Linear Technology LTM4616 Quick setup guide

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DEMO MANUAL DC1245A
Description
LTM4616
Dual 2.7VIN(MIN), 8A Step-Down
µModule Regulator
Demonstration circuit 1245A features the LT M
®
4616, the
high efficiency, high density, dual output switch mode
power module. The rated load current is 8A for each chan-
nel, while derating is necessary for certain VIN, VOUT, and
thermal conditions. By applying a clock signal to the CLKIN
pin, the module’s switchingfrequency may besynchronized
from 0.75MHz to 2.25MHz. The same clock frequency is
available at the CLKOUT pin with the phase relationship
between CLKIN and CLKOUT determined by the PHMODE
pin. This feature can be used notonly to reduce undesirable
L, LT, LTC, LTM, µModule, Linear Technology and the Linear logo are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
perForMAnce sUMMArY
BoArD photo
frequency harmonics but also to parallel the two channels
of LTM4616 or even multiple LTM4616s and LTM4608s to
provide higher output currents. The LTM4616 data sheet
must be read in conjunction with this demo manual prior
to working on or modifying demo circuit DC1245A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1245A
(TA= 25°C)
PARAMETER CONDITIONS VALUE
Input Voltage Range 2.7V to 5.5V
Output Voltage VOUT1
VOUT2
VIN = 3.3V, IOUT1 = 8A
IOUT2 = 8A
1.8 ±2%
1.2 ±2%
Maximum Continuous Output Current Derating Is Necessary for Certain VIN, VOUT, and Thermal
Conditions, See Data Sheet for Details
8ADC Each Channel
Default Operating Frequency 1.5MHz
Efficiency VIN = 5V, VOUT1 = 1.8V, VOUT2 = 1.2V, 8A Per Channel 77.5%, See Figure3 for More Information
Load Transient VIN = 3.3V, VOUT1 =1.8V; VOUT2 = 1.2V See Figures 4 and 5 for Details
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DEMO MANUAL DC1245A
qUick stArt proceDUre
Demonstration circuit 1245A is an easy way to evaluate
the performance of the LTM4616. Please refer to Figure1
for proper measurement equipment setup and follow the
procedure below:
1. Place jumpers in the following positions for a typical
1.8VOUT and 1.2VOUT application:
PHMODE2 MARGINING2 RUN2 MARGINING1
2PH NO ON NO
TRACK1 PHMODE1 MODE RUN1
DISABLED 2PH BURST ON
2. With power off, connect the input power supply, load
and meters as shown in Figure 1. Preset the load to 0A
and VIN supply within the 2.7V to 5.5V operating range.
3. Turn on the power at the input. The output voltage at
VO1+and VO1–should be 1.8V ±2% and the voltage
at VO2+and VO2–should be 1.2V ±2%.
4. Once the proper output voltage is established, adjust
the load within the operating range and observe the
output voltage regulation, ripple voltage, efficiency and
other parameters. To measure input and output ripple,
please refer to Figure 2 for proper setup.
5. To synchronize channel 1 to an external clock, please
apply the desired clock signal to CLKIN and SGND1.
The external clock signal should have amplitude of at
least 2V but less than VIN.
6. VOUT1 can track another supply connected at TP20 as
determined by resistors R6 and R17. VOUT2 is set up
to track VOUT1 in a manner determined by resistors
R15 and R16. By default both resistor pairs have been
selected to support coincident tracking. Please refer to
Figure 6 for reference.
Figure 1. Test Setup of DC1245A
Figure 2. Proper Scope Probe Placement
for Measuring Input or Output Ripple
Figure 3. Measured Overall Supply Efficiency with Different VIN
Overall Efficiency vs Load Current
INPUT OR OUTPUT CAPACITOR
LOAD CURRENT FOR EACH CHANNEL (A)
0
EFFICIENCY (%)
95
85
75
65
55
45
90
80
70
60
50
40
35 62
dc1245a F03
10
4 8
VIN = 3.3V, VO1 = 1.8V, VO2 = 1.2V
VIN = 5V, VO1 = 1.8V, VO2 = 1.2V
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DEMO MANUAL DC1245A
V
IN = 3.3V
V
OUT =1.8V
CONTINUOUS CURRENT MODE (CCM)
2A
TO 6A LOAD STEP
C
OUT = ×2 100µF CERAMIC (1210, X5R, 6.3V) +
22µF CERAMIC (0805, X5R, 6.3V)
C
FF1 = 47pF
VOUT
OVERSHOOT AND UNDERSHOOT = 172mV
dc1245a F04
V
IN = 3.3V
V
OUT =1.2V
CONTINUOUS CURRENT MODE (CCM)
2A TO 6A LOAD STEP
C
OUT = ×2 100µF CERAMIC (1210, X5R, 6.3V) +
22µF CERAMIC (0805, X5R, 6.3V)
C
FF2 = 0pF
VOUT
OVERSHOOT AND UNDERSHOOT = 128mV
dc1245a F05
qUick stArt proceDUre
Figure 4. Measured Load Transient Response for 1.8VOUT
(4A Step, 25% to 75%)
Figure 5. Measured Load Transient Response for 1.2VOUT
(4A Step, 25% to 75%)
Figure 6. Measured Tracking Performance of VOUT1 and VOUT2
(with 2A Load Current)
7. Channel 2 is set up to synchronize to the CLKOUT sig-
nal of channel 1. The default phase difference is 180°.
