MIC23603
4MHz PWM 6A Buck Regulator with
HyperLight Load®
Revision 1.1
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
November 5, 2013
Revision 1.1
General Description
The MIC23603 is a high-efficiency 4MHz 6A synchronous
buck regulator with HyperLight Load® mode. HyperLight
Load provides very high efficiency at light loads and ultra-
fast transient response which is 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 4mm x 5mm DFN
package saves precious board space and requires few
external components.
The MIC23603 is designed for use with a very small
inductor, down to 0.33µH, and an output capacitor as small
as 47µF that enables a sub-1mm height.
The MIC23603 has a very low quiescent current of 24µA
and achieves as high as 81% efficiency at 1mA. At higher
loads, the MIC23603 provides a constant switching
frequency around 4MHz while achieving peak efficiencies
up to 93%.
The MIC23603 is available in 20-pin 4mm x 5mm 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.
Features
• Input voltage: 2.7V to 5.5V
• 6A output current
• Up to 93% efficiency and 81% at 1mA
• 24µA typical quiescent current
• 4MHz PWM operation in continuous mode
• Ultra-fast transient response
• Power Good
• Programmable soft-start
• Low voltage output ripple
− 14mVpp ripple in HyperLight Load mode
− 5mV output voltage ripple in full PWM mode
• Fully integrated MOSFET switches
• 0.01µA shutdown current
• Thermal shutdown and current limit protection
• Output voltage as low as 0.65V
• 20-pin 4mm x 5mm DFN
• –40°C to +125°C junction temperature range
Applications
• 5V POL supplies
• µC/µP, FPGA and DSP power
• Test and measurement systems
• Barcode readers
• Set-top box, Modems, and DTV
• Distributed power systems
• Networking systems
____________________________________________________________________________________________________________
Typical Application
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MIC23603
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Ordering Information
Part Number Nominal Output
Voltage
Junction
Temp. Range Package(1) Lead Finish
MIC23603YML ADJ –40°C to +125°C 20-pin 4mm x 5mm DFN Pb-Free
Notes:
1. DFN is GREEN RoHS-compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
Pin Configuration
20-Pin 4mm x 5mm DFN (ML)
(Top View)
Pin Description
Pin Number Pin Name Pin Function
1, 2, 9-12, 19, 20 SW Switch output. Internal power MOSFET output switches.
3, 13, 14, 18 PVIN Input voltage. Connect a capacitor to ground to decouple the noise.
4 PG Power good. Connect an external resistor to a voltage source to supply a power good indicator.
5 EN Enable input. Logic high enables operation of the regulator. Logic low shuts down the device. Do
not leave floating.
6 SNS Sense input. Connect to VOUT as close to output capacitor as possible to sense output voltage.
7 FB Feedback input. Connect an external divider between VOUT and ground to program the output
voltage.
8,16 AGND Analog ground. Connect to central ground point where all high current paths meet (CIN, COUT,
PGND) for best operation.
15 SS Soft Start. Place a capacitor from this pin to ground to program the soft start time. Do not leave
floating, 2.2nF minimum CSS is required.
17 AVIN Supply voltage. Analog control circuitry. Connect to VIN through a 10Ω resistor.
EP PGND Power Ground.
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MIC23603
November 5, 2013
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Absolute Maximum Ratings(1)
Supply Voltage (VIN) ......................................................... 6V
Sense (VSNS)..................................................................... 6V
Output Switch Voltage .................................................. 6V
Enable Input Voltage (VEN) ................................ –0.3V to VIN
Storage Temperature Range .................... –65°C to +150°C
ESD Rating(3) ............................................. ESD SENSITIVE
Operating Ratings(2)
Supply Voltage (VIN) ......................................... 2.7V to 5.5V
Enable Input Voltage (VEN) .................................... 0V to VIN
Output Voltage Range (VSNS) ........................ 0.65V to 3.6V
Junction Temperature Range (TJ) ...... – 40°C ≤ TJ ≤ +125°C
Thermal Resistance
4mm x 5mm DFN-20 (θJA) .............................. 44.1°C/W
Electrical Characteristics(4)
TA = 25°C; VIN = VEN = 3.6V; VOUT = 1.8V; L = 0.33µH; COUT = 47µF x 2 unless otherwise specified.
