Linear Technology DC1472A Quick setup guide

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dc1472af
DEMO MANUAL DC1472A
DESCRIPTION
LTM4618EV:
6A Step-Down Power
µModule Regulator
Demonstration circuit 1472 features the LTM
®
4618EV
μModule
®
regulator, a complete high efficiency synchro-
nous buck regulator. The DC1472 input range is from 4.5V
to 26.5V and is capable of delivering up to 6A of output
current. However, current derating maybe necessary under
certain VIN, VOUT, frequency and thermal conditions. The
output voltage for the board is jumper programmable from
1.2V to 5V and can be set as low as 0.8V, the reference
voltage of the LTM4618EV.
Layout is simple, requiring only a few bulk input and output
capacitors externally. The TRACK/SS pin allows the user to
program the output voltage ramp-up and ramp-down, as
well as coincidentally or ratiometrically track an external
voltage. The LTM4618EV may be enabled or disabled by
the RUN pin. The MODE jumper (JP3) is available to select
L, LT, LTC, LTM, μModule, Burst Mode, Linear Technology and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
BOARD PHOTO
frompulse-skipping orBurst Mode
®
operationfor improved
efficiency at light load. DC1472 has a default switching
frequency of 500 kHz and is synchronizable to an external
clock from 250 kHz up to 750 kHz. These features and the
availability of the LTM4618EV in a compact 9mm ×15mm
×4.32mm LGA package make the demonstration circuit
ideal for use in many high density point-of-load regula-
tion applications. The LTM4618 data sheet must be read
in conjunction with this demo manual for working on or
modifying the demo circuit 1472A.
Design files for this circuit board are available at
http://www.linear.com/demo
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DEMO MANUAL DC1472A
QUICK START PROCEDURE
PERFORMANCE SUMMARY
PARAMETER CONDITIONS/NOTES VALUE
Input Voltage Range 4.5V to 26.5V
Jumper Selectable Output Voltage, VOUT VIN = 4.5V – 26.5V, IOUT = 0A – 6A 1.2V, 1.5V, 1.8V, 2.5V, 3.3V or 5V ±2%
Maximum Continuous Output Current Derating is Necessary for Certain Operating Conditions.
See Data Sheet for Details
6ADC
Default Operating Frequency R3 = 10kΩ, R4 = 3.16kΩ 500kHz
External Clock Sync. Frequency Range 250kHz to 750kHz
Efficiency VIN = 12V, VOUT = 2.5V, IOUT = 6A 88.7% See Figure 2
Demonstration circuit 1472 is easy to set up to evaluate the
performance of the LTM4618EV. Please refer to Figure1
for proper measurement equipment setup and follow the
procedure below.
1. With power off, connect the input power supply, load
and meters as shown in Figure 1. Preset the load to 0A
and VIN supply to be 0V. Place jumpers in the following
positions for a typical 1.5VOUT application:
JP6 JP3 JP4 JP2
VOUT Select MODE RUN TRACK/SS
1.5V CCM OFF SS
2. Turn on the power at the input. Increase VIN to 12V
(Caution: Do not hot plug the input supply or apply
more than the rated maximum voltage of 26.5V to the
board or the part may be damaged).
3. Set the RUN pin jumper (JP4) to the on position. The
output voltage should rise to 1.5V. The output voltage
meter should read the selected output voltage ±2%.
4. Vary the input voltage from 6V to 24V and adjust the
load current from 0A to 6A. The output voltage meter
should read the selected output voltage ±2%. Set the
input voltage to 12V and the load current to 6A.
5. Measure the output voltage ripple at J5 with a BNC
cable and oscilloscope.
6. To set the output voltage to 5V, turn off the input supply
power, apply the following changes listed below and
repeat steps 2 to 5:
JP10 JP3 JP4 JP2
VOUT Select MODE RUN TRACK/SS
5V CCM OFF SS
7. Set the load current to 0A. Set the RUN pin jumper
(JP4) to the OFF position. Power off the input supply.
8. For loadtransient tests,apply an adjustablepositive pulse
signal between IOSTEP CLK and GND test points. The
pulse amplitude sets the load step current amplitude.
