Analog Devices DC2652A-A User manual

1
DEMO MANUAL DC2652A-A
Rev. 0
DESCRIPTION
LTC3888
8-Phase, Dual-Output Synchronous Buck
Converter with Power System Management
Demonstration circuit 2652A-A is an 8-phase dual-output,
high efficiency, high density, synchronous buck converter
with 7V to 14V input range. Each output can supply up to
120A maximum load current with 1V output. The demo
board showcases the LT C
®
3888, which is a PMBus-
compliant dual loop 8-phase step-down DC/DC controller
with digital power system management. The LTC3888 is
designed to work with DrMOS devices that provide an out-
put current sense and temperature monitor. Please refer
to LTC3888’s data sheet for more detailed information.
DC2652A-A powers up to default settings and produces
power based on configuration resistors (or with the set-
ting in its non-volatile memory) without the need for any
serial bus communication. This allows easy evaluation of
All registered trademarks and trademarks are the property of their respective owners.
BOARD PHOTO
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 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, temperature and fault status.
GUI Download
The software can be downloaded from:
here
For more details and instructions of LTpowerPlay,
please refer to LTpowerPlay Quick Start Procedure.
Design files for this circuit board are available.
Figure1. Dual-Output LTC3888/DC2652A-A Demo Circuit

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DEMO MANUAL DC2652A-A
Rev. 0
QUICK START PROCEDURE
DC2652A-A is easy to set up to evaluate the performance
of LTC3888. Refer to Figure2 for the proper measurement
equipment setup and follow the procedure below.
1. With power off, connect the input power supply
(7V-14V) to VIN (J1) and GND (J2).
2. Connect the 1.0V output load (Initial load: no load)
between VOUT0 (J3) and GND (J4).
3. Connect the 1.0V output load (Initial load: no load)
between VOUT1 (J5) and GND (J6).
4. ConnecttheDMMstotheinputandoutputs.Setdefault
jumper position:
• JP1: ON
• JP2: EXT
• JP3: SLAVE
• JP4: SLAVE
• SW1: ON
• SW2: 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 1.0V ±0.5%.
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 Quick Start Procedure
for details.
Note:
1. When measuring the efficiency, it is recommended
to monitor the VIN, VOUT0 and VOUT1 at the locations
close to the power stage. Here are examples:
(1) Monitor VIN across CIN9 and VOUT0 across COUT11
for VOUT0 efficiency measurement
(2) MonitorVIN acrossCIN29 and VOUT1across COUT31
for VOUT1 efficiency measurement
2. When measuring the output or input voltage ripple,
do not use the long ground lead on the oscilloscope
probe. 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.
3. Whendoing theloadtransienttest, itisrecommendedto
use a function generator to generate a pulse (~3% duty
cycle with 10Hz~100Hz frequency). Then applying this
pulse to the EXT PULSE (E9) and GND (E10) turrets, the
dynamic load circuit will work well to achieve desired
load transient test by adjusting the amplitude, rising
edge and falling edge of the pulse. Here are examples:
(1) Set the amplitude of the pulse to 3.4V for a 0A to 30A
load transient test with 10mΩ IOUT sensing resistor
(2) Set the amplitude of the pulse to 3.6V for a 0A to 40A
load transient test with 10mΩ IOUT sensing resistor
PERFORMANCE SUMMARY
Specifications are at TA= 25°C
PARAMETER CONDITIONS VALUE
Input Voltage Range 7V to 14V
Output Voltage, VOUT0 VIN = 7 to 14V, IOUT0 = 0A to 120A 0.3 to 1.8V, Default: 1.0V
Maximum Output Current, IOUT0 VIN = 7 to 14V, VOUT0 = 0.3V to 1.8V 120A
Output Voltage, VOUT1 VIN = 7 to 14V, IOUT1 = 0A to 120A 0.3 to 1.8V, Default: 1.0V
Maximum Output Current, IOUT1 VIN = 7 to 14V, VOUT1 = 0.3V to 1.8V 120A
Typical Efficiency of VOUT0 VIN = 12V, VOUT0 = 1.0V, IOUT0 = 120A 91.7%
Typical Efficiency of VOUT1 VIN = 12V, VOUT1 = 1.0V, IOUT1 = 120A 91.7%
Default Switching Frequency 500kHz

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DEMO MANUAL DC2652A-A
Rev. 0
QUICK START PROCEDURE
Figure2. Proper Measurement Equipment Setup
Figure3. Measuring Output Voltage Ripple
+
–
+
–
VOUT0
IOUT0
IOUT1
VOUT1
+–
+–
+–
+–
V
IN
IIN
POWER
SUPPLY
+–
+
–
LOAD0
–
+
LOAD1
DC2652A-A F02
+ –
V
OUT
GND
COUT

