MAXIM MAX15049EVKIT+

19-5149; Rev 0; 1/10
MAX15049 Evaluation Kit
The MAX15049 evaluation kit (EV kit) is a fully assembled
and tested PCB that demonstrates the capabilities of
the MAX15049. The MAX15049 is a high-performance,
triple-output synchronous buck controller with sequencing capability. The EV kit requires a 5V to 16V (12V, typ)
DC input-voltage range for normal operation.
The MAX15049 EV kit outputs are configured for 3.3V,
1.8V, and 1.2V. They provide a load current of 3A, 3A,
and 6A, respectively. The EV kit’s switching frequency
is set to 500kHz, but can be programmed up to 1.2MHz
by replacing a resistor. The EV kit comes configured
for sequencing (MAX15049) and is capable of prebias
startup. The EV kit can also be used to evaluate the
MAX15048 for tracking applications by changing a few
components. The PGOOD logic signal output pad is
provided for circuit monitoring.
The MAX15049 EV kit comes with a MAX15049ETJ+
installed. To evaluate the MAX15048, contact the factory
for samples of the pin-compatible MAX15048ETJ+.
Features
S Triple-Output Power Supply
VOUT1 (3.3V, 3A)
VOUT2 (1.8V, 3A)
VOUT3 (1.2V, 6A)
S 5.5V to 16V Input-Voltage Operation (Design
Optimized for 12V Input)
S Optional 4.5V to 5.5V Input-Voltage Operation
S 500kHz Switching Frequency per Converter
S Programmable Switching Frequency Up to 1.2MHz
S Sequencing Operation (Tracking Possible with
Component Changes)
S PGOOD Power Monitoring
S Small 1.5in x 1in Circuit Footprint
S 92.8% Peak Efficiency for OUT1
S Fully Assembled and Tested
Ordering Information
PART
TYPE
MAX15049EVKIT+
EV Kit
+Denotes lead(Pb)-free and RoHS compliant.
Component List
DESIGNATION
QTY
C1, C8, C9,
C18, C19, C38
6
C2
C5, C7, C15,
C17, C25, C26,
C35
C6, C16
C10, C20
C11, C22
DESCRIPTION
DESIGNATION
QTY
DESCRIPTION
22FF Q20%, 16V X5R ceramic
capacitors (1206)
Murata GRM31CR61C226M
C12, C23, C30
3
22pF Q5%, 50V C0G ceramic
capacitors (0402)
Murata GRM1555C1H220J
1
1FF Q10%, 16V X5R ceramic
capacitor (0603)
Murata GRM188R61C105K
C13, C21, C32
3
1500pF Q10%, 50V X7R
ceramic capacitors (0402)
Murata GRM155R71H152K
7
0.1FF Q10%, 16V X5R ceramic
capacitors (0402)
Murata GRM155R61A104K
C14, C24
0
Not installed, ceramic
capacitors (0402)
C27, C28
2
2
10FF Q10%, 16V X5R ceramic
capacitors (0805)
Murata GRM21BR61C106K
100FF Q20%, 6.3V X5R ceramic
capacitors (1210)
Murata GRM32ER60J107M
C29
1
2
0.1FF Q10%, 16V X7R ceramic
capacitors (0603)
Murata GRM188R71C104K
220pF Q10%, 10V X7R ceramic
capacitor (0402)
Murata GRM155R61A103K
C31
1
2
330pF Q5% 50V C0G ceramic
capacitors (0402)
Murata GRM1555C1H331J
680pF Q10%, 50V X7R ceramic
capacitor (0402)
Murata GRM155R71H681K
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Evaluates: MAX15048/MAX15049
General Description
Evaluates: MAX15048/MAX15049
MAX15049 Evaluation Kit
Component List (continued)
DESIGNATION
QTY
C33
C34
C36, C37, C39
DESCRIPTION
1
1FF Q10%, 6.3V X5R ceramic
capacitor (0402)
Murata GRM155R60J105K
1
2.2FF Q20%, 6.3V X5R ceramic
capacitor (0402)
Murata GRM155R60J225M
3
DESIGNATION
QTY
R1, R7, R13
3
0I Q5% resistors (0402)
R2, R8, R19
0
Not installed, resistors (0402)
R3, R9, R16,
R18
4
24.9kI Q1% resistors (0402)
R4, R10, R17
3
15kI Q1% resistors (0402)
R5, R11
2
1kI Q1% resistors (0402)
R6
1
5.49kI Q1% resistor (0402)
R12
1
12.4kI Q1% resistor (0402)
R14
1
20I Q5% resistor (0402)
R15
1
499I Q1% resistor (0402)
R20
1
2.2I Q5% resistor (0402)
R21
1
39.2kI Q1% resistor (0402)
R22
1
20kI Q5% resistor (0402)
R23, R24, R28
3
10kI Q1% resistors (0402)
R25
1
4.99kI Q1% resistor (0402)
1000pF Q10%, 50V X7R
ceramic capacitors (0402)
Murata GRM155R71H102K
DESCRIPTION
EN1, EN2, EN3,
PGOOD, REG,
SGND
6
1-pin headers
JU1
0
Not installed, 2-pin header
L1, L2
2
3.3FH, 7A, 26mI inductors
Vishay IHLP2525CZER3R3M07
L3
1
1FH, 14.1A, 7.1mI inductor
TDK SPM6530T-1R0M120
R26
1
2.49kI Q1% resistor (0402)
R27
1
59kI Q1% resistor (0402)
30V dual n-channel
PowerTrench MOSFETs (MLP)
Fairchild FDMC8200
R29
0
Not installed, resistor (0603)
U1
1
Triple-output buck controller
(32 TQFN–EP*)
Maxim MAX15049ETJ+
—
1
PCB: MAX15049 EVALUATION
KIT+
N1, N2
2
N3
1
9.1A/11A, 30V dual n-channel
MOSFET (SO8)
International Rectifier
IRF7907PbF
*EP = Exposed pad.