Bold values indicate –40°C ≤ TJ ≤ +125°C, unless noted.
Parameter
Condition
Min
Typ
Max
Units
Supply Voltage Range 2.7 5.5 V
Undervoltage Lockout Threshold Turn-on 2.2 2.5 2.8 V
Undervoltage Lockout Hysteresis 270 mV
Quiescent Current IOUT = 0mA , SNS > 1.2 × VOUT Nominal 24 45 µA
Shutdown Current VEN = 0V, VIN = 5.5V 0.01 5 µA
Feedback Voltage 0.605 0.62 0.636 V
Current Limit SNS = 0.9 × VOUTNOM 6.5 12 16 A
Output Voltage Line Regulation VIN = 3.6V to 5.5V if VOUTNOM < 2.5V, ILOAD = 20mA 0.3 %/V
VIN = 4.5V to 5.5V if VOUTNOM ≥ 2.5V, ILOAD = 20mA
Output Voltage Load Regulation 20mA < ILOAD < 500mA, VIN = 3.6V if VOUTNOM < 2.5V 0.3 %
20mA < ILOAD < 500mA, VIN = 5.0V if VOUTNOM ≥ 2.5V
20mA < ILOAD < 1A, VIN = 3.6V if VOUTNOM < 2.5V 0.7 %
20mA < ILOAD < 1A, VIN = 5.0V if VOUTNOM ≥ 2.5V
PWM Switch ON-Resistance ISW = 1000mA PMOS 0.03 Ω
ISW = –1000mA NMOS 0.025
Maximum Frequency IOUT = 300mA 4 MHz
Soft Start Time VOUT = 90%, CSS = 2.2nF 1200 µs
Power Good Threshold % of VNOMINAL 85 90 95 %
Power Good Hysteresis 20 %
Power Good Pull Down VSNS = 90% VNOMINAL, IPG = 1mA 200 mV
Enable Threshold Turn-On 0.4 0.8 1.2 V
Enable Input Current 0.1 2 µA
Overtemperature Shutdown 160 °C
Overtemperature Shutdown
Hysteresis
20 °C
Notes:
1. Exceeding the absolute maximum rating can damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF.
4. Specification for packaged product only.
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MIC23603
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Typical Characteristics
0
10
20
30
40
50
60
70
80
90
100
0.0001 0.001 0.01 0.1 110
EFFICIENCY (%)
OUTPUT CURRENT (A)
Efficiency vs.
Output Current
V
IN
= 5V
L = 0.33µH
C
OUT
= 2x47µF
V
OUT
= 3.3V
V
OUT
= 2.5V
0
10
20
30
40
50
60
70
80
90
100
0.0001 0.001 0.01 0.1 110
EFFICIENCY (%)
OUTPUT CURRENT (A)
Efficiency vs.
Output Current VOUT = 1.8V
L = 0.33µH
C
OU T
= 2x47µF
V
IN
= 3.6V
V
IN
= 2.9V
V
IN
= 5V
0
10
20
30
40
50
60
70
80
90
100
0.0001 0.001 0.01 0.1 110
EFFICIENCY (%)
OUTPUT CURRENT (A)
Efficiency vs.
Output Current VOUT = 1.2V
V
IN
= 2.9V
V
IN
= 3.6V
V
IN
= 5V
L = 0.33µH
C
OUT
= 2x47µF
1.190
1.195
1.200
1.205
1.210
1.215
1.220
2.5 33.5 44.5 55.5
OUTPUT VOLTAGE (V)
INPUT VOLTAGE (V)
Output Voltage vs.
