MCP16301
High-Performance Low-Noise
5V Output Buck Converter
Evaluation Board
User’s Guide
2012-2013 Microchip Technology Inc.
DS50002063B
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ISBN: 978-1-62077-420-5
QUALITY MANAGEMENT SYSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
DS50002063B-page 2
Microchip received ISO/TS-16949:2009 certification for its worldwide
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and manufacture of development systems is ISO 9001:2000 certified.
2012-2013 Microchip Technology Inc.
Object of Declaration: MCP16301 High-Performance Low-Noise 5V Output
Buck Converter Evaluation Board User’s Guide
2012-2013 Microchip Technology Inc.
DS50002063B-page 3
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
Table of Contents
Preface ........................................................................................................................... 5
Introduction............................................................................................................ 5
Document Layout .................................................................................................. 5
Conventions Used in this Guide ............................................................................ 6
Recommended Reading........................................................................................ 7
The Microchip Web Site ........................................................................................ 7
Customer Support ................................................................................................. 7
Document Revision History ................................................................................... 7
Chapter 1. Product Overview
1.1 Introduction ..................................................................................................... 9
1.2 MCP16301 Short Overview ............................................................................ 9
1.3 What Is the MCP16301 High Performance Low Noise 5V Buck Converter
Evaluation Board? .................................................................................. 11
1.4 MCP16301 High Performance Low Noise 5V Buck Converter
Evaluation Board Kit Contents ................................................................ 11
Chapter 2. Installation and Operation
2.1 Introduction ................................................................................................... 13
2.2 Getting Started ............................................................................................. 14
Appendix A. Schematic and Layouts
A.1 Introduction .................................................................................................. 21
A.2 Board – Schematic ....................................................................................... 22
A.3 Board – Top Silk And Copper ...................................................................... 23
A.4 Board – Mid Inner Layer 1 ........................................................................... 24
A.5 Board – Mid Inner Layer 2 ........................................................................... 25
A.6 Board – Bottom Copper and Pads ............................................................... 26
Appendix B. Bill of Materials (BOM).......................................................................... 27
Worldwide Sales and Service .................................................................................... 28
2012-2013 Microchip Technology Inc.
DS50002063B-page 4
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
Preface
NOTICE TO CUSTOMERS
All documentation becomes dated, and this manual is no exception. Microchip tools and
documentation are constantly evolving to meet customer needs, so some actual dialogs
and/or tool descriptions may differ from those in this document. Please refer to our web site
(www.microchip.com) to obtain the latest documentation available.
Documents are identified with a “DS” number. This number is located on the bottom of each
page, in front of the page number. The numbering convention for the DS number is
“DSXXXXXA”, where “XXXXX” is the document number and “A” is the revision level of the
document.
For the most up-to-date information on development tools, see the MPLAB® IDE online help.
Select the Help menu, and then Topics to open a list of available online help files.
INTRODUCTION
This chapter contains general information that will be useful to know before using the
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board. Items
discussed in this chapter include:
•
•
•
•
•
•
Document Layout
Conventions Used in this Guide
Recommended Reading
The Microchip Web Site
Customer Support
Document Revision History
DOCUMENT LAYOUT
This document describes how to use the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board as a development tool to emulate and debug firmware on a target board. The manual layout is as follows:
• Chapter 1. “Product Overview” – Important information about the MCP16301
High-Performance Low-Noise 5V Buck Converter Evaluation Board
• Chapter 2. “Installation and Operation” – Includes instructions on how to get
started with the MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board and a description of the user’s guide
• Appendix A. “Schematic and Layouts” – Shows the schematic and layout
diagrams for the MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board
• Appendix B. “Bill of Materials (BOM)” – Lists the parts used to build the
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
2012-2013 Microchip Technology Inc.
