)
Operating Ratings(4)
Supply Voltage (VAVIN, VPVIN)............................ 2.7V to 5.5V
Enable Input Voltage (VEN) .. ……………………….0V to VIN
Feedback Voltage (VFB) ...................................... 0.7V to VIN
Junction Temperature Range (TJ).. ….−40°C ≤ TJ ≤ +125°C
Thermal Resistance
Supply Voltage (VAVIN, VPVIN)............................. −0.3V to 6V
Power Good Voltage (VPG)................................ −0.3V to 6V
Output Switch Voltage (VSW)............................. −0.3V to 6V
Enable Input Voltage (VEN)................................−0.3V to VIN
Junction Temperature (TJ) .......................................+150°C
Storage Temperature Range (TS).............−65°C to +150°C
Lead Temperature (soldering, 10s)............................ 260°C
ESD Rating(5)................................................. ESD Sensitive
2mm x 2mm Thin DFN -10 (θJA).........................90°C/W
2mm x 2mm Thin DFN -10 (θJC).........................45°C/W
Electrical Characteristics(6)
TA = 25°C; VIN = VEN = 3.6V; L = 0.47µH; COUT = 10µF unless otherwise specified. Bold values indicate –40°C ≤ TJ ≤ +125°C, unless
otherwise noted.
Parameter
Condition
Min.
2.7
Typ.
Max.
5.5
Units
V
Supply Voltage Range
Undervoltage Lockout Threshold
Undervoltage Lockout Hysteresis
Quiescent Current
2.40
2.65
(Turn-On)
2.53
75
V
mV
µA
µA
55
5
33
IOUT = 0mA , VSNS > 1.2 × VOUT Nominal
VEN = 0V; VIN = 5.5V
Shutdown Current
0.1
VIN = 3.6V if VOUTNOM < 2.5V, ILOAD = 20mA
VIN = 4.5V if VOUTNOM ≥ 2.5V, ILOAD = 20mA
+2.5
0.72
Output Voltage Accuracy
−2.5
%
0.68
2.5
Feedback Regulation Voltage
Current Limit
0.7
3.3
V
A
VSNS = 0.9*VOUTNOM
VIN = 3.6V to 5.5V if VOUTNOM < 2.5V, ILOAD = 20mA
VIN = 4.5V to 5.5V if VOUTNOM ≥ 2.5V, ILOAD = 20mA
20mA < ILOAD < 500mA, VIN = 3.6V if VOUTNOM < 2.5V
20mA < ILOAD < 500mA, VIN = 5.0V if VOUTNOM ≥ 2.5V
20mA < ILOAD < 1A, VIN = 3.6V if VOUTNOM < 2.5V
20mA < ILOAD < 1A, VIN = 5.0V if VOUTNOM ≥ 2.5V
ISW = 100mA PMOS
Output Voltage Line Regulation
0.3
0.3
0.3
%/V
Output Voltage Load Regulation
%
0.13
0.13
PWM Switch ON-Resistance
Switching Frequency
Ω
ISW = −100mA NMOS
IOUT = 120mA
4
MHz
µs
Soft-Start Time
Soft-Start Current
Power Good Threshold (Rising)
Notes:
VOUT = 90%, CSS = 1nF
1000
2.2
90
VSS = 0V
µA
%
% of VNOM
85
95
3. Exceeding the absolute maximum ratings may damage the device.
4. The device is not guaranteed to function outside its operating ratings.
5. Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF.
6. Specification for packaged product only.
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MIC23163/4
Electrical Characteristics(6) (Continued)
TA = 25°C; VIN = VEN = 3.6V; L = 0.47µH; COUT = 10µF unless otherwise specified. Bold values indicate –40°C ≤ TJ ≤ +125°C, unless
otherwise noted.
Parameter
Condition
Min.
Typ.
Max.
Units
%
Power Good Threshold Hysteresis
Power Good Pull-Down
Enable Threshold
7
VSNS = 90% VNOMINAL, IPG = 1mA
Turn-On
200
1.2
2
mV
V
0.5
0.8
0.1
160
Enable Input Current
Overtemperature Shutdown
µA
°C
Overtemperature Shutdown
Hysteresis
20
°C
SW Pull-Down Resistance
(MIC23164 only)
V
EN = 0V
180
Ω
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MIC23163/4
Typical Characteristics
Efficiency vs. Output Current
VOUT = 1.8V @ 25°C
VOUT Rise Time vs. CSS
Efficiency vs. Output Current
VOUT = 3.3V @ 25°C
95
100
95
90
85
80
75
70
65
60
55
50
1000000
100000
10000
1000
100
VIN = 3V
VIN = 4.2V
90
85
VIN = 5V
VIN = 3.6V
80
VIN = 5V
75
70
65
60
55
50
10
VIN = 3.6V
1
1
10
100
1000
10000
1
10
100
1000
10000
1000
10000
100000
1000000
OUTPUT CURRENT (mA)
CSS (pF)
OUTPUT CURRENT (mA)
Current Limit vs.
