Linear Technology Analog Devices LTM4676A Quick setup guide

1
DEMO MANUAL DC1811B-B
Rev. A
DESCRIPTION
LTM4676A
Dual Step-Down µModule
Regulator with PMBus Digital
Power System Management
Demonstration circuit 1811B-B 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
®
4676AµModule
regulator, which is a dual 13A or single 26A step-down
regulator with PMBus power system management. Please
see LTM4676A data sheet for more detailed information.
The DC1811B-B powers up to default settings and pro-
duces 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
BOARD PHOTO
Figure1. Dual-Output LTM4676A/DC1811B-B Demo Circuit
PC and use ADI’s I2C/SMBus/PMBus dongle DC1613A
to connect to the board. LTpowerPlay allows the user to
reconfigure the part on-the-fly and store the configuration
in EEPROM, view telemetry of voltage, current, tempera-
ture and fault status.
GUI Download
The software can be downloaded from: LTpowerPlay
For more details and instructions of LTpowerPlay, please refer
to LTpowerPlay GUI for LTM4676A Quick Start Guide.
Design files for this circuit board are available.
All registered trademarks and trademarks are the property of their respective owners.

2
DEMO MANUAL DC1811B-B
Rev. 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 5.5V (Minimum On)*, Default: 1V
Maximum Output Current, IOUT0 VIN = 4.5V to 26.5V, VOUT = 0.5V to 5.5V 13A
Output Voltage, VOUT1 VIN = 4.5V to 26.5V, IOUT1 = 0A to 13A 0.5V to 5.5V (Minimum On)*, Default: 1.8V
Maximum Output Current, IOUT1 VIN = 4.5V to 26.5V, VOUT = 0.5V to 5.5V 13A
Typical Efficiency VIN = 12V, VOUT = 1.8V, IOUT = 13A 86.3%
Default Switching Frequency 500kHz
*For low duty cycle applications, it may approach minimum on the limit. The minimum on-time for LTM4676A is 45ns nominal, guardband to 90ns.
Demonstration circuit 1811B-B is easy to set up to evalu-
ate the performance of the LTM4676A. 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 ±0.5 %,
and VOUT1 should be 1.8V ±0.5%.
6. Once the proper output voltages are established, adjust the
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 LTM4676A
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-B
You can use a PC to reconfigure the power management
features of the LTM4676A such as:nominal VOUT, mar-
gin set points, OV/UV limits, temperature fault limits,
sequencing parameters, the fault log, fault responses,
GPIOs and other functionality. The DC1613A dongle may
be plugged when VIN is present.
Table 1. LTM4676/LTM4676A Demo Cards for Up to 130A Point-of-Load Regulation
MAXIMUM OUTPUT CURRENT NUMBER OF OUTPUT VOLTAGES
NUMBER OF LTM4676/LTM4676A µMODULE
REGULATORS ON THE BOARD DEMO BOARD NUMBER
13A, 13A 2 1× LTM4676 DC1811A/DC1811B-A
13A, 13A 2 1× LTM4676A DC1811B-B
26A 1 1× LTM4676 DC2087A
50A 1 2× LTM4676 DC1989A-A
75A 1 3× LTM4676 DC1989A-B
100A 1 4× LTM4676 DC1989A-C
100A 1 1× LTM4676 (+ 3× LTM4620A) DC2106A-A
130A 1 1× LTM4676 (+ 3× LTM4630) DC2106A-B

3
DEMO MANUAL DC1811B-B
Rev. A
QUICK START PROCEDURE
Figure2. Proper Measurement Equipment Setup
+ –
VOUT GND
COUT
Figure3. Measuring Output Voltage Ripple
+
–
VIN
4.5V TO
26.5V
+–
+
–
LOAD1
(0A TO 13A)
VOUT1
+–
+
–
LOAD0
(0A TO 13A)
VOUT0
+–
+
–

4
DEMO MANUAL DC1811B-B
Rev. A
QUICK START PROCEDURE
USBtoI2C/PMBus
DongleDC1613A
LTM4676ADemo
BoardDC1811BB
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

5
DEMO MANUAL DC1811B-B
Rev. 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

6
DEMO MANUAL DC1811B-B
Rev. A
LTpowerPlay SOFTWARE GUI
LTpowerPlay is a powerful Windows-based development
environment that supports Analog Devices power sys-
tem management ICs, including the LTM4676A, LTC3880,
LTC3883, LTC2974 and LTC2978. The software supports
a variety of different tasks. You can use LTpowerPlay to
evaluate Analog Devices 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
later time. LTpowerPlay provides unprecedented diagnos-
tic 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 LTM4676A,
the LTC3880 and the LTC3883’s demo system, or a cus-
tomer 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:
LTpowerPlay
To access technical support documents for ADI Digital
Power Products visit Help. View online help on the
LTpowerPlay menu.
Figure12. LTpowerPlay Main Interface

7
DEMO MANUAL DC1811B-B
Rev. A
LTpowerPlay QUICK START GUIDE
The following procedure describes how to use LTpowerPlay
to monitor and change the settings of LTM4676A.
1. Download and install the LTPowerPlay GUI:
LTpowerPlay
2. Launch the LTpowerPlay GUI.
a. The GUI should automatically identify the
DC1811B-B. 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 LTM4676A is
communicating:
c. In the Toolbar, click the “R” (RAM to PC) icon to
read the RAM from the LTM4676A. This reads the
configuration from the RAM of LTM4676A and loads
it into the GUI.
Then, click the “W” (PC to RAM) icon to write these
register values to the LTM4676A. After finishing this
step, you will see the output voltage will change to 1.5V.
If the write is successful, you will see the following message:
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 what-
ever you want.
d. If you want to change the output voltage to a differ-
ent value, like 1.5V. In the Config tab, type in 1.5 in
the VOUT_COMMAND box, like this:

