Linear Technology DC1811B-A Quick setup guide

1
dc1811baf
DEMO MANUAL DC1811B-A
DESCRIPTION
LTM4676
Dual Step-Down µModule
Regulator with PMBus Digital
Power System Management
Demonstration circuit 1811B-A is a dual-output, high
efficiency, high density, µModule
®
regulator with 4.5V to
26.5V input range. Each output can supply 13A maximum
load current. The demo board has a LT M
®
4676 µModule
regulator, which is a dual 13A or single 26A step-down
regulator with PMBus power system management. Please
see LTM4676 data sheet for more detailed information
TheDC1811B-Apowersuptodefaultsettingsandproduces
power based on configuration resistors without the need for
any serial bus communication. This allows easy evaluation
of the DC/DC converter. To fully explore the extensive power
system management features of the part, download the GUI
software LTpowerPlay™ onto your PC and use LT C ’s I2C/
SMBus/PMBus dongle DC1613A to connect to the board.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
LTpowerPlay is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
BOARD PHOTO
Figure 1. Dual-Output LTM4676/DC1811B-A Demo Circuit
LTpowerPlay allows the user to reconfigure the part on the
fly and store the configuration in EEPROM, view telemetry
of voltage, current, temperature and fault status
GUI Download
The software can be downloaded from:
http://www.linear.com/ltpowerplay
For more details and instructions of LTpowerPlay, please
refer to LTpowerPlay GUI for LTM4676 Quick Start Guide.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1811BA

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dc1811baf
DEMO MANUAL DC1811B-A
QUICK START PROCEDURE
PERFORMANCE SUMMARY
(TA= 25°C)
PARAMETER CONDITION VALUE
Input Voltage Range 4.5V to 26.5V
Output Voltage, VOUT0 VIN = 4.5V to 26.5V, IOUT0 = 0A to 13A 0.5V to 4V, Default: 1V
Maximum Output Current, IOUT0 VIN = 4.5V to 26.5V, VOUT = 0.5V to 4V 13A
Output Voltage, VOUT1 VIN = 4.5V to 26.5V, IOUT1 = 0A to 13A 0.5V to 5.4V, Default: 1.8V
Maximum Output Current, IOUT1 VIN = 4.5V to 26.5V, VOUT = 0.5V to 5.4V 13A
Typical Efficiency VIN = 12V, VOUT = 1.8V, IOUT = 13A 86.3%
Default Switching Frequency 500kHz
Demonstration circuit 1811B-A is easy to set up to evalu-
ate the performance of the LTM4676. Refer to Figure 2
for the proper measurement equipment setup and follow
the procedure below.
1. With power off, connect the input power supply to VIN
(4.5V to 26.5V) and GND (input return).
2. Connect the 1.0V output load between VOUT0 and GND
(Initial load: no load).
3. Connect the 1.8V output load between VOUT1 and GND
(Initial load: no load).
4. Connect the DVMs to the input and outputs. Set default
jumper position: JP1: ON; JP2: ON.
5. Turn on the input power supply and check for the proper
output voltages. VOUT0 should be 1.0V±1 %, and VOUT1
should be 1.8 ±1%.
6. Oncetheproperoutputvoltagesareestablished,adjustthe
loads within the operating range and observe the output
voltage regulation, ripple voltage and other parameters.
7. Connect the dongle and control the output voltages
from the GUI. See “LTpowerPlay GUI for the LTM4676
Quick Start Guide” for details.
Note: When measuring the output or input voltage rip-
ple, do not use the long ground lead on the oscilloscope
probe. See Figure 3 for the proper scope probe technique.
Short, stiff leads need to be soldered to the (+) and (–)
terminals of an output capacitor. The probe’s ground ring
needs to touch the (–) lead and the probe tip needs to
touch the (+) lead.
Connecting a PC to DC1811B-A
You can use a PC to reconfigure the power management
features of the LTM4676 such as: nominal VOUT, margin
setpoints, OV/UVlimits,temperaturefaultlimits,sequenc-
ing parameters, the fault log, fault responses, GPIOs and
other functionality. The DC1613A dongle may be plugged
when VIN is present.