Component Suppliers
SUPPLIER
PHONE
WEBSITE
Fairchild Semiconductor
888-522-5372
www.fairchildsemi.com
International Rectifier
310-322-3331
www.irf.com
Murata Electronics North America, Inc.
770-436-1300
www.murata-northamerica.com
TDK Corp.
847-803-6100
www.component.tdk.com
Vishay
402-563-6866
www.vishay.com
Note: Indicate that you are using the MAX15049 when contacting these component suppliers.
2 _______________________________________________________________________________________
MAX15049 Evaluation Kit
MAX15049 EV kit
•
12V, 10A power supply
•
Four voltmeters
Detailed Description of Hardware
Required Equipment
The MAX15049 EV kit is a fully assembled and tested
PCB that demonstrates the MAX15049, which integrates three high-performance PWM switching stepdown DC-DC controllers. The EV kit circuit operates over
the input-voltage range of 4.7V to 16V. The three outputs
are configured for 3.3V, 1.8V, and 1.2V and can provide
3A, 3A, and 6A, respectively. The EV kit outputs operate
in sequencing mode during startup and the three outputs
operate 120 degrees out of phase. The EV kit outputs
can start into prebiased loads. The EV kit switching frequency is set to 500kHz with resistor R21. The switching
frequency can be programmed from 200kHz to 1.2MHz
by replacing this resistor. The EV kit has a PGOOD output pad to indicate that all outputs have reached their
steady-state values. The EV kit PCB is designed in four
layers and 2oz copper for optimum performance.
Procedure
The MAX15049 EV kit is fully assembled and
tested. Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all
connections are completed.
1) Verify that U1 is installed on the bottom side of the
PCB.
2) Connect the positive terminal of voltmeter 1 (VM1)
to the OUT1 pad. Connect the negative terminal of
VM1 to the GND1 pad.
3) Connect the positive terminal of voltmeter 2 (VM2)
to the OUT2 pad. Connect the negative terminal of
VM2 to the GND2 pad.
4) Connect the positive terminal of voltmeter 3 (VM3)
to the OUT3 pad. Connect the negative terminal of
VM3 to the GND3 pad.
5) Connect the positive terminal of voltmeter 4 (VM4)
to PGOOD (TP8) and the negative terminal to the
PGND pad.
Input Source
The MAX15049 EV kit is configured for normal operation
with an input power source of 4.7V to 16V and design
optimized for a 12V input voltage. The upper inputvoltage limit can be raised to 23V by replacing capacitors C1, C2, C6, C16, and C38 with higher voltage-rated
capacitors. The EV kit circuit requires a minimum 4.7V
input voltage to start the power MOSFET switching.
MAX15049 Bias Input
8) Turn on the power supply.
The MAX15049 EV kit features an option to select the
bias input for the MAX15049 when configuring the EV kit
to operate with an input source less than 4.7V. Jumper
JU1 shorts the input-voltage source for the MAX15049 to
the controller REG pin. Without JU1 installed, the inputvoltage range in this configuration is 4.7V to 16V.
9) Verify that the VOUT1, VOUT2, and VOUT3 outputs
measure 3.3V, 1.8V, and 1.2V, respectively.
When operating the MAX15049 EV kit with a supply
between 4.5V to 5.5V, install jumper JU1.
6) Set the power supply to 12V and disable the output.
7) Connect the positive terminal of the power supply
to the VIN pad. Connect the negative terminal of the
power supply to the PGND pad.
10) Verify that PGOOD measures approximately 5V.