Input Voltage
IQ vs. Temperature
Quiscent Current vs.
Input Voltage
3.8
3.6
3.4
3.2
3
50
45
40
35
30
25
20
50
48
46
44
42
40
38
36
34
32
30
2.8
2.6
TCASE = 25°C
VIN = 3.6V
TCASE = 25°C
4.5 5.0 5.5
-40 -20
0
20
40
60
80
100 120
2.5
3.0
3.5
4.0
4.5
5.0
5.5
2.5
3.0
3.5
4.0
TEMPERATURE (°C)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
Line Regulation
(Light Loads)
Line Regulation
(High Loads)
Output Voltage vs.
Output Current (DCM)
1.864
1.863
1.862
1.861
1.860
1.859
1.858
1.857
1.856
1.855
1.854
1.870
1.820
1.815
1.810
1.805
1.800
1.795
1.790
1.868
1.866
1.864
1.862
1.860
1.858
1.856
1.854
1.852
1.850
IOUT = 1A
IOUT = 30mA
IOUT = 300mA
IOUT = 130mA
VIN = 3.6V
0
20 40 60 80 100 120 140 160 180 200
2.5
3.0
3.5
4.0
4.5
5.0
5.5
2.5
3.0
3.5
4.0
4.5
5.0
5.5
OUTPUT CURRENT (mA)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
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Micrel, Inc.
MIC23163/4
Typical Characteristics (Continued)
Output Voltage vs.
Output Current (CCM)
PG Thresholds vs.
Input Voltage
Output Voltage vs.
Temperature
1.820
1.815
1.810
1.805
1.800
1.795
1.790
1.785
1.780
92
91
90
89
88
87
86
85
84
83
82
2.100
2.080
2.060
2.040
2.020
2.000
1.980
1.960
1.940
1.920
1.900
PG RISING
PG FALLING
VIN = 3.6V
IOUT = 30mA
VIN = 3.6V
-40 -20
0
20
40
60
80 100 120
200
500
800
1100 1400 1700 2000
2.5
3.0
3.5
4.0
4.5
5.0
5.5
TEMPERATURE (°C)
OUPUT CURRENT (mA)
INPUT VOLTAGE (V)
UVLO Thresholds vs.
Temperature
PG Delay Time
vs. Input Voltage
Enable Thresholds
vs. Input Voltage
40
35
30
25
20
15
10
2.58
2.56
2.54
2.52
2.5
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0.60
PG RISING
UVLO ON
PG FALLING
UVLO OFF
2.48
2.46
TCASE = 25°C
4.5 5.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
-40 -20
0
20
40
60
80 100 120
2.5
3.0
3.5
4.0
5.5
INPUT VOLTAGE (V)
TEMPERATURE (°C)
INPUT VOLTAGE (V)
Enable Threshold vs.
Temperature
Switching Frequency vs.
Output Current
Feedback Voltage vs.
Temperature
1.00
10000
1000
100
10
0.720
0.715
0.710
0.705
0.700
0.695
0.690
0.685
0.680
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0.60
VIN = 3.6V
VIN = 5V
VIN = 3.6V
1
-40 -20
0
20
40
60
80 100 120
1
10
100
1000
10000
-40 -20
0
20
40
60
80 100 120
TEMPERATURE (°C)
OUPUT CURRENT (mA)
TEMPERATURE (°C)
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MIC23163/4
Typical Characteristics (Continued)
Shutdown Current vs.
Temperature
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
-40 -20
0
20
40
60
80 100 120
TEMPERATURE (°C)
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MIC23163/4
Functional Characteristics
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MIC23163/4
Functional Characteristics (Continued)
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MIC23163/4
Functional Characteristics (Continued)
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MIC23163/4
Functional Diagram
Figure 1. Simplified MIC23163/4 Functional Block Diagram − Adjustable Output Voltage
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Micrel, Inc.