DS50002063B-page 5
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
CONVENTIONS USED IN THIS GUIDE
This manual uses the following documentation conventions:
DOCUMENTATION CONVENTIONS
Description
Arial font:
Italic characters
Initial caps
Quotes
Underlined, italic text with
right angle bracket
Bold characters
N‘Rnnnn
Text in angle brackets < >
Courier New font:
Plain Courier New
Represents
Examples
Referenced books
Emphasized text
A window
A dialog
A menu selection
A field name in a window or
dialog
A menu path
MPLAB® IDE User’s Guide
...is the only compiler...
the Output window
the Settings dialog
select Enable Programmer
“Save project before build”
A dialog button
A tab
A number in verilog format,
where N is the total number of
digits, R is the radix and n is a
digit.
A key on the keyboard
Click OK
Click the Power tab
4‘b0010, 2‘hF1
Italic Courier New
Sample source code
Filenames
File paths
Keywords
Command-line options
Bit values
Constants
A variable argument
Square brackets [ ]
Optional arguments
Curly brackets and pipe
character: { | }
Ellipses...
Choice of mutually exclusive
arguments; an OR selection
Replaces repeated text
Represents code supplied by
user
DS50002063B-page 6
File>Save
Press <Enter>, <F1>
#define START
autoexec.bat
c:\mcc18\h
_asm, _endasm, static
-Opa+, -Opa0, 1
0xFF, ‘A’
file.o, where file can be
any valid filename
mcc18 [options] file
[options]
errorlevel {0|1}
var_name [,
var_name...]
void main (void)
{ ...
}
2012-2013 Microchip Technology Inc.
Preface
RECOMMENDED READING
This user's guide describes how to use the MCP16301 High-Performance Low-Noise
5V Buck Converter Evaluation Board. Other useful documents are listed below. The
following Microchip documents are available and recommended as supplemental
reference resources.
• MCP16301 Data Sheet – “High-Voltage Input Integrated Switch Step-Down
Regulator” (DS25004)
• MCP16301 High-Voltage Buck-Boost Demo Board User’s Guide (DS52020)
• MCP16301 High-Voltage Buck Converter 600 mA Demo Board User’s Guide
(DS51978)
THE MICROCHIP WEB SITE
Microchip provides online support via our web site at www.microchip.com. This web
site is used as a means to make files and information easily available to customers.
Accessible by using your favorite Internet browser, the web site contains the following
information:
• Product Support – Data sheets and errata, application notes and sample
programs, design resources, user’s guides and hardware support documents,
latest software releases and archived software
• General Technical Support – Frequently Asked Questions (FAQs), technical
support requests, online discussion groups, Microchip consultant program
member listing
• Business of Microchip – Product selector and ordering guides, latest Microchip
press releases, listing of seminars and events, listings of Microchip sales offices,
distributors and factory representatives
CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
•
•
•
•
Distributor or Representative
Local Sales Office
Field Application Engineer (FAE)
Technical Support
Customers should contact their distributor, representative or field application engineer
(FAE) for support. Local sales offices are also available to help customers. A listing of
sales offices and locations is included in the back of this document.
Technical support is available through the web site at:
http://www.microchip.com/support.
DOCUMENT REVISION HISTORY
Revision B (August 2013)
• Updated the board layout in Figure 2-2.
• Updated the A.3 “Board – Top Silk And Copper” and A.6 “Board – Bottom
Copper and Pads” layouts in Appendix A. “Schematic and Layouts”.
• Updated Appendix B. “Bill of Materials (BOM)”.
Revision A (June 2012)
• Initial Release of this Document.
2012-2013 Microchip Technology Inc.
DS50002063B-page 7
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
NOTES:
DS50002063B-page 8
2012-2013 Microchip Technology Inc.
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
Chapter 1. Product Overview
1.1
INTRODUCTION
This chapter provides an overview of the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board and covers the following topics:
• MCP16301 Short Overview
• What Is the MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board?
• MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
Kit Contents
1.2
MCP16301 SHORT OVERVIEW
The MCP16301 device is a highly integrated, high-efficiency, fixed frequency,
step-down DC-DC converter in a popular 6-pin SOT-23 package, that operates from
input voltage sources up to 30V. Integrated features include a high-side switch, fixed
frequency peak current mode control, internal compensation, peak current limit and
overtemperature protection.
