Linear Technology DC2249B Quick setup guide

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DEMO MANUAL DC2249B
Description
LTM4622EV
Ultrathin Dual 2.5A Step-Down
µModule Regulator
Demonstration circuit 2249B features the LT M
®
4622EV
µModule
®
regulator, a tiny low profile high performance
high efficiency dual step-down regulator. The LTM4622
has an operating input voltage range of 3.6V to 20V and
is able to provide an output current of up to 2.5A for each
channel.Eachoutput’svoltageisprogrammablefrom0.6V
to 5.5V. The LTM4622 is a complete DC-DC point of load
regulator in a low profile thermally enhanced 6.25mm ×
6.25mm× 1.82mm LGA package requiring only a few input
and output capacitors. Output voltage tracking is available
through the TRACK/SS pin for supply rail sequencing. L, LT, LTC, LTM, Linear Technology, µModule, Burst Mode and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
performance summary
External clock synchronization is available through the
SYNC/MODE pin. For high efficiency at low load currents
the MODE pin jumper (JP3) selects the Burst Mode
®
op-
tion for operation in less noise sensitive applications. The
LTM4622 data sheet must be read in conjunction with this
demo manual for working on or modifying demo circuit
2249B.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2249B
Specifications are at TA= 25°C
PARAMETER CONDITIONS VALUE
Input Voltage Range 4V to 20V
Output Voltage VOUT1, VOUT2 Programmable with FB Pin Resistors 3.3VDC, 1.2VDC
Maximum Continuous Output Current Each
Phase
Derating is Necessary for Certain Operating Conditions. See
Data Sheet for Details
2.5ADC
Default Operating Frequency 1MHz
Efficiency VIN = 12V, VOUT1 = 3.3V, IOUT = 2.5A, fSW = 2MHz
VIN = 12V, VOUT2 = 1.2V, IOUT = 2.5A, fSW = 1MHz
87.5%. See Figure 2
76.7%. See Figure 2
BoarD photo

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DEMO MANUAL DC2249B
Quick start proceDure
Demonstration circuit 2249B is an easy way to evaluate
the performance of the LTM4622. Please refer to Figure 1
for test setup connections and follow the procedure below.
1. With power off, place the jumpers in the following posi-
tions for a typical application for 3.3VOUT and 1.2VOUT
rails:
JP1 JP2 JP3
RUN1 RUN2 MODE
ON ON CCM
2. Before powering up the input supply and loads, preset
the input voltage supply to be between 4V to 20V. Preset
the load current for each output rail to 0A.
3. With power off, connect the loads, input voltage supply
and meters as shown in Figure 1.
4. Turn on the input power supply. The output voltage me-
ters for each output rail should display the programmed
output voltage ± 2%.
5. Once the proper output voltages are established, ad-
just the load current on each rail within the 0A to 2.5A
range and observe each output rail’s load regulation,
efficiency, and other parameters.
6. To observe increased light load efficiency place the
mode pin jumper (JP3) in the BURST position.
Note: Demonstration circuit 2249B is designed to exhibit
the wide output voltage range of the LTM4622. In order
to keep inductor current ripple within reasonable limits
it is recommended to increase programmed switching
frequency for higher output voltages. The programmed
switching frequency for data provided in this manual is
consistent with switching frequency recommendations
corresponding to the programmed output voltage. Please
refer to the LTM4622 data sheet for more details regard-
ing recommended switching frequency for your particular
application.

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DEMO MANUAL DC2249B
Quick start proceDure
+
–
+–
+ –
A
LOAD
0A TO 2.5A
+
–
V
+
–
+–
A
LOAD
0A TO 2.5A
+
–
V
+
–
AVIN
+ –
V
DC2249b F01
Figure 1. Test Setup

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DEMO MANUAL DC2249B
Figure 2. Measured Supply Efficiency at 12VIN and 5VIN
Quick start proceDure
LOAD CURRENT (A)
0
EFFICIENCY (%)
95
90
75
85
80
70 10.5 2 2.51.5
LOAD CURRENT (A)
0
EFFICIENCY (%)
90
95
75
85
80
70 10.5 2
DC2249b F02
2.51.5
VOUT = 3.3V
(2MHz)
12VIN CCM 5VIN CCM
VOUT = 1.2V
(1MHz)
VOUT = 3.3V
(2MHz)
VOUT = 1.2V
(1MHz)