MIC23163/4
PG
Functional Description
The power good (PG) pin is an open drain output which
indicates logic high when the output voltage is typically
above 90% of its steady state voltage. A pull-up resistor
VIN
The input supply (VIN) provides power to the internal
MOSFETs for the switch-mode regulator along with the
internal control circuitry. The VIN operating range is 2.7V
to 5.5V so an input capacitor, with a minimum voltage
rating of 6.3V, is recommended. Due to the high
switching speed, a minimum 2.2µF bypass capacitor
placed close to VIN and the power ground (PGND) pin is
required. Refer to the “PCB Layout Recommendations”
section for details.
of more than 5kΩ should be connected from PG to VOUT
.
SS
The soft start (SS) pin is used to control the output
voltage ramp up time. The approximate equation for the
ramp time in seconds is 270 × 103 × ln(10) × CSS. For
example, for a CSS = 1nF, TRISE ~ 600µs. The minimum
recommended value for CSS is 1nF.
FB
EN/Shutdown
The feedback (FB) pin is provided for the adjustable
voltage option (no internal connection for fixed options).
This is the control input for programming the output
voltage. A resistor divider network is connected to this pin
from the output and is compared to the internal 0.7V
reference within the regulation loop.
A logic high signal on the enable pin activates the output
voltage of the device. A logic low signal on the enable pin
deactivates the output and reduces supply current to
0.1µA. When disabled the MIC23164 switches an internal
load of 180Ω on the regulators switch node to discharge
the output. The MIC23163/4 features external soft-start
circuitry via the soft start (SS) pin that reduces in-rush
current and prevents the output voltage from
overshooting at start up. Do not leave the EN pin floating.
The output voltage can be programmed between 0.7V
and VIN using Equation 1:
R1
R2
SW
VOUT = VREF × 1+
Eq. 1
The switch (SW) connects directly to one end of the
inductor and provides the current path during switching
cycles. The other end of the inductor is connected to the
load, SNS pin and output capacitor. Due to the high-
speed switching on this pin, the switch node should be
routed away from sensitive nodes whenever possible.
where:
R1 is the top resistor, R2 is the bottom resistor.
Table 1. Example Feedback Resistor Values
AGND
The analog ground (AGND) is the ground path for the
biasing and control circuitry. The current loop for the
signal ground should be separate from the power ground
VOUT
1.2V
1.5V
1.8V
2.5V
3.3V
3.6V
R1
R2
215k
301k
340k
274k
383k
422k
301k
261k
215k
107k
102k
102k
(PGND)
loop.
Refer
to
the
“PCB
Layout
Recommendations” section for details.
PGND
The power ground pin is the ground path for the high
current in PWM mode. The current loop for the power
ground should be as small as possible and separate from
the analog ground (AGND) loop as applicable. Refer to
the “PCB Layout Recommendations” section for details.
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MIC23163/4
Maximum current ratings of the inductor are generally
given in two methods; permissible DC current and
saturation current. Permissible DC current can be rated
either for a 40°C temperature rise or a 10% to 20% loss
in inductance. Ensure the inductor selected can handle
the maximum operating current. When saturation current
is specified, make sure that there is enough margin so
that the peak current does not cause the inductor to
saturate. Peak current can be calculated as illustrated in
Equation 2:
Application Information
The MIC23163/4 is a high-performance DC/DC step-
down regulator offering a small solution size. Supporting
an output current up to 2A inside a tiny 2mm × 2mm DFN
package, the IC requires only three external components
while meeting today’s miniature portable electronic
device needs. Using the HyperLight Load (HLL) switching
scheme, the MIC23163/4 is able to maintain high
efficiency throughout the entire load range while
providing ultra-fast load transient response. The following
sections provide additional device application information.
1− VOUT /VIN
2× f × L
Eq. 2
IPEAK = I
OUT
+ VOUT
Input Capacitor
A 2.2µF ceramic capacitor or greater should be placed
close to the VIN pin and PGND pin for bypassing. A
Murata GRM188R60J475ME84D, size 0603, 4.7µF
ceramic capacitor is recommended based on
performance, size, and cost. A X5R or X7R temperature
rating is recommended for the input capacitor. Y5V
temperature rating capacitors, aside from losing most of
their capacitance over temperature, can also become
resistive at high frequencies. This reduces their ability to
filter out high-frequency noise.
As shown by Equation 2, the peak inductor current is
inversely proportional to the switching frequency and the
inductance; the lower the switching frequency or the
inductance the higher the peak current. As input voltage
increases, the peak current also increases.
The size of the inductor depends on the requirements of
the application. Refer to the “Typical Application Circuit”
and “Bill of Materials” sections for details.
DC resistance (DCR) is also important. While DCR is
inversely proportional to size, DCR can represent a
significant efficiency loss. Refer to the “Efficiency
Considerations” section for more details.