4
DEMO MANUAL DC2652A-A
Rev. 0
QUICK START PROCEDURE
Connecting a PC to DC2652A-A
You can use a PC to reconfigure the power management
features of LTC3888 such as:nominal VOUT, margin set
points, OV/UV limits, temperature fault limits, sequenc-
ing parameters, the fault log, fault responses, GPIOs
and other functionalities. The DC1613A dongle may be
plugged when VIN is present.
USB CABLE VIN
VOUT0
LOAD0
LOAD1
V
OUT1
12-PIN (J12)
CONNECTOR
USB TO I2C/PMBUS
DONGLE DC1613A
INPUT POWER
SUPPLY
LTC3888 DEMO BOARD
DC2652A-A
VOUT0 = 1.8V
VOUT0 = 1V
70
75
80
85
90
95
100
0
20
40
60
80
100
120
EFFICIENCY (%)
LOAD CURRENT (A)
DC2652A-A F05
VOUT1 = 1.8V
VOUT1 = 1V
70
75
80
85
90
95
100
0
20
40
60
80
100
120
EFFICIENCY (%)
LOAD CURRENT (A)
DC2652A-A F06
Figure4. Demo Setup with PC
Figure5. Efficiency vs. Load Current on VOUT0 Figure6. Efficiency vs. Load Current on VOUT1

5
DEMO MANUAL DC2652A-A
Rev. 0
QUICK START PROCEDURE
VOUT0
(20MHz BW)
[50mV/DIV]
I
OUT0 0A-30A
LOAD STEP
[20A/DIV]
DC2652A-A F07
100µs/DIV
VOUT1
(20MHz BW)
[50mV/DIV]
I
OUT1 0A-30A
LOAD STEP
[20A/DIV]
DC2652A-A F08
100µs/DIV
VOUT0
(20MHz BW)
[10mV/DIV]
DC2652A-A F09
1µs/DIV
VOUT1
(20MHz BW)
[10mV/DIV]
DC2652A-A F10
1µs/DIV
Figure7. VOUT0 Load Transient Response at
VIN = 12V, VOUT0 = 1.0V
Figure9. VOUT0 Voltage Ripple at VIN = 12V,
VOUT0 = 1.0V, IOUT0 = 120A
Figure8. VOUT1 Load Transient Response at
VIN = 12V, VOUT1 = 1.0V
Figure10. VOUT1 Voltage Ripple at VIN = 12V,
VOUT1 = 1.0V, IOUT1 = 120A

6
DEMO MANUAL DC2652A-A
Rev. 0
Figure11. Thermal at VIN = 12V, VOUT0 = 1.0V, IOUT0 = 120A, VOUT1 = 1.0V, IOUT1 = 120A, TA= 23°C, No Airflow
QUICK START PROCEDURE

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DEMO MANUAL DC2652A-A
Rev. 0
LTpowerPlay is a powerful Windows based development
environment that supports Analog Devices power sys-
tem management ICs and μModules, including LTM4675,
LTM4676, LTM4677, LTM4678, LTM4680, LTM4700,
LTC3880, LTC3882, LTC3883, LTC3884 and LTC3888.
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 pres-
ent) in order to build a multichip configuration file that
can be saved and reloaded at a later time. LTpowerPlay
provides unprecedented diagnostic 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
LTPOWERPLAY SOFTWARE GUI
up rails. LTpowerPlay utilizes the DC1613A USB-to-I2C/
SMBus/PMBus controller to communicate with one of
many potential targets, including LTM4675, LTM4676,
LTM4677, LTM4678, LTM4680, LTM4700, LTC3880,
LTC3882, LTC3883, LTC3884 and LTC3888’s demo sys-
tem, or a customer board. The software also provides an
automatic update feature to keep the software current with
the latest set of device drivers and documentation. The
LTpowerPlay software can be downloaded from:
here
To access technical support documents for ADI’s
Digital Power System Management Products, visit the
LTpowerPlay Help menu.
Figure12. LTpowerPlay Main Interface

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DEMO MANUAL DC2652A-A
Rev. 0
LTPOWERPLAY QUICK START PROCEDURE
The following procedure describes how to use LTpowerPlay
to monitor and change the settings of LTC3888.
1 Download and install the LTpowerPlay GUI:
here
2. Launch the LTpowerPlay GUI.
a. The GUI should automatically identify the DC2652A-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 LTC3888 is
communicating:
c. In the Toolbar, click the “R” (RAM to PC) icon to read
theRAM fromtheLTC3888.This readstheconfiguration
from the RAM of LTC3888 and loads it into the GUI.
d. If you want to change the output voltage to a different
value, like 1.8V. In the Config tab, type in 1.8 in the
VOUT_COMMAND box, like this:
Then, click the “W” (PC to RAM) icon to write these
registervaluestotheLTC3888. After finishing this step,
you will see the output voltage will change to 1.8V.
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 whatever
you want.