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DEMO MANUAL DC2249B
Figure 3. Measured Load Transient Response (1A to 2A Load Step) Figure 4. Measured Load Transient Response (1A to 2A Load Step)
Figure 5. Thermal Capture at Full Load Natural Convection
Quick start proceDure
VIN (V) VOUT (V) COUT
12 1.2 1 × 22µF + 1 × 47µF
VIN (V) VOUT1 (V), IOUT1 (A) VOUT2 (V), IOUT2 (A) fSW (MHz) TAMBIENT (°C)
12 3.3, 2.5 1.2, 2.5 2 22
VIN (V) VOUT (V) COUT
12 3.3 1 × 22µF + 1 × 47µF
VOUT: 50mV/DIV
1A DC

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DEMO MANUAL DC2249B
parts List
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C1 CAP, X5R, 2.2µF, 10V, 10%, 0603 MURATA, GRM188R61A225KE34D
2 2 C3, C13 CAP, X5R, 22µF, 25V, 20%, 0805 MURATA, GRM21BR61E226ME-44L
3 2 C16, C29 CAP, X5R, 22µF, 6.3V, 20%, 0805 MURATA, GRM21BR60J226ME39L
4 2 C20, C23 CAP, X5R, 47µF, 6.3V, 20%,1206 MURATA, GRM31CR60J476ME19L
5 2 C21, C24 CAP, X5R, 0.1µF, 25V, 10%, 0603 MURATA, GRM188R61E104KA01D
6 1 R11 RES, CHIP, 60.4k, 1/16W, 1%, 0603 VISHAY, CRCW060360K4FKEA
7 1 R20 RES, CHIP, 13.3k, 1/16W, 1%, 0603 VISHAY, CRCW060313K3FKEA
8 1 U1 IC, LTM4622EV, LGA 25-6.25X6.25 LINEAR TECHNOLOGY, LTM4622EV#PBF
Additional Demo Board Circuit Components
2 1 C2 CAP, X5R, 10µF, 25V, 10%, 0805 TAIYO YUDEN, TMK212BBJ106KGHT
4 3 C4, C6, C18 CAP, X5R, 1µF, 10V, 10%, 0603 MURATA, GRM188R61A105KA61D
5 0 C8, C15, C22, C28 CAP, 0603 OPTION
6 1 C10 CAP, X5R, 22µF, 25V, 10%, 7343 SANYO, 25TQC22MV
10 0 C17, C25 CAP, 7343 OPTION
18 1 Q1 XSTR, SUD50N04-8M8P-4GE3 MOSFET TO-252 VISHAY, SUD50N04-8M8P-4GE3
19 1 RS1 RES, CHIP, 0.05Ω, 1/4W, 1%, 1206 VISHAY, WSL1206R0500FEA
20 0 R2, R10, R12, R14, R16 TO
R19, R21, R22, R23, R26 TO
R29
CAP, 0603 OPTION
21 1 R3 RES, CHIP, 10k, 1/16W, 1%, 0603 VISHAY, CRCW060310K0FKEA
22 4 R9, R15, R24, R25 RES, CHIP, 100k, 1/16W, 1%, 0603 VISHAY, CRCW0603100KFKEA
24 1 R13 RES, CHIP, 0, 1/16W, 1%, 0603 VISHAY, CRCW06030000Z0EA
Hardware: For Demo Board Only
13 14 E1 TO E14 TESTPOINT, TURRET, 0.095" MILL-MAX, 2501-2-00-80-00-00-07-0
14 2 JP1, JP2 HEADER, 1X3 0.079 SULLINS, NRPN031PAEN-RC
15 1 JP3 HEADER, 2X3 0.079 SULLINS, NRPN032PAEN-RC
16 3 XJP1, XJP2, XJP3 SHUNT SAMTEC 2SN-BK-G
17 2 J1, J2 CONN, BNC, 5PINS CONNEX, 112404
28 4 STAND OFF STAND OFF, SNAP ON, 0.375" TALL KEYSTONE_8832