Output Capacitor
The MIC23163/4 is designed for use with a 10µF or
greater ceramic output capacitor. Increasing the output
capacitance will lower output ripple and improve load
transient response but could also increase solution size
or cost. A low equivalent series resistance (ESR) ceramic
The transition between high loads (CCM) to HLL mode is
determined by the inductor ripple current and the load
current.
output
capacitor
such
as
the
Murata
GRM188R60J106ME84D, size 0603, 10µF ceramic
capacitor is recommended based upon performance, size
and cost. Both the X7R or X5R temperature rating
capacitors are recommended. The Y5V and Z5U
temperature rating capacitors are not recommended due
to their wide variation in capacitance over temperature
and increased resistance at high frequencies.
Inductor Selection
When selecting an inductor, it is important to consider the
following factors (not necessarily in the order of
importance):
•
•
•
Rated current value
Size requirements
DC resistance (DCR)
Figure 2. Signals for High-Side Switch Drive (HSD) for TON
Control, Inductor Current, and Low-Side Switch Drive (LSD)
for TOFF Control
The MIC23163/4 is designed for use with a 0.47µH
inductor. This allows for rapid output voltage recovery
during line and load transients.
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MIC23163/4
Efficiency vs. Output Current
VOUT = 1.8V @ 25°C
In HLL mode, the inductor is charged with a fixed Ton
pulse on the high-side switch (HSD). After this, the LSD
is switched on and current falls at a rate VOUT/L. The
controller remains in HLL mode while the inductor falling
current is detected to cross approximately −50mA. When
the LSD (or TOFF) time reaches its minimum and the
inductor falling current is no longer able to reach this
−50mA threshold, the part is in CCM mode and switching
at a virtually constant frequency.
95
90
85
80
75
70
65
60
55
50
VIN = 3V
VIN = 3.6V
VIN = 5V
Once in CCM mode, the TOFF time will not vary.
Compensation
The MIC23163/4 is designed to be stable with a 0.47µH
inductor with a 10µF ceramic (X5R) output capacitor. A
feed-forward capacitor in the range of 15pF to 68pF is
essential across the top feedback resistor.
1
10
100
1000
10000
OUTPUT CURRENT (mA)
Figure 3. Efficiency under Load
Duty Cycle
Figure 3 shows an efficiency curve. From no load to
100mA, efficiency losses are dominated by quiescent
current losses, gate drive and transition losses. By using
the HLL mode, the MIC23163/4 is able to maintain high
efficiency at low output currents.
The maximum duty cycle of the MIC23163/4 is 100%,
allowing operation in dropout to extend battery life.
Efficiency Considerations
Efficiency is defined as the amount of useful output
power, divided by the amount of power supplied, as
shown in Equation 3:
Over 100mA, efficiency loss is dominated by MOSFET
RDSON and inductor losses. Higher input supply voltages
will increase the gate-to-source threshold on the internal
MOSFETs, thereby reducing the internal RDSON. This
improves efficiency by reducing DC losses in the device.
All but the inductor losses are inherent to the device. In
which case, inductor selection becomes increasingly
critical in efficiency calculations. As the inductors are
reduced in size, the DC resistance (DCR) can become
quite significant. The DCR losses can be calculated as in
Equation 4:
VOUT ×IOUT
VIN ×IIN
Efficiency % =
×100
Eq. 3
Maintaining high efficiency serves two purposes. It
reduces power dissipation in the power supply, reducing
the need for heat sinks and thermal design
considerations and it reduces consumption of current for
battery-powered applications. Reduced current draw from
a battery increases the device’s operating time and is
critical in handheld devices.
2
PDCR = IOUT × DCR
Eq. 4
There are two types of losses in switching converters; DC
losses and switching losses. DC losses are simply the
power dissipation of I2R. Power is dissipated in the high
side switch during the on cycle. Power loss is equal to the
high side MOSFET RDSON multiplied by the switch current
squared. During the off cycle, the low side N-channel
MOSFET conducts, also dissipating power. Device
operating current also reduces efficiency. The product of
the quiescent (operating) current and the supply voltage
represents another DC loss. The current required driving
the gates on and off at a constant 4MHz frequency and
the switching transitions make up the switching losses.
From that, the loss in efficiency due to inductor resistance
can be calculated as in Equation 5:
VOUT ×IOUT
Efficiency Loss = 1−
×100
VOUT ×IOUT + PDCR
Eq. 5
Efficiency loss due to DCR is minimal at light loads and
gains significance as the load is increased. Inductor
selection becomes a trade-off between efficiency and
size in this case.
