MIC4930YFL Evaluation Board User Guide

MIC4930 Evaluation Board
HyperSpeed™ 5A Buck Regulator in
3mm x 4mm DFN Package
General Description
This board enables the evaluation of the MIC4930, a fully
integrated 5A switching regulator featuring HyperSpeed™
control and Power Good output indication. The MIC4930 is
highly efficient throughout the entire output current range,
exceeding 95% over 5V input to 3.3V output range. The
tiny 3mm x 4mm DFN package, in combination with the
high switching frequency, allows for a compact, small
footprint solution. The MIC4930 provides accurate output
voltage regulation under the most demanding conditions
and responds extremely fast to a load transient with
exceptionally small output voltage ripple.
Data sheets and other support documents can be found on
Micrel’s web site at: www.micrel.com.
Requirements
The MIC4930 evaluation board requires a single power
source adjustable up to at least 5.5V, with 5A of current
capability. The load can either be active (electronic load)
or passive (resistor) with the capability to dissipate 20W. It
is ideal to have an oscilloscope available to view the circuit
waveforms, but not essential. For the simplest tests, two
voltage meters are required to measure input and output
voltage. For efficiency measurements, two voltage meters
and two ammeters are required to prevent errors due to
measurement inaccuracies.
Precautions
There is no reverse input protection on this board. Be
certain that the correct polarity is observed when
connecting the input source.
The maximum VIN of the board is rated at 5.5V, and the
maximum load current is rated at 5A.
Input power leads should ensure negligible voltage drop
up to the maximum load, and should be kept as short as
possible to minimize inductance.
For load transient and/or pre-biased output start-up testing
up to 5.5V VIN, the use of a bulk electrolytic capacitor in
position C7 (at least 100µF, 10V rating) is recommended.
Getting Started
1. Connect an external supply to the VIN (J1) terminal
and GND (J2).
With the output of the power supply disabled, set its
voltage to the desired input test voltage (2.7V ≤ VIN ≤
5.5V). An ammeter may be placed between the input
supply and the VIN (TP4) terminal. Be sure to monitor
the supply voltage at the VIN (TP4) terminal, as the
ammeter and/or power lead resistance can reduce the
voltage supplied to the device.
2. Connect a load to the VOUT (J3) and ground (J4)
terminals.
The load can be either active passive (resistive) or
active (electronic load). In case of electronic load,
keep the load disabled until the MIC4930 has been
powered up.
An ammeter may be placed between the load and the
output terminal. Ensure the output voltage is monitored
at the VOUT (TP6) terminal.
3. Enable the MIC4930.
The MIC4930 evaluation board has a pull-up resistor
R6 to VIN. With a jumper installed in positions 1-2 of
TP5, the output voltage will be enabled when the input
supply of >2.7V is applied. To disable the device,
apply a voltage below 0.5V to the EN (TP2) terminal,
or install a jumper across positions 2-3 of TP5.
4. Power Good.
A Power good test point (TP3) is provided to monitor
the Power Good function. The Power Good output will
go high (approximately 80µs) after the output voltage
reaches 88% of its nominal voltage.
Ordering Information
Part Number
MIC4930YFL EV
Description
1.8V Fixed Output Evaluation Board
HyperSpeed is a 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
April 15, 2014
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Micrel, Inc.
MIC4930 Evaluation Board
Evaluation Board
Other Features
Feedback Resistors (R1, R2) for Adjustable Output
The output voltage is set nominally to 1.8V. This output
can be changed by adjusting the upper resistor, R1, in the
feedback potential divider. Therefore:
R2 = R1 x VREF/(VOUT-VREF)
Where VREF = 0.625V
Some example values are:
VOUT
R1
R2
1.0V
120k
180k
1.2V
274k
294k
1.5V
316k
226k
1.8V
301k
160k
2.5V
316k
105k
3.3V
309k
71.5k
The feed-forward capacitor, C3, is typically in the range
22pF-39pF. The MIC4930 features an internal ripple
injection network, whose current is injected into the FB
node and integrated by C3, thus the waveform at FB is
approximately a triangular ripple. The size of C3 dictates
the amount of ripple amplitude at the FB node. Smaller
values of C3 yield higher FB ripple amplitude and better
stability, but also degrade somewhat line regulation and
transient response.
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MIC4930 Evaluation Board
MIC4930 Evaluation Board Schematic
Bill of Materials
Item
Part Number
Manufacturer
C2012X5R1A106M125AB
TDK
GRM219R61A106ME44
Murata(2)
C1608C0G1H220J080AA
TDK
GRM1885C1H220JA01
Murata
C1608X5R1A105M080AC
TDK
GRM185R61A105ME26
Murata
C5
-
C6
C7
C1,
C2
C3
C4
L1
Description
Qty.
(1)
Ceramic Capacitor, 10µF, 10V, X5R, Size 0805
2
Ceramic Capacitor, 22pF, 50V, C0G, Size 0603
1
Ceramic Capacitor, 1µF, 10V, X5R, Size 0603
1
-
Not Fitted (FT), Size 0603
0
-
-
Not Fitted (FT), Size 1210
0
-
-
Not Fitted (FT), Radial, 8mm diameter polarized capacitor
0
RLF7030T-1R0N6R4
TDK
1µH, 6.4A, 7.3mΩ, L7.3mm x W6.8mm x H3.2mm
CLF7045T-1R0N
TDK
CDRH8D43RT125NP-1R0NC
1µH, 5.2A, 9.6mΩ, L7.2mm x W6.9mm x H4.5mm
1
1µH, 7.5A, 7.8mΩ, L8.5mm x W8.3mm x H4.5 mm
(3)
Sumida
R1
CRCW06033013FK
Vishay
Resistor, 301kΩ, Size 0603
1
R2
CRCW06031603F
Vishay
Resistor, 160kΩ, Size 0603
1
R3
-
-
Not Fitted (FT), Size 0603
0
R4
CRCW060310R0FK
Vishay
Resistor, 10Ω, Size 0603
1
R5
CRCW06031002FK
Vishay
Resistor, 10kΩ, Size 0603
1
R6
CRCW06031003FK
Vishay
Resistor, 100kΩ, Size 0603
1
R7
CRCW060349R9FK
Vishay
Resistor, 49.9Ω, Size 0603
1
HyperSpeed™ 5A Buck Regulator
1
U1
MIC4930YFL
(4)
Micrel, Inc.
(5)
Notes:
1.
TDK: www.tdk.com.
2.
Murata: www.murata.com.
3. Sumida: www.sumida.com
4.
Vishay: www.vishay.com.
5. Micrel, Inc.: www.micrel.com.
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MIC4930 Evaluation Board
PCB Layout Recommendations
Top Layer
Bottom Layer
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MIC4930 Evaluation Board
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.
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MIC4930 Evaluation Board
Revision History
Date
Change Description/Edits by:
1/12/10
Changed dates in template. M. Galvan
0.5
8/4/10
Added new paragraph to disclaimer in boiler plate. Per Colin Sturt. M.Galvan
1.0
1/7/13
Complete rework
2.0
4/30/13
Made notes run continuously, rather than restart on each page
2.1
12/17/13
Original release by Paolo Nora
0.0
April 15, 2014
Rev.
6
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