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DEMO MANUAL DC2249B
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
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B
B
A
A
4V - 20V
GND
ON
OFF
RUN 1
PGOOD1
1.2V / 2.5A MAX
*
C10, IS AN OPTIONAL CAPACITOR. IT IS INSERTED TO DAMPEN THE (POSSIBLE) RINGING VOLTAGE DUE TO LONG INPUT LEADS. ON A NORMAL, TYPICAL PCB, WITH SHORT TRACES, THE CAPACITOR IS NOT NEEDED.
VIN
DUAL 2.5A STEP-DOWN µMODULE REGULATOR
NOTE: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS AND CAPACITORS ARE 0603
TRACK2
TRACK1
3.3V / 2.5A MAX
ON
OFF
RUN 2
CLK SYNC CLK
PGOOD2
OPTIONAL JUMPERS FOR PARALLEL OPERATION
LE T SAM Y.
VIN
GND VOUT2 GND
VOUT1
GND
VIN VOUT2
COMP2
SS2
COMP1
SS1
VOUT1
RUN1
FB1 FB2 COMP1 COMP2 SS1 SS2 RUN1 RUN2 VOUT2
FB2
RUN2
FB1
VOUT1
INTVCC
VIN
INTVCC
VIN
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
1
LTM4622EV
Thursday, May 26, 2016 1 1
N/A
DEMO CIRCUIT 2249B
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
1
LTM4622EV
Thursday, May 26, 2016 1 1
N/A
DEMO CIRCUIT 2249B
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
1
LTM4622EV
Thursday, May 26, 2016 1 1
N/A
DEMO CIRCUIT 2249B
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
SAM Y.
PRODUCTION2 3-31-15
_
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
SAM Y.
PRODUCTION2 3-31-15
_
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
SAM Y.
PRODUCTION2 3-31-15
_
R28 OPT R28 OPT
C21 0.1uF C21 0.1uF
C11 OPT
1210
C11 OPT
1210
E2E2
R18
OPT
R18
OPT
E11E11
C13 22uF 0805 C13 22uF 0805
R11
60.4K
R11
60.4K
R15
100K
R15
100K
JP1JP1
1
2
3
E5E5
JP3
MODE
CCM
BURST
JP3
MODE
CCM
BURST 1 2
3 4
65
C15 OPT C15 OPT
C1
2.2uF
10V C1
2.2uF
10V
E4E4
C23 47uF 1206 C23 47uF 1206
R22 OPT R22 OPT
R29
OPT 1206
R29
OPT 1206
E8E8
C8
OPT
C8
OPT
R14 OPT R14 OPT
C3 22uF 25V 0805 C3 22uF 25V 0805
+
C17
OPT
*
+
C17
OPT
*
R13
0
R13
0
E14E14
C20 47uF 1206 C20 47uF 1206
C16 22uF 6.3V 0805 C16 22uF 6.3V 0805
C26 OPT 1210 C26 OPT 1210 C28
OPT C28 OPT
R21
OPT
R21
OPT
E10E10 E1E1 E9E9
R2 OPT R2 OPT
R24
100K
R24
100K
R27 OPT R27 OPT
R9 100K R9 100K
C22
OPT
C22
OPT
E7E7
+
C25 OPT
*
+
C25 OPT
*
R19 OPT R19 OPT
R25
100K
R25
100K
LTM4622EV
U1
LTM4622EV
U1
FREQ
C4
MODE
C5
FB2 A4
TRACK/SS2 A3
COMP2 A5
RUN1
D2
PGOOD1 D4
VOUT2 A1
VIN B3
VIN A2
INTVCC C3
VOUT1
D1
VIN D3
VOUT2 B1
GND
B5
GND
C1
GND
C2
GND
D5
VIN E2
VOUT1
E1
PGOOD2 B4
COMP1
E5
FB1
E4
RUN2 B2
TRACK/SS1
E3
E6E6
R20
13.3K
R20
13.3K
+
C10
22uF
25V
*
+
C10
22uF
25V
*
E13E13
JP2JP2
1
2
3
C2
10uF 25V 0805
C2
10uF 25V 0805
R12 OPT R12 OPT
C14 OPT 1210 C14 OPT 1210
R17 OPT R17 OPT
C24 0.1uF C24 0.1uF
R10
OPT
R10
OPT
R23 OPT R23 OPT
R16 OPT R16 OPT
E3E3
R26 OPT R26 OPT
C29
22uF 6.3V 0805
C29
22uF 6.3V 0805

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DEMO MANUAL DC2249B
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2017
LT 0217 • 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
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engineer.
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