All control system components necessary for stable operation over the entire device
operating range are integrated.
High-converter efficiency is achieved by integrating the current-limited, low-resistance,
high-speed N-Channel MOSFET and associated drive circuitry. High-switching frequency minimizes the size of the external filtering components, resulting in a small
solution size.
The MCP16301 is a high-input voltage step-down regulator, capable of supplying a
maximum of 600 mA to a regulated output voltage from 2.0V to 15V. An integrated precise 0.8V reference combined with an external resistor divider sets the desired converter output voltage. The internal reference voltage rate of rise is controlled during
startup, minimizing the output voltage overshoot and the inrush current.
The internally trimmed 500 kHz oscillator provides a fixed frequency, while the peak
current mode control architecture varies the duty cycle for output voltage regulation. An
internal floating driver is used to turn the high side integrated N-Channel MOSFET on
and off. The power for this driver is derived from an external boost capacitor whose
energy is supplied from a fixed voltage ranging between 3.0V and 5.5V, typically the
output voltage of the converter. For applications with 5.5V < VOUT < 15V and
VIN < 30V, an alternative boost supply must be used (from input derived, output derived
or an auxiliary system voltage). For more information and examples, see the
MCP16301 data sheet.
The EN input is used to enable and disable the device. If disabled, the MCP16301
device consumes 7 µA (typical) from the input. An integrated Under Voltage Lockout
(UVLO) prevents the converter from starting until the input voltage is high enough for
normal operation. The converter will typically start at 3.5V and operate down to 3.0V.
An overtemperature protection limits the silicon die temperature to +150°C by turning
the converter off. The normal switching resumes at +120°C.
2012-2013 Microchip Technology Inc.
DS50002063B-page 9
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
1N4448
VIN
4.5V To 30V
CBOOST L1
100 nF 15 µH
BOOST
SW
VIN
CIN
22 µF
VOUT
3.3V @ 600 mA
40V
Schottky
Diode
EN
COUT
22 µF
31.2 K
VFB
GND
FIGURE 1-1:
1.2.1
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
DS50002063B-page 10
10 K
Typical MCP16301 3.3V OUT Application.
MCP16301 Features
Up to 96% Typical Efficiency
Input Voltage Range: 4.0V to 30V
Output Voltage Range: 2.0V to 15V
2% Output Voltage Accuracy
600 mA Output Current
Quiescent Current (Switching Mode, No Load): 2 mA Typical
Quiescent Current (Shutdown, EN = 0): 7 µA Typical
500 kHz Fixed Frequency
Peak Current Mode Control
Internal Compensation
Internal Soft-Start
Cycle-by-Cycle Peak Current Limit
Undervoltage Lockout (UVLO): 3.5V to Start, 3.0V to Stop
Overtemperature Protection
Package type: SOT-23-6
2012-2013 Microchip Technology Inc.
Product Overview
1.3
WHAT IS THE MCP16301 HIGH-PERFORMANCE LOW-NOISE 5V BUCK
CONVERTER EVALUATION BOARD?
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board is
designed to operate from a 6V to 30V input and regulate the output to 5V, while delivering a maximum 600 mA of load current.
The evaluation board is optimized for a high-efficiency and low-output noise and ripple,
especially at 12V Input and 100 mA load current. Because the MCP16301 is switching
fast to achieve high efficiency, high-frequency noise is generated and may affect some
RF systems. This evaluation board demonstrates a low-noise, high-performance
design.
RBOOST CBOOST
82R
BOOST
BOOST Diode
100 nF
L 22 µH
VOUT = 5V
SW
CIN
22 µF
VIN
EN
CSnubber
120 pF
RSnubber
4R7
MCP16301
VIN = 12V Input
RT
52k3
COUT
FB
GND
22 µF
RB
10k
FIGURE 1-2:
MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board Block Diagram.
1.4
MCP16301 HIGH-PERFORMANCE LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD KIT CONTENTS
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board kit
includes:
• MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
• Important Information Sheet
2012-2013 Microchip Technology Inc.