Table 1. LTM4676 Demo Cards for Up to 130A Point-of-Load Regulation
MAXIMUM OUTPUT CURRENT NUMBER OF OUTPUT VOLTAGES
NUMBER OF LTM4676 µMODULE
REGULATORS ON THE BOARD DEMO BOARD NUMBER
13A, 13A 2 1x LTM4676 DC1811A/DC1811B-A
13A, 13A 2 1x LTM4676A DC1811B-B
26A 1 1x LTM4676 DC2087A
50A 1 2x LTM4676 DC1989A-A
75A 1 3x LTM4676 DC1989A-B
100A 1 4x LTM4676 DC1989A-C
100A 1 1x LTM4676 (+ 3x LTM4620A) DC2106A-A
130A 1 1x LTM4676 (+ 3x LTM4630) DC2106A-B

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dc1811baf
DEMO MANUAL DC1811B-A
QUICK START PROCEDURE
-
VIN
4.5V26.5V A
V
+
-
+
+ -
A
+ -
Load0(0~13A)
V
+ -
Vout0
A +
-
Load1(0~13A)
V +
-
Vout1
Figure 2. Proper Measurement Equipment Setup
+ –
VOUT GND
COUT
Figure 3. Measuring Output Voltage Ripple

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dc1811baf
DEMO MANUAL DC1811B-A
QUICK START PROCEDURE
USBtoI2C/PMBus
DongleDC1613A
LTM4676Demo
BoardDC1811BA
InputPower
Supply
USBCable VIN
12PIN(J1)
Connector
Load0
Vout0
Vout1
Load1
Figure 4. Demo Setup with PC
LOAD CURRENT (A)
0
65
EFFICIENCY (%)
70
80
85
90
6 7 8 109 11 12
100
DC1811A F05
75
12345 13
95
VOUT = 1V
VOUT = 1.2V
VOUT = 1.5V
VOUT = 1.8V
VOUT = 2.5V
VOUT = 3.3V
VIN = 5V, fSW = 500kHz, CCM
Figure 5. Efficiency vs Load Current at VIN = 5V Figure 6. Efficiency vs Load Current at VIN = 12V
LOAD CURRENT (A)
0
65
60
EFFICIENCY (%)
70
80
85
90
6 7 8 109 11 12
DC1811A F06
75
12345 13
95
VOUT = 1V
VOUT = 1.2V
VOUT = 1.5V
VOUT = 1.8V
VOUT = 2.5V
VOUT = 3.3V
VOUT = 5V
VIN = 12V
fSW = 500kHz
CCM

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dc1811baf
DEMO MANUAL DC1811B-A
QUICK START PROCEDURE
VOUT0
(20MHz BW)
50mV/DIV
9.75A TO 13A
LOAD STEP
Figure 7. Output Voltage VOUT0 vs Load Current
(VOUT0 RANGE = 0)
Figure 8. Output Voltage VOUT1 vs Load Current
(VOUT1 Range = 1)
VOUT1
(20MHz BW)
50mV/DIV
9.75A TO 13A
LOAD STEP
VOUT0
(20MHz BW)
10mV/DIV
Figure 9. Output Voltage Ripple at VIN = 12V,
VOUT0 = 1V, IOUT0 = 13A
Figure 10. Output Voltage Ripple at VIN = 12V,
VOUT1 = 1.8V, IOUT1 = 13A
VOUT1
(20MHz BW)
10mV/DIV
Figure 11. Thermal performance at VIN = 12V, VOUT0 = 1.0V, IOUT0 = 13A, VOUT1 = 1.8V, IOUT1 = 13A, TA = 24°C, 200LFM Airflow

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dc1811baf
DEMO MANUAL DC1811B-A
LTpowerPlay SOFTWARE GUI
LTpowerPlay is a powerful Windows-based development
environment that supports Linear Technology power sys-
tem management ICs, including the LTM4676, LTC3880,
LTC3883, LTC2974 and LTC2978. The software supports
a variety of different tasks. You can use LTpowerPlay to
evaluate Linear Technology ICs by connecting to a demo
board system. LTpowerPlay can also be used in an offline
mode (with no hardware present) in order to build a mul-
tichip configuration file that can be saved and reloaded at a
latertime.LTpowerPlay provides unprecedenteddiagnostic
and debug features. It becomes a valuable diagnostic tool
during board bring-up to program or tweak the power
management scheme in a system, or to diagnose power
issues when bringing up rails. LTpowerPlay utilizes the
DC1613A USB-to-SMBus controller to communicate with
one of many potential targets, including the LTM4676, the
LTC3880 and the LTC3883’s demo system, or a customer
board. The software also provides an automatic update
feature to keep the soft-ware current with the latest set
of device drivers and documentation. The LTpowerPlay
software can be downloaded from:
http://www.linear.com/ltpowerplay
To access technical support documents for LT C Digital
Power Products visit Help. View online help on the
LTpowerPlay menu.