11) The EV kit is now ready for load testing. Use the
respective OUT_ connector load points for highcurrent load testing.
Table 1. MAX15049 Bias Input Configuration (JU1)
SHUNT POSITION
MAX15049 IN PIN
MAX15049 EV KIT INPUT RANGE (V)
Installed
Connected to REG
4.5 to 5.5
Not installed
Connected to VIN
4.7 to 16
_______________________________________________________________________________________ 3
Evaluates: MAX15048/MAX15049
•
Quick Start
Evaluates: MAX15048/MAX15049
MAX15049 Evaluation Kit
Triple Outputs
The MAX15049 EV kit’s three outputs are configured to
different voltages. The bottom side of the PCB contains
the IC and the feedback and compensation components. The top side of the PCB contains the input/output
capacitors, inductors, and FETs. OUT1 is configured to
3.3V with resistors R3 and R6 and can supply up to 3A.
OUT2 is configured to 1.8V with resistors R9 and R12
and can supply up to 3A. OUT3 is configured to 1.2V
with resistors R16 and R18 and can supply up to 6A.
The output voltage for each output can be reconfigured
between 0.6V and 3.3V by replacing the respective feedback resistors. Refer to the Type III: Compensation When
ƒCO < ƒZERO, ESR section in the MAX15048/MAX15049
IC data sheet for instructions on selecting new resistor values for the respective outputs. Also, refer to the
Inductor Selection and Input-Capacitor Selection sections in the IC data sheet to verify other component
replacements for proper operation when changing the
output voltage.
Current Limit
The MAX15049 EV kit uses the low-side MOSFET DC
on resistance (RDSON) for valley current sensing. The
current-limit threshold is 69mV internally set inside
the MAX15049. The MAX15049 compares the voltage
across the low-side MOSFET (RDSON) with the internal
threshold to incorporate the current limit. OUT1 and
OUT2 use the FDMC8200 FET with a low-side RDSON of
9.5mI (typ) and 13.5mI (max). The current-limit threshold is 69mV (typ) and the output current limit calculated
is approximately 6A. The IRF7907 FET has similar characteristics with a 9.1mI (typ) and 13.7mI (max) RDSON
and therefore, a similar current limit.
Switching Frequency
The MAX15049 PWM switching frequency is set to approximately 500kHz with resistor R21 (39.2kI). Replace
resistor R21 with a new resistor value to progam the
switching frequency between 200kHz and 1.2MHz. Use
the following equation to choose the appropriate resistor
value to reconfigure the switching frequency (fSW):
fSW (kHz) = 12.8 × R21 (kΩ)
Evaluating the MAX15048 (Tracking)
The MAX15049 EV kit comes configured for sequencing.
The EV kit can also evaluate the MAX15048 for tracking
applications. The MAX15049 IC must be replaced with
the MAX15048. It also requires modification at EN2
(pin 9) and EN3 (pin 24) for tracking operation with
the MAX15048. Refer to the MAX15048 Coincident/
Ratiometric Tracking (EN_) section in the MAX15048/
MAX15049 IC data sheet to calculate the proper values
for resistors R23–R26 and R29.
PGOOD Status Output
The MAX15049 EV kit provides a PGOOD logic output to
indicate the regulation state of OUT1, OUT2, and OUT3.
A logic-low at TP8 (PGOOD test point) indicates that one
of the output voltages has dropped below 92% of its
regulation voltage.
Individual EN_ Input
The MAX15049 EV kit provides an individual enable test
point for each output. The EV kit comes configured for
sequencing and connections so the enable test points
are not needed. To disable sequencing and externally
control each output, remove the sequencing components (R23–R28) and apply a voltage on the EN_ test
point.
4 _______________________________________________________________________________________
MAX15049 Evaluation Kit
Evaluates: MAX15048/MAX15049
Figure 1. MAX15049 EV Kit Schematic
_______________________________________________________________________________________ 5
Evaluates: MAX15048/MAX15049
MAX15049 Evaluation Kit
1.0”
Figure 2. MAX15049 EV Kit Component Placement Guide—
Component Side
1.0”
Figure 3. MAX15049 EV Kit PCB Layout—Component Side
1.0”
Figure 4. MAX15049 EV Kit PCB Layout—Layer 2 (Ground
Layer)
6 _______________________________________________________________________________________
MAX15049 Evaluation Kit
Figure 5. MAX15049 EV Kit PCB Layout—Layer 3
(Power Layer)
Evaluates: MAX15048/MAX15049
1.0”
1.0”
Figure 6. MAX15049 EV Kit PCB Layout—Solder Side
1.0”
Figure 7. MAX15049 EV Kit Component Placement Guide—
Solder Side
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time.
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© 2010
Maxim Integrated Products 7
Maxim is a registered trademark of Maxim Integrated Products, Inc.