Input Voltage
LOAD = 4A
L = 0.33µH
C
OUT
= 2x47µF
LOAD = 1.5A
1.190
1.195
1.200
1.205
1.210
1.215
1.220
2.5 33.5 44.5 55.5
OUTPUT VOLTAGE (V)
INPUT VOLTAGE (V
)
Output Voltage vs.
Input Voltage
L = 0.33µH
C
OUT
= 2x47µF
LOAD = 100mA
LOAD = 10mA
1.190
1.195
1.200
1.205
1.210
1.215
1.220
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40
OUTPUT VOLTAGE (V)
OUTPUT CURRENT (A)
Output Voltage vs.
Output Current (HLL)
V
IN
= 3.6V
L = 0.33µH
C
OUT
= 2x47µF
1.180
1.185
1.190
1.195
1.200
1.205
1.210
1.215
1.220
0.5 11.5 22.5 33.5 44.5 55.5 6
OUTPUT VOLTAGE (V)
OUTPUT CURRENT (A)
Output Voltage vs.
Output Current (CCM)
V
IN
= 3.6V
L = 0.33µH
C
OUT
= 2x47µF
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
2.5 3.0 3.5 4.0 4.5 5.0 5.5
ENABLE THRESHOLD (V)
INPUT VOLTAGE (V)
Enable Thresholds vs.
Input Voltage
ENABLE OFF
ENABLE ON
V
OUT
= 1.2V
LOAD = 150mA
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
-40 -20 020 40 60 80 100 120
ENABLE THRESHOLD (V)
TEMPERATURE (°C)
Enable Thresholds vs.
Temperature
V
IN
= 3.6V
V
OUT
= 1.2V
LOAD = 150mA
TURN OFF
TURN ON
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MIC23603
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Typical Characteristics (Continued)
2.00
2.10
2.20
2.30
2.40
2.50
2.60
-40 -20 020 40 60 80 100 120
UVLO (V)
TEMPERATURE (°C)
Undervoltage Lockout vs.
Temperature
UVLO OFF
UVLO ON
0
5
10
15
20
25
30
35
40
45
2.5 33.5 44.5 55.5
PG DELAY (µs)
INPUT VOLTAGE (V)
PGOOD Delay Time vs.
Input Voltage
PG FALLING
V
OUT
= 1.2V
PG RISING
65
70
75
80
85
90
95
2.5 33.5 44.5 55.5
PGOOD THRESHOLDS (%)
INPUT VOLTAGE (V)
PGOOD Thresholds vs.
Input Voltage
PG FALLING
V
OUT
= 1.2V
PG RISING
1
10
100
1000
10000
100000
1000000
1000 10000 100000 1000000
RISE TIME (µs)
CSS (pF)
VOUT Rise Time
vs. CSS
V
IN
= 3.6V
1.190
1.192
1.194
1.196
1.198
1.200
1.202
1.204
1.206
1.208
1.210
-40 -20 020 40 60 80 100 120
OUTPUT VOLTAGE (V)
TEMPERATURE (°C)
Output Voltage vs.
Temperature
V
IN
= 3.6 V
LOAD = 20mA
0.59
0.60
0.61
0.62
0.63
0.64
0.65
-40 -20 020 40 60 80 100 120
FEEDBACK VOLTAGE (V)
TEMPERATURE (°C)
Feedback Voltage vs.
Temperature
V
OUT
= 1.2V
15
16
17
18
19
20
21
22
23
24
25
2.5 3.0 3.5 4.0 4.5 5.0 5.5
QUIESCENT (µA)
INPUT VOLTAGE (V)
Quiscent Current vs.
Input Voltage
V
OUT
= 1.8V
L = 0.33µH
C
OUT
= 2x47µF
0.1
1
10
100
1000
10000
0.0001 0.001 0.01 0.1 110
FREQUENCY (kHz)
LOAD CURRENT (A)
Switching Frequency vs.
