MIC23603

MIC23603
4MHz PWM 6A Buck Regulator with
HyperLight Load®
Revision 1.1
General Description
Features
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 ultrafast 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.
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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
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
Micrel Inc.
MIC23603
Ordering Information
Part Number
Nominal Output
Voltage
Junction
Temp. Range
MIC23603YML
ADJ
–40°C to +125°C
Package
(1)
20-pin 4mm x 5mm DFN
Lead Finish
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
1, 2, 9-12, 19, 20
SW
Pin Function
3, 13, 14, 18
PVIN
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.
Switch output. Internal power MOSFET output switches.
Input voltage. Connect a capacitor to ground to decouple the noise.
17
AVIN
Supply voltage. Analog control circuitry. Connect to VIN through a 10Ω resistor.
EP
PGND
Power Ground.
November 5, 2013
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Micrel Inc.
MIC23603
Absolute Maximum Ratings(1)
Operating Ratings(2)
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
(3)
ESD Rating ............................................. ESD SENSITIVE
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
Undervoltage Lockout Threshold
2.2
Turn-on
Undervoltage Lockout Hysteresis
IOUT = 0mA , SNS > 1.2 × VOUT Nominal
Shutdown Current
VEN = 0V, VIN = 5.5V
Feedback Voltage
Current Limit
SNS = 0.9 × VOUTNOM
Output Voltage Line Regulation
VIN = 3.6V to 5.5V if VOUTNOM < 2.5V, ILOAD = 20mA
Units
5.5
V
2.8
V
45
µA
0.01
5
µA
0.605
0.62
0.636
V
6.5
12
16
A
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
0.3
%/V
0.3
%
0.7
%
ISW = 1000mA PMOS
0.03
ISW = –1000mA NMOS
0.025
Maximum Frequency
IOUT = 300mA
Soft Start Time
VOUT = 90%, CSS = 2.2nF
Power Good Threshold
% of VNOMINAL
mV
24
VIN = 4.5V to 5.5V if VOUTNOM ≥ 2.5V, ILOAD = 20mA
PWM Switch ON-Resistance
2.5
Max
270
Quiescent Current
Output Voltage Load Regulation
Typ
2.7
Supply Voltage Range
Ω
4
MHz
1200
µs
85
90
Power Good Hysteresis
95
%
20
Power Good Pull Down
VSNS = 90% VNOMINAL, IPG = 1mA
Enable Threshold
Turn-On
%
200
mV
0.8
1.2
V
Enable Input Current
0.1
2
µA
Overtemperature Shutdown
160
°C
Overtemperature Shutdown
Hysteresis
20
°C
0.4
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
Typical Characteristics
Efficiency vs.
Output Current
VOUT = 3.3V
60
50
40
30
VIN = 5V
L = 0.33µH
COUT = 2x47µF
20
10
0
0.0001
0.001
0.01
0.1
1
100
90
90
80
80
70
50
VIN = 2.9V
40
30
L = 0.33µH
COU T= 2x47µF
20
10
0
0.0001
10
0.001
0.01
0.1
1
70
60
VIN = 3.6V
50
30
20
L = 0.33µH
COUT = 2x47µF
10
0
0.0001
10
1
Output Voltage vs.
Input Voltage
Output Voltage vs.
Input Voltage
Output Voltage vs.
Output Current (HLL)
1.215
1.210
LOAD = 4A
1.205
LOAD = 1.5A
1.200
L = 0.33µH
COUT = 2x47µF
1.195
3
3.5
4
4.5
5
1.210
LOAD = 100mA
1.205
1.200
LOAD = 10mA
1.195
1.190
5.5
L = 0.33µH
COUT = 2x47µF
2.5
3
1.00
1.215
0.95
ENABLE THRESHOLD (V)
1.220
1.210
1.205
1.200
1.195
1.190
VIN = 3.6V
L = 0.33µH
COUT = 2x47µF
2
2.5
3
3.5
4
4.5
OUTPUT CURRENT (A)
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4
4.5
5
1.205
1.200
VIN = 3.6V
L = 0.33µH
COUT = 2x47µF
1.195
1.190
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40
5.5
5
OUTPUT CURRENT (A)
Enable Thresholds vs.
Temperature
Enable Thresholds vs.
Input Voltage
Output Voltage vs.
Output Current (CCM)
1.5
3.5
5.5
1.00
ENABLE ON
0.90
0.85
0.80
ENABLE OFF
0.75
0.70
VOUT = 1.2V
LOAD = 150mA
0.65
6
0.60
10
1.210
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
1.185
OUTPUT VOLTAGE (V)
1.215
1
0.1
OUTPUT CURRENT (A)
1.215
0.5
0.01
OUTPUT CURRENT (A)
1.220
1.180
0.001
OUTPUT CURRENT (A)
1.220
2.5
VIN = 5V