Figure 12. LTpowerPlay Main Interface

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dc1811baf
DEMO MANUAL DC1811B-A
LTpowerPlay QUICK START GUIDE
Thefollowingprocedure describes howtouseLTpowerPlay
to monitor and change the settings of LTM4676.
1. Download and install the LTPowerPlay GUI:
http://www.linear.com/ltpowerplay
2. Launch the LTpowerPlay GUI.
a. TheGUIshould automatically identify theDC1811B-A.
The system tree on the left hand side should look
like this:
b. A green message box shows for a few seconds in
the lower left hand corner, confirming that LTM4676
is communicating:
c. In the Toolbar, click the “R” (RAM to PC) icon to
read the RAM from the LTM4676. This reads the
configuration from the RAM of LTM4676 and loads
it into the GUI.
Then, click the “W” (PC to RAM) icon to write these
registervaluestotheLTM4676.Afterfinishingthisstep,
you will see the output voltage will change to 1.5V.
Ifthewrite issuccessful,youwill seethefollowingmessage:
e. You can save the changes into the NVM. In the tool
bar, click “RAM to NVM” button, as following
f. Save the demo board configuration to a (*.proj)
file. Click the Save icon and save the file. Name it
whatever you want.
d. If you want to change the output voltage to a different
value, like 1.5V. In the Config tab, type in 1.5 in the
VOUT_COMMAND box, like this:

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dc1811baf
DEMO MANUAL DC1811B-A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 CIN1 CAP., 150µF, 35V, ALUMINUM ELECTR., SUN ELECT., 35CE150AX
2 4 CIN2, CIN3, CIN4, CIN5 CAP., X5R, 10µF, 35V, 10%,1210 MURATA, GRM32ER6YA106KA12
3 6 COUT1-COUT3, COUT6-COUT8 CAP., X5R, 100µF, 6.3V, 20%, 1210 AVX, 12106D107MAT2A
4 2 COUT4, COUT5 CAP., 330µF, 6.3V, POSCAP, D3L PANASONIC, 6TPF330M9L
5 2 C1, C14 CAP., X7R, 2200pF, 25V, 10%, 0603 AVX, 06033C222KAT2A
6 1 C26 CAP., X5R, 100nF, 16V, 10%,0603 AVX, 0603YD104KAT2A
7 2 C27, C28 CAP., X5R, 10nF, 16V, 10%,0603 AVX, 0603YD103KAT2A
8 1 C23 CAP., X7R, 1µF, 25V,10%, 0805 AVX, 08053C105KAT2A
9 3 C21, C22, C24 CAP., X5R, 1µF, 25V,10%, 0603 AVX, 06033D105KAT2A
10 2 JP1, JP2 HEADER 3 PIN 0.079 SINGLE ROW SULLIN, NRPN031PAEN-RC
11 3 J2-J4 CONN, BNC, 5PINS CONNEX, 112404