Load Current
V
IN
= 3.6V
V
IN
= 2.9V
V
OUT
= 1.8V
L = 0.33µH
C
OUT
= 2x47µF
V
IN
=5V
6
7
8
9
10
11
12
13
2.5 3.0 3.5 4.0 4.5 5.0 5.5
CURRENT LIMIT (A)
INPUT VOLTAGE (V)
Current Limit vs.
Input Voltage
V
OUT
= 1.8V
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Typical Characteristics (Continued)
3.50
4.00
4.50
5.00
5.50
6.00
6.50
20 40 60 80 100 120 140
MAX OUPUT CURRENT (A)
AMBIENT TEMPERATURE (°C)
Maximum Output Current vs.
Ambient Temperature
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Functional Characteristics
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Functional Characteristics (Continued)
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MIC23603
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Functional Characteristics (Continued)
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Functional Diagram
Figure 1. Simplified MIC23603 Functional Block Diagram
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MIC23603
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Functional Description
PVIN
The input supply (PVIN) provides power to the internal
MOSFETs for the switch mode regulator and the driver
circuitry. The PVIN operating range is 2.7V to 5.5V, so
an input capacitor, with a minimum voltage rating of
6.3V, is recommended. Because of the high switching
speed, a minimum 10µF bypass capacitor placed close
to VIN and the power ground (PGND) pin is required.
See the PCB Layout Recommendations for details.
AVIN
Analog VIN (AVIN) provides power to the internal control
and analog circuitry. AVIN and PVIN must be tied
together. A 10Ω resistor is recommended to minimize
noise coupling from PVIN. Consider the layout carefully
to reduce high frequency switching noise caused by VIN
before reaching AVIN. Micrel recommends placing a 1µF
capacitor as close to AVIN as possible. See PCB Layout
Recommendations for details.
EN
A logic high signal on the enable pin activates the
device’s output voltage. A logic low signal on the enable
pin deactivates the output and reduces supply current to
0.01µA. The MIC23603 features built-in soft-start
circuitry that reduces inrush current and prevents the
output voltage from overshooting at start-up. Do not
leave EN floating.
SW
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. Because of the high
speed switching on this pin, route the switch node away
from sensitive nodes whenever possible.
SNS
The sense (SNS) pin is connected to the device’s output
to provide feedback to the control circuitry. Place the
SNS connection close to the output capacitor. See PCB
Layout Recommendations for details.
PG
The power good (PG) pin is an open-drain output that
indicates logic high when the output voltage is typically
above 90% of its steady state voltage. A pull-up resistor
of more than 5kΩ should be connected from PG to VOUT.
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
(PGND) loop. See PCB Layout Recommendations for
details. Placing a 3Ω resistor between AGND and PGND
reduces ground noise.
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. See
PCB Layout Recommendations for details.
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 250x103 x ln(10) x CSS.
For example, for CSS = 2.2nF, Trise ~ 1.26ms. See the
Typical Characteristics curve for a graphical guide. The
minimum recommended value for CSS is 2.2nF.
FB
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
0.62V reference within the regulation loop.
Use Equation 1 to program the output voltage between
0.65V and 3.6V:
+×= R4
R3
1VV
REFOUT
Eq. 1
where: R3 is the top resistor, R4 is the bottom resistor.
VOUT R3 R4
1.2V 274kΩ 294kΩ
1.5V 316kΩ 221kΩ
1.8V 560kΩ 294kΩ
2.5V 324kΩ 107kΩ
3.3V 464kΩ 107kΩ
Table 1. Example Feedback Resistor Values
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MIC23603
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Application Information
The MIC23603 is a high-performance DC/DC step down
regulator offering a small solution size. Because it
supports an output current up to 6A inside a tiny 4mm x
5mm DFN package and requires only three external
components, the MIC23603 meets today’s miniature
portable electronic device needs. Using the HyperLight
Load switching scheme, the MIC23603 maintains high
efficiency throughout the entire load range while
providing ultra-fast load transient response. The
following sections provide additional device application
information.