DS50002063B-page 11
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
NOTES:
DS50002063B-page 12
2012-2013 Microchip Technology Inc.
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
Chapter 2. Installation and Operation
2.1
INTRODUCTION
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board is
used to demonstrate a high-voltage input DC-DC converter design, that can deliver
high efficiency, while minimizing high-frequency switching noise. The board steps down
high-input voltages, up to 30V, to a low-output voltage, having more than 90% efficiency
and a minimum of 30 mV output ripple.
High-frequency input/output noise generated by the switching converters can reach
high-noise levels that interfere with other devices powered from the same source. The
high amplitude of high-frequency noise can disturb some RF systems.
High efficiency is achieved with the MCP16301 buck converter by switching the integrated N-Channel MOSFET at a high speed. This high speed can cause disturbances
to other system components if the high-speed switching edges of the converter are not
minimized. The designer must be concerned with:
• good PCB layout practice
• choosing high-quality shielded inductors and low Equivalent Series Resistance
(ESR) capacitors
• choosing an RC snubber or a RBOOST resistor to properly limit the speed of the
internal N-Channel MOSFET switch (see Figure 1-2).
The evaluation board is optimized for 12V Input and 100 mA load.
2.1.1
MCP16301 High-Performance Low-Noise 5V Buck Converter
Evaluation Board Features
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board
has the following key features:
•
•
•
•
•
•
Input Voltage: 6 to 30V
Output Voltage: 5V
Output Capability: 600 mA Load Current
Output Ripple Plus Noise: 30 mVp-p @ 12V Input and 100 mA Load
Low-Radiated Noise
Efficiency: Up to 91% @ 12V Input (see Figure 2-1)
2012-2013 Microchip Technology Inc.
DS50002063B-page 13
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
90
Efficiency (%)
80
70
60
50
40
0
FIGURE 2-1:
2.2
100
200
300
IOUT (mA)
400
500
600
Efficiency vs. Load Current at 12V Input.
GETTING STARTED
The MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board is
fully assembled and tested to evaluate and demonstrate the MCP16301 design.
2.2.1
Power Input and Output Connection
2.2.1.1
POWERING THE MCP16301 HIGH-PERFORMANCE LOW-NOISE 5V
BUCK CONVERTER EVALUATION BOARD
When the board is ready for evaluation, apply positive input voltage to the VIN terminal
and the corresponding return to the ground terminal. The maximum input voltage
should not exceed 30V. An electronic load or resistive load can be used for evaluation.
The electronic loads attempt to sink current at 0V during startup. A resistive load or constant resistance is recommended for startup evaluation. Connect the positive voltage
terminal of the load to the VOUT terminal on the evaluation board, and connect the negative or return side of the load to the ground terminal.
Connectors are placed on the bottom side of board:
• VIN for positive power
• Two grounds for negative power
• VOUT connector for output load
DS50002063B-page 14
2012-2013 Microchip Technology Inc.
Installation and Operation
2.2.2
Board Testing
To test the board, follow these steps:
1. Apply the input voltage.
2. An external pull up resistor is connected from VIN to the EN input of the
MCP16301. Once the input voltage is greater than 3.5V, the device begins to
switch. Apply greater than 6V supply to the input for proper operation. A minimum
load is required to regulate the output to 5V. For minimum load requirements
(light load conditions), see the device data sheet for detailed information.
3. The measured output voltage should be 5V typical. Adjusting the input voltage
and load should not cause the output to vary more than a few mV over the operating range of the converter.
4. Typical conditions for evaluating the board are: 12V input, 100 mA load. Using
an oscilloscope, measure the AC ripple of the output without any bandwidth limitation. VOUT ripple plus noise should be approximately 30 mV. To avoid errors,
remove the ground lead of the scope probe and measure the output ripple on the
output capacitors pads. Use a short wire wrapped around the ground barrel of
the probe to touch the capacitor’s ground pad.
Note:
The VOUT ripple plus noise value varies with the input and output
parameters.
Additional analysis can be performed by changing the RC snubber and RBOOST resistor
values (see Figure 2-1). These additional circuits lower the efficiency, but reduce
switching noise.