The pulse width should be short (<1ms) and pulse duty
cycle should be low (<15%) to limit the thermal stress
on the load transient circuit. The load step current can
be monitored with a BNC connected to J6 (10mV/A).
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DEMO MANUAL DC1472A
QUICK START PROCEDURE
Figure 1. Proper Measurement Equipment Setup
+
A
V
–
+
V
+
–
A
–+
+–
VIN
LOAD
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DEMO MANUAL DC1472A
Figure 2. Measured Supply Efficiency at 12VIN and 24VIN
Efficiency vs Load Current, 12VIN
Efficiency vs Load Current, 24VIN
QUICK START PROCEDURE
LOAD CURRENT (A)
0
EFFICIENCY (%)
80
85
DC1472 F02a
75
70 246
95
90
5VOUT
3.3VOUT
2.5VOUT
1.8VOUT
1.5VOUT
1.2VOUT
fSW = 500kHz
CCM Mode
LOAD CURRENT (A)
0
EFFICIENCY (%)
80
85
DC1472 F02b
75
70 246
95
90
5VOUT
3.3VOUT
2.5VOUT
1.8VOUT
1.5VOUT
fSW = 500kHz
CCM Mode
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DEMO MANUAL DC1472A
VIN (V) VOUT (V) COUT BULK COUT CERAMIC
12 1.5 330μF/6.3V POSCAP 1 ×47μF 10V
VIN (V) VOUT (V) IOUT (A) AIRFLOW AMBIENT (°C)
12 1.5 6 Natural Convection 27
Figure 3. Measured Load Transient Response (0A to 6A Load Step)
Figure 4. Measured Thermal Capture
QUICK START PROCEDURE
VOUT
100mV/DIV
IOUTSTEP
5A/DIV
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DEMO MANUAL DC1472A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C5 CAP, 150μF 35V, ALUM SANYO, 35ME150WXV+TS
2 2 C6, C7 CAP, X5R, 10μF 35V, 1210 TAIYO YUDEN, GMK325BJ106MN-T
3 1 C12 CAP, X5R, 47μF 10V, 1210 TDK, C3225X5R1A476M
4 1 C14 CAP, POSCAP, 330μF 6.3V, 7343 SANYO, 6TPC330MA
5 1 C15 CAP, X5R, 1μF 10V, 0805 AVX, 0805ZD105MAT2A
6 1 C20 CAP, X7R, 0.1μF 16V, 0603 AVX, 0603YC104KAT2A
7 1 R1 RES., 121k 1/16W 1%, 0603 VISHAY, CRCW0603121KFKEA
8 4 R3, R11 RES., 10k 1/16W 1%, 0603 VISHAY, CRCW060310K0FKEA
9 1 R4 RES., 3.16k 1/16W 1%, 0603 VISHAY, CRCW06033K16FKEA
10 1 R5 RES., 60.4k 1/16W 1%, 0603 VISHAY, CRCW060360K4FKEA
11 1 R14 RES., 69.8k 1/16W 1%, 0603 VISHAY, CRCW060369K8FKEA
12 1 R16 RES., 48.7k 1/16W 1%, 0603 VISHAY, CRCW060348K7FKEA
13 1 R17 RES., 28.7k 1/16W 1%, 0603 VISHAY, CRCW060328K7FKEA
14 1 R18 RES., 19.1k 1/16W 1%, 0603 VISHAY, CRCW060319K1FKEA