12 1 J1 CONN HEADER 12POS 2Mm STR DL PCB FCI, 98414-G06-12ULF
13 6 J5-J10 BANANA JACK KEYSTONE, 575-4
14 1 Q1 N-Channel 30-V Mosfet VISHAY, SUD50N04-8M8P-4GE3
15 1 D8 DIODE, ULTRA LOW SCHOTTKY RECTIFIER NXP SEMI., PMEG2005AEL
16 1 Q19 P-Channel 30-V Mosfet DIODES INC., DMP3130L-7
17 1 J11 CONN RECEPT 2mm DUAL R/A 14POS (F) SULLINS, NPPN072FJFN-RC
18 1 J12 HEADER 14POS 2mm R/A GOLD (M) MOLEX, 87760-1416
19 1 J13 HEADER, 4 PINS, SHROUDED HIROSE, DF3A-4P-2DSA
20 10 R3, R5, R7, R9, R25, R31, R32, R63, R65, R66 RES., CHIP, 0Ω, 1%, 0603 NIC, NRC06ZOTRF
21 2 R69, R70 RES., CHIP, 10, 1%, 0603 NIC, NRC06F10R0TRF
22 12 R10-R16, R18, R19, R24, R52, R77 RES., CHIP, 10K, 1%, 0603 NIC, NRC06F1002TRF
23 1 R78 RES., CHIP, 15.8K, 1%, 0603 NIC, NRC06F1582TRF
24 1 R30 RES., CHIP, 6.34K, 1%, 0603 VISHAY, CRCW06036K34FKEA
25 3 R2, R72, R73 RES., CHIP, 4.99K, 1%, 0603 NIC, NRC06F4991TRF
26 1 R22 RES., CHIP, 4.22K, 1%, 0603 VISHAY, CRCW06034K22FKEA
27 1 R48 RES., CHIP, 0Ω, 0.5W, 2010 NIC, NRC50ZOTRF
28 1 R53 RES., CHIP, 0.01Ω, 1/2W, 1%, 2010 VISHAY, WSL2010R0100FEA
29 1 U3 IC, 24LC025-I/ST, SOIC MICROCHIP, 24LC025-I/ST
30 1 U1 IC, LTM4676EY#PBF LINEAR TECH., LTM4676EY#PBF
Additional Demo Board Circuit Components
1 0 C2, C15-C17(OPT) CAP., 0603
2 0 D1, D2 (OPT) DIODE, SOD-323
3 0 R4, R6, R8, R20, R23, R26-R29, R33, R35, R37,
R38, R41, R49, R61, R62, R64, R67, R68, R74,
R75, R82, R83, R88, R89 (OPT)
RES., OPTIONAL
4 0 R50, R51(OPT) RES., CHIP, 30, 1%, 2512
Hardware-For Demo Board Only
1 24 E1-E17, E20-E24, E28, E29 TESTPOINT, TURRET, 0.062" MILL-MAX, 2308-2-00-80-00-00-07-0
2 2 XJP1, XJP2 SHUNT SAMTEC, 2SN-BK-G
34 (STAND-OFF) STAND-OFF, NYLON 0.50" tall (SNAP ON) KEYSTONE, 8833
4 1 FAB, PRINTED CIRCUIT BOARD DEMO CIRCUIT 1811B-A

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dc1811baf
DEMO MANUAL DC1811B-A
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B
B
A
A
NOTE: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS ARE 0603. ALL CAPACITORS ARE 0603.
35V
4.5V - 26.5V
1.0V / 13A
6.3V
6TPF330M9L
1.8V / 13A
ON
ON
6.3V
6TPF330M9L
1210 1210 1210
OPT
0805
OFF
1210 1210 1210 1210
1210 1210 1210
0.035 VIA TESTPOINTS
WITH POWER SYSTEM MANAGEMENT
*
WHEN VIN < 5.75V, SHORT INTVCC TO VIN WITH R8 = 0ohm.