VIN = 2.9V
40
1.220
1.190
OUTPUT VOLTAGE (V)
VIN = 5V
VIN = 3.6V
60
ENABLE THRESHOLD (V)
OUTPUT VOLTAGE (V)
EFFICIENCY (%)
VOUT = 2.5V
70
OUTPUT VOLTAGE (V)
EFFICIENCY (%)
80
100
EFFICIENCY (%)
100
90
Efficiency vs.
Output Current VOUT = 1.2V
Efficiency vs.
Output Current VOUT = 1.8V
2.5
3.0
3.5
4.0
4.5
INPUT VOLTAGE (V)
4
5.0
5.5
0.95
0.90
TURN ON
0.85
0.80
0.75
0.70
0.65
0.60
VIN = 3.6V
VOUT = 1.2V
LOAD = 150mA
-40
-20
0
TURN OFF
20
40
60
80
100
120
TEMPERATURE (°C)
Revision 1.1
Micrel Inc.
MIC23603
Typical Characteristics (Continued)
PG RISING
40
2.50
PGOOD THRESHOLDS (%)
UVLO ON
35
PG DELAY (µs)
UVLO (V)
95
45
2.60
2.40
UVLO OFF
2.30
2.20
30
25
20
PG FALLING
15
10
2.10
2.00
PGOOD Thresholds vs.
Input Voltage
PGOOD Delay Time vs.
Input Voltage
Undervoltage Lockout vs.
Temperature
VOUT = 1.2V
5
-40
-20
0
20
40
60
80
100
0
120
2.5
3
3.5
4
4.5
5
85
80
75
PG FALLING
70
65
5.5
PG RISING
90
VOUT = 1.2V
2.5
3
3.5
4
4.5
5
TEMPERATURE (°C)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
VOUT Rise Time
vs. CSS
Output Voltage vs.
Temperature
Feedback Voltage vs.
Temperature
1.210
1000000
5.5
0.65
OUTPUT VOLTAGE (V)
RISE TIME (µs)
100000
10000
1000
100
10
10000
100000
1.206
1.204
1.202
1.200
1.198
1.196
VIN = 3.6 V
LOAD = 20mA
1.194
1.192
VIN = 3.6V
1
1000
FEEDBACK VOLTAGE (V)
1.208
1000000
1.190
-40
-20
0
20
40
60
80
100
CSS (pF)
TEMPERATURE (°C)
Quiscent Current vs.
Input Voltage
Switching Frequency vs.
Load Current
120
20
19
18
VOUT = 1.8V
L = 0.33µH
COUT = 2x47µF
17
16
15
2.5
3.0
3.5
4.0
4.5
INPUT VOLTAGE (V)
November 5, 2013
5.0
100
VIN = 3.6V
10
0.1
0.0001
VOUT = 1.2V
-40
-20
0
20
40
60
80
100
120
12
VIN = 2.9V
1
5.5
0.60
Current Limit vs.
Input Voltage
CURRENT LIMIT (A)
FREQUENCY (kHz)
QUIESCENT (µA)
21
0.61
13
1000
22
0.62
TEMPERATURE (°C)
24
23
0.63
0.59
10000
25
0.64
VIN=5V
0.001
0.01
VOUT = 1.8V
L = 0.33µH
COUT = 2x47µF
0.1
LOAD CURRENT (A)
5
1
11
10
9
8
VOUT = 1.8V
7
10
6
2.5
3.0
3.5
4.0
4.5
5.0
5.5
INPUT VOLTAGE (V)
Revision 1.1
Micrel Inc.
MIC23603
Typical Characteristics (Continued)
Maximum Output Current vs.
Ambient Temperature
MAX OUPUT CURRENT (A)
6.50
6.00
5.50
5.00
4.50
4.00
3.50
20
40
60
80
100
120
140
AMBIENT TEMPERATURE (°C)
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MIC23603
Functional Characteristics
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MIC23603
Functional Characteristics (Continued)
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MIC23603
Functional Characteristics (Continued)
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Micrel Inc.
MIC23603
Functional Diagram
Figure 1. Simplified MIC23603 Functional Block Diagram
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MIC23603
Functional Description
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.
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.
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.
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.
SS
The soft start (SS) pin is used to control the output
voltage ramp up time. The approximate equation for the
3
ramp time in seconds is 250x10 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.
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.
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:
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.
R3 

VOUT = VREF × 1 +

R4 

where: R3 is the top resistor, R4 is the bottom resistor.
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.
November 5, 2013
Eq. 1
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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Micrel Inc.
MIC23603
Application Information
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:
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.