15 1 R19 RES., 11.5k 1/16W 1%, 0603 VISHAY, CRCW060311K5FKEA
16 1 U1 IC, LTM4618EV LINEAR TECH., LTM4618EV LGA
Additional Demo Board Circuit Components
1 0 C1-C4, C16, C19, C21-C24 CAP, 0603 Optional
2 0 C8, C9, C10, C11, C13 CAP, 1210 Optional
3 2 C17, C18 CAP, X5R, 1μF 10V, 0603 TAIYO YUDEN, LMK107BJ105MA-T
4 0 R6, R8, R10, R12 RES, 0603 Optional
5 4 R7 RES., 10k 1/16W 1%, 0603 VISHAY, CRCW060310K0FKEA
6 1 R9 RES., 0.01Ω 5% 1W, 2512 IRC, LRC-LRF2512LF-01-R010-J
7 1 R15 RES., 10k 1/16W 1%, 0603 VISHAY, CRCW060310K0FKEA
8 1 R2 RES., 100k 1/16W 1%, 0603 VISHAY, CRCW0603100KFKEA
9 1 R13 RES., CHIP, 0, 1/16W, 0603 VISHAY, CRCW06030000Z0EA
10 1 D1 DIODE, ZENER 350MW 4.7V, SOT-23 DIODES INC., BZX84C4V7-7-F
11 1 Q1 XSTR, SUD50N03-10CP MOSFET SILICONIX, SUD50N03-10CP
Hardware
1 10 E1-E10 TP, TURRET, 0.094", PBF MILL-MAX, 2501-2-00-80-00-00-07-0
2 3 JP1, JP2, JP4 JMP, 1X3, 0.079" SAMTEC, TMM-103-02-L-S
3 1 JP3 JMP, 1X4, 0.079" SAMTEC, TMM-104-02-L-S
4 6 JP5, JP6, JP7, JP8, JP9, JP10 JMP, 1X2, 0.079" SAMTEC, TMM-102-02-L-S
5 4 J1, J2, J3, J4 JACK, BANANA KEYSTONE, 575-4
6 2 J5, J6 CONN, BNC, 5 PINS CONNEX, 112404
7 5 JP1-JP4, JP6 SHUNT, 0.079" CENTER SAMTEC, 2SN-BK-G
8 4 4 Corners STANDOFF, SNAP ON, 0.50" KEYSTONE, 8833
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DEMO MANUAL DC1472A
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However,no responsibility is assumed for its use. LinearTechnology Corporation makes no representation
that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SCHEMATIC DIAGRAM
5 5
4 4
3 3
2 2
1 1
D D C C B B A A
1. ALL RESISTORS ARE IN OHMS, 0603. ALL CAPACITORS ARE IN MICROFARADS, 0603. NOTE: UNLESS OTHERWISE SPECIFIED 2. INSTALL SHUNTS AS SHOWN. FSW = 500KHz
VOUT
VIN
5V
INTVCC
VIN
5V
5V
INTVCC
INTVCC
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Monday, March 15, 2010
11
HIGH DENSITY 6A STEP-DOWN POWER uMODULE
KT
SAM Y.
N/A
LTM4618EV
DEMO CIRCUIT 1472A
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Monday, March 15, 2010
11
HIGH DENSITY 6A STEP-DOWN POWER uMODULE
KT
SAM Y.
N/A
LTM4618EV
DEMO CIRCUIT 1472A
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Monday, March 15, 2010
11
HIGH DENSITY 6A STEP-DOWN POWER uMODULE
KT
SAM Y.