Please refer to data sheet for how to set up PHMODE1
and PHMODE2 for paralleling more than 2 channels.
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DEMO MANUAL DC1245A
pArts list
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 4 CIN1, CIN2, CO13, CO23 Capacitor, X5R, 22µF, 6.3V, 20%, 1206 AVX, 12066D226MAT2A
2 1 CIN4 Capacitor, OS-CON, 150µF, 10V, E7 Size Sanyo, 10SVPA150MAA
3 4 CO11, CO12, CO21, CO22 Capacitor, X5R, 100µF, 6.3V, 20%, 1210 AVX, 12106D107MAT2A
4 1 RSET1 Resistor, Chip, 4.99k, 1/16W, 1%, 0402 Vishay, CRCW04024K99FKED
5 1 RSET2 Resistor, Chip, 10k, 1/16W, 1%, 0402 Vishay, CRCW040210K0FKED
6 1 U1 IC LTM4616EV 144-Pin LGA Linear Technology, LTM4616EV
Additional Demo Board Circuit Components
1 0 CO14, CO15, CO24, CO25 (OPT) Capacitor, 1210-3743
2 2 R7, R5 Resistor, Chip, 100k, 1/16W, 5%, 0402 Vishay, CRCW0402100KJNED
3 0 R9, R11, R19 (OPT) Resistor, Chip, 0402
4 0 CTHP1, CTHP2, C1, CFF2, CSP (OPT) Capacitor, 0402
5 1 CFF1 Capacitor, C0G, 47pF, 50V, 10%, 0402 AVX, 04025A470KAT2A
6 1 R17 Resistor, Chip, 4.99k, 1/16W, 1%, 0402 Vishay, CRCW04024K99FKED
7 3 R15, R16, R6 Resistor, Chip, 10k, 1/16W, 1%, 0402 Vishay, CRCW040210K0FKED
8 1 R18 Resistor, Chip, 0, 1/16W, 0402 Vishay, CRCW04020000Z0ED
Hardware/Components (For Demo Board Only)
1 0 CIN3(OPT) Capacitor, 1210-3743
2 5 JP1, JP2, JP3-JP5 2 ×3, 0.079 Double Row Header Samtec, TMM103-02-L-D
3 3 JP6, JP7, JP9 Header 3-Pin 0.079 Single Row Samtec, TMM103-02-L-S
4 8 JP1-JP7, JP9 Shunt, 0.079" Center Samtec, 2SN-BK-G
5 15 TP1, TP2, TP7-TP10, TP12, TP14-TP18,
TP20-TP22
Testpoint, Turret, 0.094" Pbf Mill-Max, 2501-2-00-80-00-00-07-0
6 2 TP6, TP3 Stud, Test Pin PEM KFH-032-10
7 4 TP6, TP3 Nut, Brass Nuts #10-32 Any #10-32
8 2 TP6, TP3 Ring, Lug Ring #10 Keystone #10
9 2 TP6, TP3 Washer, Tin Plated Brass Any #10
10 4 TP4, TP5, TP11, TP13 Jack Banana Keystone, 575-4
11 4 (STAND-OFF) Stand-Off, Nylon 0.50" Keystone, 8833(SNAP ON)
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DEMO MANUAL DC1245A
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
scheMAtic DiAgrAM
VIN+
VIN-
VIN
GND
2.5V - 5.5V
PGOOD1 PGOOD2
HI
NO
LOW
BURST
(PULSE SKIPPING) PS
(CONTINUOUS) CON
ITH2
ITHM2
2PH (PHASE)
3PH (PHASE)
4PH (PHASE)
MARGINING1
MODE
PHMODE1
TRACK1
DISABLED ENABLED
RUN1
ON
OFF
TRACK
CLKIN
SGND1
VOUT1 GND1
VO1+
VO1-
VOUT2
VO2+
VO2-
GND2
HI
NO
4PH (PHASE)
LOW
MARGINING2
2PH (PHASE)
3PH (PHASE)
PHMODE2
CLKOUT VFB
ON
OFF
RUN2
1.8V @ 8A MAX
1.2V @ 8A MAX
IN LAYOUT, MANUALLY TIED ALL GND TOGETHER ON LAYER 2.
A
DC1245A
Friday, February 15,2008
11
J. Wu 3/7/07
M. Xie 3/7/07
Dual 8A High Density Step-Down Power Module
LTM4616EV
SIZE
SCALE:
CAGECODE DWGNO REV
SHEET OF
FILENAME:
TITLE
CONTRACT NO.