8
DEMO MANUAL DC1811B-B
Rev. 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., X7R, 10nF, 16V, 10%,0603 AVX, 0603YC103KAT2A
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, 5 PINS 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 40-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, 10k, 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, LTM4676AEY#PBF ANALOG DEVICES, LTM4676AEY#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
3 4 (STAND-OFF) STAND-OFF, NYLON 0.50" TALL (SNAP ON) KEYSTONE, 8833
4 1 FAB, PRINTED CIRCUIT BOARD DEMO CIRCUIT 1811B-B

9
DEMO MANUAL DC1811B-B
Rev. 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:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, December 01, 2014
1 3
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
B
LTM4676EY + LTM4676AEY DEMO CIRCUIT 1811B-A/B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, December 01, 2014
1 3
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
B
LTM4676EY + LTM4676AEY DEMO CIRCUIT 1811B-A/B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, December 01, 2014
1 3
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
B
LTM4676EY + LTM4676AEY DEMO CIRCUIT 1811B-A/B
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
JIAN L.PRODUCTION 41-2-61
__
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
JIAN L.PRODUCTION 41-2-61
__
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
JIAN L.PRODUCTION 41-2-61
__
J7
VOUT0 J7 VOUT0
CIN3 10uF CIN3 10uF
COUT1 100uF COUT1 100uF
E4
VIN
E4
VIN
E13
GPIO0B
E13
GPIO0B
R18 10K R18 10K
E17
GND0_SNS
E17
GND0_SNS
R7 0R7 0
R10 10K R10 10K
E9
SYNC
E9
SYNC
R9 0R9 0
CIN2 10uF CIN2 10uF
R8 OPTR8 OPT
COUT7
100uF
COUT7
100uF
R33 OPT R33 OPT
R4
OPT
R4
OPT
COUT8
100uF
COUT8
100uF
R32 0R32 0
R14 10K R14 10K
E16
VDD25
E16
VDD25
J5
GND
J5
GND
CIN5 10uF CIN5 10uF
J10
VIN
J10
VIN
C2
OPT
C2
OPT
E7
GND1_SNS
E7
GND1_SNS
R30 6.34KR30 6.34K
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
R24 10K R24 10K
P1P1
+
COUT5 330uF
+
COUT5 330uF
C1
2200pF
C1
2200pF
C14
2200pF
C14
2200pF
COUT6
100uF
COUT6
100uF
E8
VDD33
E8
VDD33
R16 10K R16 10K
R29 (OPT) R29 (OPT)
P4P4
R25
0
R25
0
J8
GND
J8
GND
P2P2
R20
0805
R20
0805
C15 OPT C15 OPT
E12
SDA
E12
SDA
+
COUT4
330uF
+
COUT4
330uF
R11 10K R11 10K
C17 OPT C17 OPT
R3 0 R3 0
R23 OPTR23 OPT
P5P5
R19 10K R19 10K
E15
VOUT0_SNS E15 VOUT0_SNS
COUT3 100uF COUT3 100uF
E14
GPIO1B
E14
GPIO1B
E3
INTVCC
E3
INTVCC
R27 (OPT)R27 (OPT)
R6 OPT R6 OPT
J9
GND
J9
GND
COUT2 100uF COUT2 100uF
R5 0 R5 0
R15 10K R15 10K
+
CIN1
150uF
+
CIN1
150uF
R13 10K R13 10K
JP1
RUN0
JP1
RUN0
1 3
2
E10
ALERTB
E10
ALERTB
E1
VOUT1_SNS
E1
VOUT1_SNS
R2 4.99K R2 4.99K
P3P3
E6
SHARE_CLK
E6
SHARE_CLK
R12 10K R12 10K
R22
4.22K
R22
4.22K
E11
SCL
E11
SCL
R28 (OPT)R28 (OPT)
JP2
OFF
RUN1
JP2
OFF
RUN1
1
3 2
CIN4 10uF CIN4 10uF
E5
GND
E5
GND
R26 (OPT)R26 (OPT) R31 0R31 0
J6 VOUT1 J6 VOUT1
C16 OPT C16 OPT
E2
GND
E2
GND

10
DEMO MANUAL DC1811B-B
Rev. A
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D D CC
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:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, December 01, 2014
2 3
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
N/A
LTM4676EY / LTM4676AEY
DEMO CIRCUIT 1811B-A/B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, December 01, 2014
2 3
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
N/A
LTM4676EY / LTM4676AEY
DEMO CIRCUIT 1811B-A/B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, December 01, 2014
2 3
DUAL STEP-DOWN uMODULE REGULATOR
HZ
JIAN L.
N/A
LTM4676EY / LTM4676AEY
DEMO CIRCUIT 1811B-A/B
E22
GND
E22
GND
R38 OPTR38 OPT
R52 10K R52 10K
Q1
SUD50N03-09P
Q1
SUD50N03-09P
2
1
3
4
R50R50
J3J3
1
2
3
4
5
R49 2010 OPT R49 2010 OPT
J4
IOSTEP
J4
IOSTEP
1
2
3
4
5
E23
SGND
E23
SGND
C22 1uF C22 1uF
C24 1uF C24 1uF
J2
VOUT0
J2
VOUT0
1
2
3
4
5
R35 OPTR35 OPT
R48 2010 0.5W
0
R48 2010 0.5W
0
E20
IOSTEP_CLK
E20
IOSTEP_CLK
R41 OPT.R41 OPT.
R51R51
E24
SGND E24 SGND
C21 1uF C21 1uF
R53
0.01
R53
0.01
C23 1uF C23 1uF