Input Capacitor
Place a 10µF ceramic capacitor or greater close to the
VIN pin and PGND/GND pin for bypassing. Micrel
recommends the TDK C1608X5R0J106K, size 0603,
10µF ceramic capacitor based upon performance, size,
and cost. An 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.
Output Capacitor
The MIC23603 was designed for use with a 47µF or
greater ceramic output capacitor. Increasing the output
capacitance lowers output ripple and improves load
transient response, but could increase solution size or
cost. A low equivalent series resistance (ESR) ceramic
output capacitor such as the TDK C3216X6S1A476M,
size 1206, 47µF 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 because of their wide variation in
capacitance over temperature and increased resistance
at high frequencies.
Inductor Selection
When selecting an inductor, consider the following
factors (not necessarily in order of importance):
• Inductance
• Rated current value
• Size requirements
• DC resistance (DCR)
The MIC23603 was designed for use with a 0.33µH to
1µH inductor. For faster transient response, a 0.33µH
inductor yields the best result. For lower output ripple, a
1µH inductor is recommended.
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. Make sure that 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
follows:
××
−
+= Lf2
/VV1
VII IN
OUT
OUTOUTPEAK
Eq. 2
As Equation 2 shows, 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
Schematic and Bill of Materials for details.
DC resistance (DCR) is also important. While DCR is
inversely proportional to size, it can represent a
significant efficiency loss. See Efficiency Considerations.
Compensation
The MIC23603 is designed to be stable with a 0.33µH to
1µH inductor with a minimum of 47µF ceramic (X5R)
output capacitor. A feedforward capacitor (CFF) in the
range of 33pF to 68pF is recommended across the top
feedback resistor to reduce the effects of parasitic
capacitance and improve transient performance.
Duty Cycle
The typical maximum duty cycle of the MIC23603 is
80%.
Efficiency Considerations
Efficiency is defined as the amount of useful output
power, divided by the amount of power supplied.
100
IV
IV
%Efficiency
ININ
OUTOUT ×
×
×
=
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 current consumption for
battery powered applications. Reduced current draw
from a battery increases the device’s operating time and
is critical in hand-held devices.
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.
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Device operating current also reduces efficiency. The
product of the quiescent (operating) current and the
supply voltage represents another DC loss. The current
needed to drive the gates on and off at a constant 4MHz
frequency and the switching transitions make up the
switching losses.
0
10
20
30
40
50
60
70
80
90
100
0.0001 0.001 0.01 0.1 110
EFFICIENCY (%)
OUTPUT CURRENT (A)
Efficiency vs.
Output Current VOUT = 2.5V
V
IN
= 5V
L = 0.33µH
COUT = 2x47µF
Figure 2. Efficiency Under Load
Figure 2 shows an efficiency curve, from no load to
300mA. Efficiency losses are dominated by quiescent
current losses, gate drive, and transition losses. By
using the HyperLight Load mode, the MIC23603 can
maintain high efficiency at low output currents.
Over 300mA, 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, which reduces the internal RDSON.
This improves efficiency by reducing DC losses in the
device. All but the inductor losses are inherent to the
device. In this case, inductor selection becomes
increasingly critical in efficiency calculations. As the
inductors get smaller, the DC resistance (DCR) can
become quite significant. The DCR losses can be
calculated as follows:
PDCR = IOUT
2 × DCR Eq. 4
From that, the loss in efficiency due to inductor
resistance can be calculated as follows:
100
P
IV
IV
1Loss
Efficiency
DCROUTOUT
OUTOUT ×
+×
×
−=
Eq. 5
Efficiency loss caused by DCR is minimal at light loads
and gains significance as the load is increased. Inductor
selection becomes a trade-off between efficiency and
size.