 1 − VOUT /VIN
IPEAK = IOUT + VOUT 
 2× f ×L

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.
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.
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.
V
×I
Efficiency % =  OUT OUT
 VIN × IIN
Inductor Selection
When selecting an inductor, consider the following
factors (not necessarily in order of importance):
Inductance
•
Rated current value
•
Size requirements

 × 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 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
2
the power dissipation of I R. 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.
• 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
November 5, 2013
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.
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.
•



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MIC23603
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.
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 minimumoff-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:
Efficiency vs.
Output Current VOUT = 2.5V
100
90
EFFICIENCY (%)
80
70
60
50
40
30
VIN = 5V
L = 0.33µH
COUT = 2x47µF
20
10
0
0.0001
0.001
0.01
0.1
1
10
OUTPUT CURRENT (A)
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:
2
PDCR = IOUT × DCR
 ( V − VOUT ) × D 

ILOAD >  IN
2L × f


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.
Switching Frequency vs.
Load Current
10000
Eq. 4
From that, the loss in efficiency due to inductor
resistance can be calculated as follows:

 × 100 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.
100
VIN = 3.6V
10
1
0.1
0.0001
VIN=5V
0.001
0.01
VOUT = 1.8V
L = 0.33µH
COUT = 2x47µF
0.1
1
10
LOAD CURRENT (A)
®
HyperLight Load Mode
MIC23603 uses a minimum on and off time proprietary
control loop (patented by Micrel). When the output
November 5, 2013
VIN = 2.9V
1000
FREQUENCY (kHz)
 
VOUT × IOUT
Efficiency Loss = 1 − 
  VOUT × IOUT + PDCR
Eq. 6
Figure 3. SW Frequency vs. Output Current
13
Revision 1.1
Micrel Inc.
MIC23603
Typical Application Schematic
November 5, 2013
14
Revision 1.1
Micrel Inc.
MIC23603
Bill of Materials
Item
C1, C2, C7, C8
C3, C11, C14
Part Number
06036D106MAT2A
GRM188R60J106ME47D
04026D105KAT2A
GRM155R60J105KE19D
04025A223JAT2A
C4
C5,C6
C10
C12
C13
L1
GRM1555C1H223JA01D
Manufacturer
Murata
Murata
Murata
TDK
AVX
Murata
AVX
GRM1555C1H680JZ01D
Murata
GRM155R60J475ME47D
Murata
04026D475KAT2A
04026C104KAT2A
GRM155R70J104KA01D
IHLP2020CZERR33M01
CDMC6D28NP-R30MC
Qty
10µF/6.3V,X5R,0603
4
1µF/6.3V,X5R,0402
4
2.2nF/50V,0402
1
47µF/6.3V,X5R,1206
2
68pF, 50V, NPO,0402
1
4.7µF, 6.3V, X5R, 0402
1
0.1µF/6.3V,X7R,0402
1
AVX
12066D476MAT2A
04025A680JAT2A
(2)
AVX
C1005C0G1H223J
GRM31CR60J476ME19L
Description
(1)
AVX
AVX
AVX
Murata
(3)
Vishay
Sumida
0.33µH, 13.7A , 4.3mΩ
(4)
0.3µH, 16.1A, 2.7mΩ
1
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
4MHz PWM 6A Buck Regulator with
®
HyperLight Load
1
U1
MIC23603YML
(5)
Micrel , Inc.
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.
November 5, 2013
15
Revision 1.1
Micrel Inc.
MIC23603
PCB Layout Recommendations
Top Layer
Second Layer
November 5, 2013
16
Revision 1.1
Micrel Inc.
MIC23603
PCB Layout Recommendations (Continued)
Third Layer
Bottom Layer
November 5, 2013
17
Revision 1.1
Micrel Inc.
MIC23603
Package Information(1)
Note:
1.
20-Pin 4mm x 5mm DFN (ML)
Package information is correct as of the publication date. For updates and most current information, go to www.micrel.com.
November 5, 2013
18
Revision 1.1
Micrel Inc.
MIC23603
Recommended Land Pattern
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
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© 2013 Micrel, Incorporated.
November 5, 2013
19
Revision 1.1