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DEMO MANUAL DC2652A-A
Rev. 0
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 6 C1, C2, C3, C4, C5, C6 CAP., 270µF, ALUM, 16V, 20%, SMD 8 × 11.9mm,
E12
PANASONIC/16SVPC270M
2 18 COUT1, COUT2, COUT6, COUT7,
COUT10, COUT11, COUT14,
COUT15, COUT18, COUT19,
COUT22, COUT23, COUT26,
COUT27, COUT30, COUT31,
COUT64, COUT65
CAP., 100µF, X5R, 6.3V, 20%, 1210 AVX/12106D107MAT2A
3 32 CIN1, CIN2, CIN3, CIN4, CIN5, CIN6,
CIN7, CIN8, CIN9, CIN10, CIN11,
CIN12, CIN13, CIN14, CIN15, CIN16,
CIN17, CIN18, CIN19, CIN20, CIN21,
CIN22,CIN23, CIN24, CIN25, CIN26,
CIN27, CIN28, CIN29, CIN30, CIN31,
CIN32
CAP., 22µF, X7R, 25V, 10%, 1210 AVX/12103C226KAT2A
4 16 COUT3, COUT4, COUT8, COUT9,
COUT12, COUT13, COUT16,
COUT17, COUT20, COUT21,
COUT24, COUT25, COUT28,
COUT29, COUT32, COUT33
CAP., 470µF, TANT, POSCAP, 2.5V, 20%, 7343,
TPF Series
PANASONIC/ETPF470M5H
5 16 C7, C16, C20, C27, C29, C34, C36,
C41, C43, C48, C50, C55, C57, C62,
C64, C69
CAP., 0.47µF, X5R, 10V, 10%, 0402 AVX/0402ZD474KAT2A
6 1 C8 CAP., 4.7µF, X5R, 16V, 20%, 0603 MURATA/GRM188R61C475MAAJD
7 1 C9 CAP., 1µF, X7R, 16V, 20%, 0603 AVX/0603YC105MAT2A
8 1 C10 CAP., 2.2µF, X5R, 16V, 10%, 0603 KEMET/C0603C225K4PAC7867
9 2 C11, C108 CAP., 2.2µF, X5R, 16V, 10%, 0805 AVX/0805YD225KAT2A
10 16 C12, C14, C23, C25, C30, C32, C37,
C39, C44, C46, C51, C53, C58, C59,
C65, C67
CAP., 4.7µF, JB, 10V, 20%, 0402 TDK/C1005JB1A475M050BC
11 8 C17, C28, C35, C42, C49, C56, C63,
C70
CAP., 330pF, X7R, 50V, 10%, 0402 AVX/04025C331KAT2A
12 2 C18, C19 CAP., 3300pF, X7R, 50V, 10%, 0603 AVX/06035C332KAT2A
13 2 C21, C22 CAP., 330pF, X7R, 50V, 10%, 0603 KEMET/C0603S331K5RAC7867
14 3 CIN33, CIN34, COUT67 CAP., 10µF, X7R, 16V, 10%, 1210 AVX/1210YC106KAT2A
15 1 COUT66 CAP., 4.7µF, X5R, 16V, 20%, 1210 AVX/1210YD475MAT2A
16 2 C110, C113 CAP., 1µF, X7R, 50V, 10%, 0805 MURATA/GRM21BR71H105KA12L
17 1 C111 CAP., 4.7µF, X5R, 16V, 10%, 0603 AVX/0603YD475KAT2A
18 1 C112 CAP., 0.1µF, X7R, 16V, 10%, 0603 AVX/0603YC104KAT2A
19 1 C114 CAP., 5.6pF, C0G/NP0, 50V, ±0.25pF, 0603 AVX/06035A5R6CAT2
20 1 C116 CAP., 100pF, C0G/NP0, 25V, 5%, 0603 AVX/06033A101JAT2
21 1 D1 DIODE, SCHOTTKY, 200V, 1A, PowerDI-123,
AEC-Q101
DIODES INC./DFLS1200-7
22 8 L1, L2, L3, L4, L5, L6, L7, L8 IND., 215nH, PWR, FERRITE, 10%, 61A, 0.29mΩ,
10.4 × 8.0mm SMD
EATON/FP1007R3-R22-R
23 1 L9 IND., 4.7µH, PWR, 20%, 5.9A, 40mΩ,
5.48 × 5.28mm SMD, XAL5030, AEC-Q200
COILCRAFT/XAL5030-472ME