Set 12V
Power Supply
FIGURE 2-2:
Circuit.
V-Meter
R
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board Setup
2012-2013 Microchip Technology Inc.
DS50002063B-page 15
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
2.2.3
How Does the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board Work?
The MCP16301 integrates a low resistance N-Channel MOSFET (typically 460 m). A
high-side or floating supply is needed to drive the gate of the N-Channel MOSFET
above the input voltage (to turn it on). The evaluation board uses the 5V output voltage
to charge the boost capacitor (CBOOST), while the inductor current flows, clamping the
SW node to a diode drop below ground. Prior to start up, there is no inductor current,
so an internal precharge circuit charges the boost cap up to a minimum threshold.
Once CBOOST is charged, the N-Channel MOSFET can be turned on, ramping current
into the inductor. The BOOST diode is used to provide a charging path for the CBOOST
capacitor, while current is flowing through the inductor.
The two sense resistors (RT and RB in Figure 2-1) set the output (VOUT) at 5.0V according to the following equation:
EQUATION 2-1:
V OUT
R TOP = R BOT ------------- – 1
V FB
where VFB = 0.8V is the reference voltage of the FB pin. The transconductance error
amplifier gain is controlled by its internal impedance. The external divider resistors
have no effect on system gain, so a wide range of values can be used. A 10 k resistor
is recommended as a good trade-off for quiescent current and noise immunity.
The MCP16301 device features integrated slope compensation to prevent the bimodal
operation of the pulse-width modulation (PWM) duty cycle. Internally, approximately
half of the inductor current down slope is summed with the internal current sense
signal. For the proper amount of slope compensation, it is recommended to keep the
inductor down-slope current constant by varying the inductance with VOUT. For 5.0V
output, a 22 µH inductor is recommended.
The input capacitor must filter the high input ripple current, as a result of pulsing or
chopping the input voltage. The MCP16301 input voltage pin is used to supply voltage
for the power train and as a source for internal bias. A low Equivalent Series Resistance
(ESR), preferably a ceramic capacitor, is recommended. The necessary capacitance is
dependent upon the maximum load current and source impedance. Minimum
capacitance at light load is 2.2 µF.
The output capacitor helps in providing a stable output voltage during sudden load
transients, and reduces the output voltage ripple. The minimum value of the output
capacitance is limited to 20 µF, due to the integrated compensation of the MCP16301.
The freewheeling diode creates a path for inductor current flow after the internal switch
is turned off. The efficiency of the converter is a function of the forward drop voltage
value and speed of the freewheeling Schottky diode.
For detailed information, see the MCP16301 Data Sheet (DS25004).
DS50002063B-page 16
2012-2013 Microchip Technology Inc.
Installation and Operation
2.2.4
Reduction of the High Frequency Switching Noise
Because the MCP16301’s internal MOSFET is switching at 500 kHz, high-frequency
noise may appear. This can affect the circuitry in close proximity. Parasitic elements
generate ringing. There are two main noise sources. The first source occurs at the
fundamental switching frequency and is called “Output Ripple”. The second source,
associated with high-frequency ringing, occurs during the ON-OFF transition of the
integrated N-Channel MOSFET switch. This results in a high-frequency noise that can
be in the range of 100s of MHz and up to 500 mV peak-to-peak voltage ripple. Both
noise components require separate filtering. Figure 2-3 shows an example of the two
noise components.
FIGURE 2-3:
VOUT Ripple and Noise for an MCP16301 Buck Converter
Without Any Noise Reduction Components.
The low-frequency output ripple of the MCP16301 is generally less than 20 mV
peak-to-peak, and it depends on the output capacitor value and capacitor dielectric
type. Low ESR and Equivalent Series Inductance (ESL) ceramic capacitors significantly decrease the output voltage low-frequency ripple.