*
U1
B - A B - B
LTM4676EY LTM4676AEY
*
*
VOSNS0+
VOSNS0-
VDD33
SYNC SHARE_CLK ALERTB SCL SDA GPIO0B GPIO1B ASEL FREQ_CFG VOUT0_CFG VTRIM0_CFG VOUT1_CFG VTRIM1_CFG RUN1 VDD25 RUN0 INTVCC
VOSNS1
VIN
VOUT0
VOUT1
VIN
SYNC SHARE_CLK
ALERTB
SCL SDA
GPIO0B
GPIO1B
COMP0a
COMP1a
RUN0 RUN1
VDD33
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
Friday, October 24, 2014
13
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
B
LTM4676EY + LTM4676AEY DEMO CIRCUIT 1811B
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
Friday, October 24, 2014
13
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
B
LTM4676EY + LTM4676AEY DEMO CIRCUIT 1811B
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
Friday, October 24, 2014
13
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
B
LTM4676EY + LTM4676AEY DEMO CIRCUIT 1811B
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
JIAN L.PRODUCTION1 6-2-14
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
JIAN L.PRODUCTION1 6-2-14
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
JIAN L.PRODUCTION1 6-2-14
__
E13
GPIO0B
E13
GPIO0B
E4
VIN
E4
VIN
COUT1 100uF COUT1 100uF
CIN3 10uF CIN3 10uF
J7
VOUT0 J7 VOUT0
R18 10K R18 10K
CIN2 10uF CIN2 10uF
R9 0R9 0 E9
SYNC
E9
SYNC
R10 10K R10 10K
R7 0R7 0
E17
GND0_SNS
E17
GND0_SNS
R4
OPT
R4
OPT
R33 OPT R33 OPT
COUT7
100uF
COUT7
100uF
R8 OPTR8 OPT
C2
OPT
C2
OPT
J10
VIN
J10
VIN
CIN5 10uF CIN5 10uF
J5
GND
J5
GND
E16
VDD25
E16
VDD25
R14 10K R14 10K
R32 0R32 0
COUT8
100uF
COUT8
100uF
C14
2200pF
C14
2200pF
C1
2200pF
C1
2200pF
+
COUT5 330uF
+
COUT5 330uF
P1P1
R24 10K R24 10K
U1
LTM4676EY / LTM4676AEY
U1
LTM4676EY / LTM4676AEY
VOUT0
A1
VOUT0
A2
VOUT0
A3
VOUT0
D1
ISNS0b-
E1
ISNS0b+
F1
ISNS1b- G1
ISNS1b+ H1
VOUT1 J1
VOUT1 J2
VOUT1 J3
VOUT1 K1
VOUT0
B1
VOUT0
B2
VOUT0
B3
VOUT0
D2
ISNS0a-
E2
ISNS0a+
F2
ISNS1a- G2
ISNS1a+ H2
VOUT1 K2
VOUT1 K3
VOUT1 L1
VOUT1 L2
VOUT0
C1
VOUT0
C2
VOUT0
C3
VOUT0
D3
GND
A4
GND
A6
GND
A7
GND
A8
VOUT1 L3
VOUT1 M1
VOUT1 M2
VOUT1 M3
GND
A9
GND
A10
GND
B4
GND
B5
ASEL G4
FSWPHCFG H4
GND
B6
GND
B7
GND
B8
GND
B9
GPIO0 E4 GPIO1 F4
SNUB0
A5
GND
C4
TSNS0b
C5
TSNS0a
D5
ALERT E5
RUN0 F5
VOUT0CFG G5
VTRIM0CFG H5
TSNS1a J5
TSNS1b K5
GND
C6
SNUB1 M5
GND
C7
GND
C8
GND
C9
SDA D6
SCL E6
RUN1 F6
VOUT1CFG G6
VTRIM1CFG H6
VDD25 J6
WP K6
GND
D4
GND
E3
GND
F3
GND
F10
GND
G3
GND
G10
SYNC E7
GND
M9
GND
M10
SHARE_CLK H7
VDD33 J7
GND
G11
GND
G12
GND
L8 GND
L7
GND
L9
GND
H3
COMP0b
D8
COMP0a
E8
SGND
F7
SGND
F8
COMP1a H8
COMP1b J8
GND
H10
GND
J4
GND
M8
VOSNS0+
D9
VOSNS0-
E9
INTVCC F9 INTVCC G9
VOSNS1 H9
VORB1 J9
GND
J10
GND
L4
GND
L5
GND
K4
SW0
B10
DNC