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DEMO MANUAL DC2652A-A
Rev. 0
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
24 1 R3 RES., 1Ω, 5%, 1/10W, 0603, AEC-Q200 VISHAY/CRCW06031R00JNEA
25 3 R9, R10, R18 RES., 1kΩ, 1%, 1/10W, 0603, AEC-Q200 NIC/NRC06F1001TRF
26 7 R15, R17, R48, R49, R51, R54, R244 RES.,10kΩ, 1%, 1/10W, 0603, AEC-Q200 KOA SPEER/RK73H1JTTD1002F
27 1 R16 RES., 4.99kΩ, 1%, 1/10W, 0603, AEC-Q200 NIC/NRC06F4991TRF
28 8 R23, R46, R68, R82, R97, R112,
R126, R139
RES., 10kΩ, 1%, 1/16W, 0402, AEC-Q200 NIC/NRC04F1002TRF
29 1 R41 RES., 18.7kΩ, 1%, 1/10W, 0603, AEC-Q200 NIC/NRC06F1872TRF
30 1 R53 RES., 2kΩ, 1%, 1/10W, 0603, AEC-Q200 KOA SPEER/RK73H1JTTD2001F
31 4 R89, R98, R234, R235 RES., 10Ω, 1%, 1/10W, 0603 NIC/NRC06F10R0TRF
32 1 R250 RES., 2Ω, 1%, 1/10W, 0603, AEC-Q200 VISHAY/CRCW06032R00FKEA
33 1 R251 RES., 100kΩ, 1%, 1/10W, 0603, AEC-Q200 PANASONIC/ERJ3EKF1003V
34 1 R252 RES., 60.4kΩ, 1%, 1/10W, 0603, AEC-Q200 PANASONIC/ERJ3EKF6042V
35 1 R253 RES., 619kΩ, 1%, 1/10W, 0603, AEC-Q200 NIC/NRC06F6193TRF
36 1 R255 RES., 200kΩ, 1%, 1/10W, 0603 NIC/NRC06F2003TRF
37 1 R256 RES., 84.5kΩ, 1%, 1/10W, 0603, AEC-Q200 NIC/NRC06F8452TRF
38 1 U1 IC, 8-Phase,Dual Output Synch. Buck Cvrtr,
QFN-52 (UHG)
LINEAR TECH/LTC3888IUHG#PBF
39 8 U2, U3, U4, U5, U6, U7, U8, U9 IC, Powerstage Gate Driver, DrMOS, PQFN 5mm ×
6mm, 70A
INFINEON/TDA21470AUMA1
40 1 U22 IC, 1A SYNC. STEP-DOWN CONVERTER, DFN-14 LINEAR TECH/LTC3646EDE-1#PBF
Additional Demo Board Circuit Components
1 0 C13, C24, C31, C38, C45, C52, C60,
C66
CAP., OPTION, 0402
2 0 C15, C26, C33, C40, C47, C54, C61,
C68,C115, C119, C121, C122
CAP., OPTION, 0603
3 0 COUT38, COUT45, COUT46,
COUT50, COUT51, COUT52,
COUT53, COUT54, COUT57,
COUT58, COUT59, COUT62
CAP., OPTION, 7343
4 4 COUT39, COUT60, COUT61,
COUT63
CAP., 470µF, TANT, POSCAP, 2.5V, 20%, 7343,
TPF Series
PANASONIC/ETPF470M5H
5 10 COUT40, COUT41, COUT42,
COUT44, COUT47, COUT48,
COUT55, COUT56, C84, C85
CAP., 100µF, X5R, 6.3V, 20%, 1210 AVX/12106D107MAT2A
6 2 COUT43, COUT49 CAP., 1µF, X7R, 16V, 20%, 0603 AVX/0603YC105MAT2A
7 4 C102, C103, C105, C106 CAP., 10µF, X5R, 10V, 10%, 0603 AVX/0603ZD106KAT2A
8 2 C104, C107 CAP., 0.01µF, C0G, 25V, 5%, 0603 AVX/06033A103JAT2
9 1 C86 CAP., 0.1µF, X7R, 50V, 10%, 0603 AVX/06035C104KAT2A
10 2 C87, C89 CAP., 1µF, X7R, 16V, 20%, 0603 AVX/0603YC105MAT2
11 1 C88 CAP., 150pF, C0G, 25V, 10%, 0603 AVX/06033A151KAT2
12 1 C90 CAP., 0.1µF, X7R, 50V, 10%, 0603 AVX/06035C104KAT2A
13 2 C91, C92 CAP., 0.01µF, C0G, 25V, 5%, 0603 AVX/06033A103JAT2A
14 6 C99, C100, C101, C117, C118, C120 CAP., 0.1µF, X7R, 50V, 10%, 0603 AVX/06035C104KAT2A
15 0 D2, D3 DIODE, OPTION, SOD-323