HyperLight Load® Mode
MIC23603 uses a minimum on and off time proprietary
control loop (patented by Micrel). 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 an 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 MIC23603 works
in pulse frequency modulation (PFM) to regulate the
output. As the output current increases, the off-time
decreases, which provides more energy to the output.
This switching scheme improves the efficiency of
MIC23603 during light load currents by switching only
when needed. As the load current increases, the
MIC23603 goes into continuous conduction mode (CCM)
and switches at a frequency centered at 4MHz. The load
when the MIC23603 goes into continuous conduction
mode may be approximated by the following formula:
×
×−
>fL2
D
)VV
(
IOUTIN
LOAD
Eq. 6
As shown in the previous equation, the load at which
MIC23603 transitions from HyperLight Load 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 3, as the Output
Current increases, the switching frequency also
increases, until the MIC23603 goes from HyperLight
Load mode to PWM mode at approximately 300mA. The
MIC23603 switches a relatively constant frequency
around 4MHz after the output current is over 300mA.
0.1
1
10
100
1000
10000
0.0001 0.001 0.01 0.1 110
FREQUENCY (kHz)
LOAD CURRENT (A)
Switching Frequency vs.
Load Current
V
IN
= 3.6V
V
IN
= 2.9V
V
OUT
= 1.8V
L = 0.33µH
C
OUT
= 2x47µF
V
IN
=5V
Figure 3. SW Frequency vs. Output Current
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MIC23603
November 5, 2013
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Typical Application Schematic
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Bill of Materials
Item Part Number Manufacturer Description Qty
C1, C2, C7, C8 06036D106MAT2A AVX
(1)
10µF/6.3V,X5R,0603 4
GRM188R60J106ME47D Murata
(2)
C3, C11, C14 04026D105KAT2A AVX 1µF/6.3V,X5R,0402 4
GRM155R60J105KE19D Murata
C4
04025A223JAT2A AVX
2.2nF/50V,0402 1 GRM1555C1H223JA01D Murata
C1005C0G1H223J TDK
C5,C6 12066D476MAT2A AVX 47µF/6.3V,X5R,1206 2
GRM31CR60J476ME19L Murata
C10 04025A680JAT2A AVX 68pF, 50V, NPO,0402 1
GRM1555C1H680JZ01D Murata
C12 GRM155R60J475ME47D Murata 4.7µF, 6.3V, X5R, 0402 1
04026D475KAT2A AVX
C13 04026C104KAT2A AVX 0.1µF/6.3V,X7R,0402 1
GRM155R70J104KA01D Murata
L1 IHLP2020CZERR33M01 Vishay
(3)
0.33µH, 13.7A , 4.3mΩ 1
CDMC6D28NP-R30MC Sumida
(4)
0.3µH, 16.1A, 2.7mΩ
R1, R2 CRCW0402100KFKED Vishay/Dale 100K, 1%, 1/16W, 0402 2
R3 CRCW0402560KFKEA Vishay/Dale 560KΩ, 1%, 1/6W, 0402 1
R4 CRCW0402294KFKEA Vishay/Dale 294KΩ, 1%, 1/10W, 0402 1
R5 CRCW040210R0FKED Vishay/Dale 10Ω, 1%, 1/16W, 0402 1
U1 MIC23603YML Micrel , Inc.(5) 4MHz PWM 6A Buck Regulator with
HyperLight Load® 1
Notes:
1. AVX: www.avx.com.
2. Murata: www.murata.com.
3. Vishay: www.vishay.com.
4. Sumida: www.sumida.com.
5. Micrel, Inc.: www.micrel.com.
Micrel Inc.
MIC23603
November 5, 2013
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PCB Layout Recommendations
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Micrel Inc.
MIC23603
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Micrel Inc.
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Recommended Land Pattern
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