E11
VORB0+
D10
VORB0-
E10
GND
L6
GND
K7
GND
K8
GND
K9
DNC
C10
SW1 L10
GND
M4
VINH0
B12 VINH0 B11 VINH0 A12 VINH0 A11
DNC
K10
VINL
F12
GND
M6
DNC
H11
VINH1 H12
VINH1 J11
VINH1 J12
VINH1 K11
VINH0
E12 VINH0
D12 VINH0 D11 VINH0 C12 VINH0 C11
VINL
F11
GND
M7
VINH1 K12
VINH1 L11
VINH1 L12
VINH1 M11
VINH1 M12
SGND
G7
SGND
G8
GND
D7
R30 6.34KR30 6.34K
E7
GND1_SNS
E7
GND1_SNS
R29 (OPT) R29 (OPT)
R16 10K R16 10K
E8
VDD33
E8
VDD33
COUT6
100uF
COUT6
100uF
E12
SDA
E12
SDA
C15 OPT C15 OPT
R20
0805
R20
0805
P2P2
J8
GND
J8
GND
R25
0
R25
0
P4P4
C17 OPT C17 OPT
R11 10K R11 10K
+
COUT4
330uF
+
COUT4
330uF
R19 10K R19 10K
P5P5
R23 OPTR23 OPT
R3 0 R3 0
E14
GPIO1B
E14
GPIO1B
COUT3 100uF COUT3 100uF
E15
VOUT0_SNS E15 VOUT0_SNS
COUT2 100uF COUT2 100uF
J9
GND
J9
GND
R6 OPT R6 OPT
R27 (OPT)R27 (OPT)
E3
INTVCC
E3
INTVCC
+
CIN1 150uF
+
CIN1 150uF
R15 10K R15 10K
R5 0 R5 0
R2 4.99K R2 4.99K
E1
VOUT1_SNS
E1
VOUT1_SNS
E10
ALERTB
E10
ALERTB
JP1
RUN0
JP1
RUN0
1 3 2
R13 10K R13 10K
E11
SCL
E11
SCL
R22
4.22K
R22
4.22K
R12 10K R12 10K
E6
SHARE_CLK
E6
SHARE_CLK
P3P3
CIN4 10uF CIN4 10uF
JP2
OFF
RUN1
JP2
OFF
RUN1
1 3 2
R28 (OPT)R28 (OPT)
E2
GND
E2
GND
C16 OPT C16 OPT
J6 VOUT1 J6 VOUT1
R31 0R31 0 R26 (OPT)R26 (OPT)
E5
GND
E5
GND

10
dc1811baf
DEMO MANUAL DC1811B-A
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
ALL PARTS ON THIS PAGE ARE FOR DEMO ONLY, NOT NEEDED IN CUSTOMER DESIGN
OPT
2010 2010 OPT VOUT1
DYNAMIC LOAD CIRCUIT DO NOT EXCEED 5% DUTY CYCLE!
BLEEDER LOADS
OPTIONAL JUMPER FOR DUAL PHASE SINGLE OUTPUT CONFIGURATION
2010
WITH POWER SYSTEM MANAGEMENT
VOUT0 VOUT1
VOUT0 VOUT1
COMP0a COMP1a
GPIO0B GPIO1B
RUN0RUN1
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
Friday, October 24, 2014
23
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
N/A
LTM4676EY / LTM4676AEY DEMO CIRCUIT 1811B
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
Friday, October 24, 2014
23
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
N/A
LTM4676EY / LTM4676AEY DEMO CIRCUIT 1811B
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
Friday, October 24, 2014
23
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
N/A
LTM4676EY / LTM4676AEY DEMO CIRCUIT 1811B
R52 10K R52 10K
R38 OPTR38 OPT E22
GND
E22
GND
J3J3
1
2
3
4
5
R50R50
Q1
SUD50N04
Q1
SUD50N04
2
1
3
4
R49 2010 OPT R49 2010 OPT
J4
IOSTEP
J4
IOSTEP
1
2
3
4
5
E23
SGND
E23
SGND
R48 2010 0.5W
0
R48 2010 0.5W
0
R35 OPTR35 OPT
J2
VOUT0
J2
VOUT0
1
2
3
4
5
C24 1uF C24 1uF
C22 1uF C22 1uF
R41 OPT.R41 OPT.
E20
IOSTEP_CLK
E20
IOSTEP_CLK
R51R51
E24
SGND E24 SGND
C21 1uF C21 1uF
R53
0.01
R53
0.01
C23 1uF C23 1uF