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MIC23163/4
HyperLight Load Mode
As shown in Equation 6, the load at which the
MIC23163/4 transitions from HLL mode to PWM mode is
a function of the input voltage (VIN), output voltage (VOUT),
duty cycle (D), inductance (L) and frequency (f). As
shown in Figure 4, as the output current increases, the
switching frequency also increases until the MIC23163/4
goes from HLL mode to PWM mode at approximately
120mA. The MIC23163/4 will switch at a relatively
constant frequency around 4MHz once the output current
is over 120mA.
MIC23163/4 uses a minimum on and off time proprietary
control loop (PCL) patented by Micrel called HyperLight
Load (HLL). When the output voltage falls below the
regulation threshold, the error comparator begins a
switching cycle that turns the PMOS on and keeps it on
for the duration of the minimum-on-time. This increases
the output voltage. If the output voltage is over the
regulation threshold, then the error comparator turns the
PMOS off for a minimum-off-time until the output drops
below the threshold. The NMOS acts as an ideal rectifier
that conducts when the PMOS is off. Using a NMOS
switch instead of a diode allows for lower voltage drop
across the switching device when it is on. The
asynchronous switching combination between the PMOS
and the NMOS allows the control loop to work in
discontinuous mode for light load operations. In
discontinuous mode, the MIC23163/4 works in pulse
frequency modulation (PFM) to regulate the output. As
the output current increases, the off-time decreases, thus
provides more energy to the output. This switching
scheme improves the efficiency of MIC23163/4 during
light load currents by only switching when it is needed. As
the load current increases, the MIC23163/4 goes into
continuous conduction mode (CCM) and switches at a
frequency centered at 4MHz. The equation to calculate
the load when the MIC23163/4 goes into continuous
conduction mode may be approximated by Equation 6:
Switching Frequency vs.
Output Current
10000
VIN = 3.6V
1000
100
VIN = 5V
10
1
1
10
100
1000
10000
OUPUT CURRENT (mA)
Figure 4. SW Frequency vs. Output Current
(
VIN − VOUT
)
× D
Eq. 6
ILOAD
>
2L × f
Revision 2.0
July 29, 2013
15
Micrel, Inc.
MIC23163/4
Typical Application Circuit
Bill of Materials
Item
Part Number
Manufacturer Description
Qty.
C1608X5R0J475K
TDK(7)
Murata(8)
C1
4.7µF, 6.3V, X5R, Size 0603
1
GRM188R60J475KE19D
C1608X5R0J106K080AB
GRM188R60J106ME84D
GRM188R71H102MA01D
06035C102KAT2A
TDK
C2
C3
C4
L1
10µF, 6.3V, X5R, Size 0603
1nF/50V, X7R, 0603
15pF, 50V, 0603
1
1
1
1
Murata
Murata
AVX(9)
AVX
06035A150KAT2A
GRM1885C1H150JA01D
FLF3215T-R47N
Murata
TDK
0.47µH, 2.8A, 21mΩ, L3.2mm × W2.5mm × H1.55mm
0.47µH, 2.9A, 24mΩ, L3.2mm × W2.5mm × H1.55mm
301kΩ, 1%, 1/10W, Size 0603
LQH32PNR47NNC
CRCW0603301KFKEA
CRCW0603158KFKEA
CRCW0603100KFKEA
CRCW060310R0FKEA
MIC23163YMT
Murata
Vishay(10)
Vishay
Vishay
Vishay
R1
1
1
1
1
R2
158kΩ, 1%, 1/10W, Size 0603
R3, R4
R5
100kΩ, 1%, 1/10W, Size 0603
10Ω, 1%, 1/10W, Size 0603
4MHz, 2A, 100% Duty Cycle Buck Regulator with
HyperLight Load® and Power Good
U1
Micrel, Inc.(11)
1
MIC23164YMT
Notes:
7. TDK: www.tdk.com.
8. Murata: www.murata.com.
9. AVX: www.avx.com.
10. Vishay: www.vishay.com.
11. Micrel, Inc.: www.micrel.com.
Revision 2.0
July 29, 2013
16
Micrel, Inc.
MIC23163/4
PCB Layout Recommendations
Top Layer
Bottom Layer
Revision 2.0
July 29, 2013
17
Micrel, Inc.
MIC23163/4
Package Information(12) and Recommended Landing Pattern
10-Pin 2mm × 2mm DFN (MT)
Note:
12. Package information is correct as of the publication date. For updates and most current information, go to www.micrel.com.
Revision 2.0
July 29, 2013
18
Micrel, Inc.
MIC23163/4
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.
© 2013 Micrel, Incorporated.
Revision 2.0
July 29, 2013
19
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