APPROVALS DATE
DRAWN
CHECKED APPROVED
ENGINEER
TECHNOLOGY
1630 McCarthyBlvd.
Milpitas, CA 95035
Phone: [phone] Fax: [phone]
THIS CIRC UIT IS PR OPR IETARY TOLINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
LINEAR TE CHNOLOGY HAS MADE A BEST EFFORT TO DESIGNA
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT R EMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PR OPE R AND RELIABL E OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION ANDPRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR R ELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEER ING FOR ASSISTANCE.
CUSTOMER NOTICE
VIN
ITH2 ITHM2
CLK
VOUT1
ITH2 ITHM2
MODE
MODE
VOUT2
VFB
VFB
VOUT1
CLK
SVIN1
SVIN1
SVIN1
SVIN1
SVIN1 SVIN1
SVIN2
SVIN2
SVIN2
SVIN2
SVIN2 VOUT1
VOUT1
VOUT2
VOUT2
TP13
TP6
JP5
12
3 5
6 4
PBS1
R16
10.0K
1%
CO15
opt
6.3V
JP2
*
12
3
5
6
4
PFB1
TP21
C1
opt
CTHP2
opt.
R7
100K
CIN1 22uF
6.3V
R18 0
CIN3
100uF
opt
TP16
JP4
12
3
56
4
TP2
CO24
opt
6.3V
JP7
1
2
3
R6
10K
*DC1245A STILL USES THE OLD METHOD TO DISABLE MARGINING. AN IMPROVED METHOD OF TYING THE MGN PIN TO A VOLTAGE DIVIDER WITH 50k RESISTORS FROM V
IN
TO GROUND IS RECOMMENDED NOW.
TP22
LTM4616EV U1
A1
A2
A3
A4
A5
A6
A7 A8
A12
B1
B2
B3
B4
B5
B6
B7
B8
B9
B10
B11
B12
A9
A10 A11
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
D1
D2
D3
D4
D5
D6
D7
D8
D9 D10
D11
D12
E1
E2
E3
E4
E5
E6
E7 E8
E9 E10 E11 E12
F1
F2
F3
F4
F5 F6 F7 F8
F9 F10
F11
F12
G1
G2
G3
G4
G5
G6 G7
G8
G9
G10
G11
G12
H1
H2
H3
H4
H5
H6
H7
H8
H9
H10
H11
H12
J1
J2
J3
J4
J5
J6
J7
J8
J9
J10
J11
J12
K1
K2
K3
K4
K5
K6
K7
K8 K9 K10
K11
K12
L9
L10
L11
L12
M9 M10
M11
M12
L1
L2
L3
L4
L6
L7
L5
L8
M1
M2
M3
M4
M5 M6 M7 M8
GND1
GND1
GND1
GND1
GND1
BSEL1 CLKIN1
MODE1
GND1
GND1
GND1
GND1
GND1
GND1
SW1
GND1
GND1
GND1
GND1
GND1
GND1
PHMODE1 MGN1
PGOOD1
VIN1
VIN1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
VIN1
VIN1
GND1
GND1
GND1
GND1
GND1
FB1
VOUT1
VOUT1
VOUT1
VOUT1
VIN1
VIN1
VIN1
VIN1
SVIN1
PLLFLTR1
ITHM1 TRACK1
VOUT1
VOUT1 VOUT1
VOUT1
VIN1
VIN1
VIN1
VIN1
SGND1
RUN1 CLKOUT1 ITH1
VOUT1
VOUT1
VOUT1
VOUT1
GND2
GND2
GND2
GND2
GND2
BSEL2
CLKIN2
MODE2
PHMODE2
MGN2
PGOOD2
GND2
GND2
GND2
GND2
GND2
GND2
SW2
GND2
GND2
GND2
GND2
GND2
GND2
VIN2
VIN2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
VIN2
VIN2
GND2
GND2
GND2
GND2
GND2
FB2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2 VOUT2
VOUT2
VOUT2 VOUT2
VIN2
VIN2
VIN2
VIN2
PLLFLTR2
ITHM2
SVIN2
TRACK2
VIN2
VIN2
VIN2
VIN2
SGND2
RUN2
CLKOUT2
ITH2
CO23
22uF
6.3V
TP8
CIN2 22uF
6.3V
TP1
R17
4.99K
CO12
100uF
6.3V
CO14
opt
6.3V
CFF2 opt
PFB2
TP4
CFF1 47pF
R11 opt
CO22 100uF
6.3V
R19
opt
TP10
JP1
*
1 2
3
5 6
4
TP18
TP7
CSP
opt
TP5
TP14
TP20
R9 opt
TP3
TP12
CTHP1
opt.
TP15
CO21
100uF
6.3V
CO25
opt
6.3V
TP11
RSET2 10.0K 1%
PBS2
RSET1
4.99K
R15
10.0K
1%
TP17
CO13
22uF 6.3V
R5
100K
JP3
1 2 3 56
4
JP6
1
2
3
CO11 100uF
6.3V
+
CIN4
150uF 10V
JP9
1
2
3
TP9
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DEMO MANUAL DC1245A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2011
LT 0913 REV A • 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
directive 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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