Additional output capacitance does not remove the high-frequency noise. Ceramic
capacitors have high-impedance in the frequency band in which this noise occurs. The
ringing frequency is very high, and the output capacitor alone or an extra low-value
capacitor in parallel with it are ineffective in attenuating this noise. First, the noise can
be attenuated by good PCB design practices. A four-layer board is recommended in
this case. The solution is to place the SW node of the MCP16301 pin into the inner layer
(Mid-Layer 2) as an individual plane between two ground planes (Mid-Layer 1 and
Layer 4 - Bottom plane).
High-quality shielded inductors reduce the spreading of electromagnetic fields, a
desirable characteristic of any power supply. An example of a high-quality shielded
inductor is the CoilCraft Inc. XAL6060.
2012-2013 Microchip Technology Inc.
DS50002063B-page 17
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
The third and most effective method to reduce switching noise is to slow down the
turn-on of the integrated N-Channel MOSFET switch, addressing the noise at its
source. This method lowers the efficiency of the converter insignificantly
(see Figure 2-6), but the noise in the system is significantly reduced. A RBOOST
resistance value between 47 and 100 Ohms was typical for this analysis.
Placing an RC snubber in parallel with the external Schottky diode is another method
that can be used to reduce high-frequency noise. Some basic equations are used to
calculate the RC snubber values.
For example, the Schottky rectifier diode MBRA140T (1A/40V) has a parasitic
Lp = 2 nH and Cp = 38 pF (see the MBRA140T data sheet for details). When measuring
the MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board circuit without an RC snubber (for 12V Input and 100 mA load), the ringing frequency is
approximately 250 MHz. Considering the parasitic inductance equal to LP, calculate the
parasitic impedance, using the following equation:
EQUATION 2-2:
Z = 2 fL p
For this example, Z is approximately 3. Choose a snubber resistor to be similar or
greater than this value (4.7 standard value).
EQUATION 2-3:
R Snubber Z
Where:
RSnubber = 4.7
With the value of RSnubber established, the snubber’s capacitor value results from the
following equation:
EQUATION 2-4:
1
C Snubber = ----------------------------2 fR Snubber
Where:
CSnubber = 120 pF
DS50002063B-page 18
2012-2013 Microchip Technology Inc.
Installation and Operation
Figures 2-4 – 2-6 show the results for the MCP16301 High-Performance Low-Noise 5V
Buck Converter Evaluation Board:
• AC output ripple for board with RC snubber only (Figure 2-4)
• AC output ripple for RC snubber and RBOOST on board (Figure 2-5)
• Efficiency comparison with RC snubber and RBOOST (Figure 2-6)
FIGURE 2-4:
VOUT Ripple of the Evaluation Board is less than 80 mVp-p using
RC Snubber only (12V Input, 100 mA Load). Compare to Figure 2-3.
FIGURE 2-5:
VOUT Ripple of the Evaluation Board is less than 30 mVp-p using
RC Snubber and RBOOST (12V Input, 100 mA Load). Compare to Figures 2-3 and 2-4.
2012-2013 Microchip Technology Inc.
DS50002063B-page 19
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
Efficiency (%)
90
80
70
Vin = 12V, no RC Snubber, no RBoost
Vin = 24V no RC Snubber, no RBoost
60
Vin = 12V, RC Snubber, no RBoost
Vin = 24V, RC Snubber, no RBoost
50
Vin = 12V, Snubber, RBoost
Vin = 24V, Snubber, RBoost
40
0
100
200
300
IOUT (mA)
400
500
600
FIGURE 2-6:
Efficiency Comparison for the MCP16301 High-Performance
Low-Noise 5V Buck Converter Evaluation Board (12V and 24V Input).
DS50002063B-page 20
2012-2013 Microchip Technology Inc.
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
Appendix A. Schematic and Layouts
A.1
INTRODUCTION
This appendix contains the following schematics and layouts for the MCP16301
High-Performance Low-Noise 5V Buck Converter Evaluation Board:
•
•
•
•
•
Board – Schematic
Board – Top Silk And Copper
Board – Mid-Inner Layer 1
Board – Mid-Inner Layer 2
Board – Bottom Copper and Pads
2012-2013 Microchip Technology Inc.