N/A
LTM4618EV
DEMO CIRCUIT 1472A
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
SAM Y.PRODUCTION2 03-15-10
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
SAM Y.PRODUCTION2 03-15-10
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
SAM Y.PRODUCTION2 03-15-10
J6
IOSTEP
J6
IOSTEP
R19 11.5k R19 11.5k
C6
10uF
35V 1210 C6
10uF
35V 1210
JP8
2.5V
JP8
2.5V
E2
EXTVCC
E2
EXTVCC
R18 19.1k R18 19.1k
C16
OPT
C16
OPT
R3 10k R3 10k
C13 OPT 1210 C13 OPT 1210
JP7
1.8V
JP7
1.8V
C17 1uF 10V C17 1uF 10V
TP1TP1 C19
OPT C19 OPT
R17 28.7k R17 28.7k
R11 10k R11 10k
C3
OPT
C3
OPT
C20 0.1uF C20 0.1uF
E7
TRACK
E7
TRACK
R9 0.01 2512 R9 0.01 2512
JP5
1.2V
JP5
1.2V
E1
PGOOD
E1
PGOOD
R16 48.7k R16 48.7k
JP4
RUN
OFF
ON
JP4
RUN
OFF
ON
1 3 2
J3 VOUT
6A MAX
J3 VOUT
6A MAX
C4
OPT
C4
OPT
E9
SGND
E9
SGND
J1
VIN
4.5V - 26.5V
J1
VIN
4.5V - 26.5V
C1 OPT C1 OPT
C12
47uF
10V 1210 C12
47uF
10V 1210
E3
VIN
E3
VIN
U1
LTM4618EV
U1
LTM4618EV
GND
A4
GND
F6
GND
F7
GND
F5 GND
F4 GND
F3 GND
F2 GND
F1
GND
G7 GND
G6
NC A1
INTVCC D3
GND
G5 GND
G4
GND
E4
VIN
A5
SW
K6
VIN
A6
VIN
A7
VOUT J1 VOUT J2
VIN
B5
VIN
B6
VIN
B7
VIN
C5
VIN
C6
VIN
C7
VOUT J3 VOUT J4
PLLFLTR A2
TRACK/SS
B1
VOUT K1 VOUT K2 VOUT K3
RUN
B2
VFB D1
GND
E3
PGOOD D2
GND
E2 GND E1
VOUT K4 VOUT L1 VOUT L2
GND
D7 GND D6 GND D5 GND D4 GND B4
GND
G3 GND
G2 GND
G1
VOUT L3 VOUT L4 VOUT M1 VOUT M2 VOUT M3 VOUT M4
GND
E5
GND
E6
GND
E7
GND
H1
GND
H2
GND
H3
GND
H4
GND
H5
GND
H6
GND
H7
GND J5 GND J6 GND J7 GND K5 GND K7 GND L5 GND L6 GND L7 GND M5 GND M6 GND M7
SGND
B3
SGND
C2
SGND
C3 PLLIN A3
COMP
C1
EXTVCC C4
C15 1uF 10V 0805 C15 1uF 10V 0805
JP6
1.5V
JP6
1.5V
E4
VOUT
E4
VOUT
R14 69.8k R14 69.8k
C9 1210 OPT C9 1210 OPT
+
C14 330uF 6.3V 7343
+
C14 330uF 6.3V 7343
R5 60.4k R5 60.4k
R2
100k
R2
100k
C11 OPT
1210
C11 OPT
1210
R4
3.16k
R4
3.16k
JP2
TRACK/SS
TRACK
SS
JP2
TRACK/SS
TRACK
SS
1 3 2
C7
10uF
35V 1210 C7
10uF
35V 1210
R6 OPT R6 OPT
JP1
FREQ
EXT CLK
INT CLK
JP1
FREQ
EXT CLK
INT CLK
1 3 2
C23 OPT C23 OPT
C18 1uF 10V C18 1uF 10V
E6
GND
E6
GND
C10 OPT
1210
C10 OPT
1210
C8 1210 OPT C8 1210 OPT
C2
OPT
C2
OPT
+
C5 150uF 35V
SANYO
+
C5 150uF 35V
SANYO
R1 121k R1 121k
D1 BZX84C4V7 D1 BZX84C4V7
31
R7 10k R7 10k
E10
CLKIN
E10
CLKIN
JP3
CCM
BURST/EXT CLK PULSE SKIP
MODE/CLK SEL
JP3
CCM
BURST/EXT CLK PULSE SKIP
MODE/CLK SEL
1 3 2 4
R12 OPT R12 OPT
R15 10k R15 10k
R8 OPT R8 OPT
JP10
5V
JP10
5V
Q1
SUD50N03
Q1
SUD50N03
3
1
2
C22 OPT C22 OPT
R10
OPT
R10
OPT
C21 OPT C21 OPT
E5
GND
E5
GND
E8
IOSTEP
CLK
E8
IOSTEP
CLK
J5
VOUT
J5
VOUT
J4
GND
J4
GND
C24 OPT C24 OPT
JP9
3.3V
JP9
3.3V
J2
GND
J2
GND
R13
0
R13
0
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DEMO MANUAL DC1472A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2010
LT 1010 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union direc-
tive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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