DS50002063B-page 21
BOARD – SCHEMATIC
D1
VIN = 12V
J1
1N4148WS
1
R5
C2
10uF
C3
10uF
R1
1M
5
EN
SW
VFB
2
4
VIN
GND BOOST
1
VIN
MCP16301
U1
C1
0603
0.1uF
VOUT = 5V
J2
L1
6
22uH/5A
1
1%
R2
52.3K
3
R3
4.7
C7
J3
C6
VOUT
C4
10uF
C5
10uF
1%
0603
D2
MBRA140T3G
0603
1%
R4
10k
J4
120p
1
GND
82
2012-2013 Microchip Technology Inc.
GND
GND
GND
GND
1
GND
GND
GND
GND
GND
GND
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
DS50002063B-page 22
A.2
Schematic and Layouts
A.3
BOARD – TOP SILK AND COPPER
2012-2013 Microchip Technology Inc.
DS50002063B-page 23
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
A.4
BOARD – MID-INNER LAYER 1
DS50002063B-page 24
2012-2013 Microchip Technology Inc.
Schematic and Layouts
A.5
BOARD – MID-INNER LAYER 2
2012-2013 Microchip Technology Inc.
DS50002063B-page 25
MCP16301 High-Performance Low-Noise 5V Buck Converter Evaluation Board User’s Guide
A.6
BOARD – BOTTOM COPPER AND PADS
DS50002063B-page 26
2012-2013 Microchip Technology Inc.
MCP16301 HIGH-PERFORMANCE
LOW-NOISE 5V BUCK CONVERTER
EVALUATION BOARD USER’S GUIDE
Appendix B. Bill of Materials (BOM)
TABLE B-1:
Qty.
BILL OF MATERIALS (BOM)
Reference
Description
Manufacturer
1
C1
Cap. ceramic 0.1 µF 50V X7R 10% 0603
TDK®
2
C2, C3
Cap. ceramic 10 µF 50V X7S 1210
TDK Corporation
Part Number
Corporation
C1608X7R1H104K
C3225X7S1H106M
®
2
C4, C5
Cap. ceramic 10 µF 10V X7R 10% 0805
Murata Electronics
GRM21BR71A106KE51L
0
C6
DO NOT POPULATE
—
—
1
C7
Capacitor, NP0, 0603, 100V, 120 pF
KEMET®
1
D1
Diode switch 75V 200 mW SOD323
Diodes® Incorporated 1N4148WS-7-F
1
D2
Diode Schottky 40V 1A SMA
ON Semiconductor®
MBRA140T3G
4
J1, J2, J3, J4 PC test point tin SMD
Harwin Plc.
S1751-46R
1
L1
Inductor 22 µH 5A SMD
Coilcraft®
XAL6060-223MEB
1
PCB
Printed Circuit Board - MCP16301
High-Performance Low-Noise 5V Buck
Converter Evaluation Board
—
104-00433
1
R1
Res. 1.0M Ohm 1/10W 5% 0603 SMD
Panasonic® - ECG
ERJ-3GEYJ105V
1
R2
Res. 52.3k Ohm 1/10W .1% 0603 SMD
Panasonic - ECG
ERA-3AEB5232V
1
R4
Res. 10k Ohm 1/10W 1% 0603 SMD
Panasonic - ECG
ERJ-3EKF1002V
1
R5
Res. 82 Ohm 1/10W 5% 0603 SMD
Panasonic - ECG
ERJ-3GEYJ820V
1
R3
Res. 4.7 Ohm 1/10W 1% 0603 SMD
Panasonic - ECG
ERJ-3RQF4R7V
1
U1
High-Voltage Input Integrated Switch
Step-Down Regulator
Microchip
Technology Inc.
MCP16301T-E/CH
Note 1:
Corp.
C0603C121J1GACTU
The components listed in this Bill of Materials are representative of the PCB assembly. The
released BOM used in manufacturing uses all RoHS-compliant components.
2012-2013 Microchip Technology Inc.
DS50002063B-page 27
Worldwide Sales and Service
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DS50002063B-page 28
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11/29/12
2012-2013 Microchip Technology Inc.