Linear Technology DC1936A Quick setup guide

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DEMO MANUAL DC1936A
DESCRIPTION
LTC3882EUJ
Dual Output Step-Down DC/DC Controller
with Power System Management
Demonstration circuit 1936A is a high current, high ef-
ficiency, polyphase synchronous buck converter featuring
the LTC3882EUJ, a dual output polyphase voltage mode
controller. The LTC3882 has the PMBus interface and
power system management functions.
The DC1936A uses 6mm × 6mm DrMOS as the power
stage. The input range of this board is from 7V to 14V,
and the output voltage can be programmed from 0.8V to
1.8V.TheDC1936Aprovides two outputs, with each output
capable of 1V/30A. The DC1936A has optional discrete
driver (LTC4449EDCB) and MOSFET footprints for high
input voltage applications up to 38V. The DC1936A also
has an on-board dynamic load circuit, which makes it easy
for the customer to evaluate the transient performances.
The DC1936A powers up to default settings and pro-
duces power based on configuration resistors or with its
non-volatile memory without the need for any serial bus
communication. This allows easy evaluation of the DC/
DC converter. To fully explore the extensive power system 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.
PERFORMANCE SUMMARY
management features of the parts, download the GUI
software LTpowerPlay™ onto your PC and use LT C ’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 settings within its onboard
EEPROM, along with viewing telemetry parameters that
include 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 for LTC3880 Quick Start Guide. The
LTC3882 operation in LTpowerPlay is similar to that of
the LTC3880.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1936A
Specifications are at TA= 25°C
*Note: The DC1936A uses 4V-rated low ESR PosCAP (Part No. 4TPF470ML) as output capacitors for optimized load transient performance. If >3.6V VOUT
is needed, 6.3V-rated output capacitors should be used.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIN Input Supply Range 7 12 14 V
VOUT0,1 Output Voltage Range IOUT = 0A TO 30A, VIN = 7V to 14V 0.8 1 1.8* V
IOUT0,1 Output Current Range 0 30 A
fSW Factory Default Switching 500 kHz
EFF Peak Efficiency VIN = 12V, VOUT0 = 1V, See Figure 4 90.4 %
LOAD TRANSIENT Output Voltage Peak-to-Peak Spike During
Load Transient
VIN = 12V, VOUT0 = 1V, ISTEP = 0A – 7.5A 30 mV
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DEMO MANUAL DC1936A
QUICK START PROCEDURE
Demonstration circuit 1936A makes it easy to set up
to evaluate the performances of the LTC3882. Refer to
Figure 2 for proper measurement equipment setup and
follow the procedure below:
NOTE: When measuring the input or output voltage ripple,
care must be taken to avoid a long ground lead on the
oscilloscope probe. Measure the output voltage ripple by
touching the probe tip directly across the C10/C45. See
Figure 3 for proper scope probe technique.
1. Make sure jumpers are in the following positions:
JUMPER POSITION FUNCTION
JP1 C GPIO0B to GPIO1B
JP2 NC RUN0 to RUN1
JP3 ON 5V Bias for DrMOS
JP4 ON Bias Supply for VCC of the LTC3882
JP5 OFF Write Protection
2. With power off, connect the input power supply to VIN
and GND. Connect active load to the output.
3. Make sure RUN switch (SW3 and SW4) is OFF.
4. Turn on the power at the input.
NOTE. Make sure that the input voltage does not
exceed 16V.
5. Turn on RUN switch as desired.
6. Check for the correct output voltage from E6 to E7 for
CH0 and from E8 to E9 for CH1. VOUT = 1V± 0.5%
(0.995V ~ 1.005V)
NOTE: If there is no output, temporarily disconnect the
load to make sure that the load is not set too high.
7. Once the proper output voltage is established, adjust
the loads within the operating range and observe the
output voltage regulation, ripple voltage, efficiency and
other parameters.
8. Connect the dongle and control the output voltages
from the GUI. See LTpowerPlay QUICK START session
for details.
Connecting a PC to DC1936A
You can use a PC to reconfigure the power management
features of the LTC3882 such as: nominal VOUT, margin
setpoints, OV/UV limits, temperature fault limits,sequenc-
ing parameters, the fault log, fault responses, GPIO and
other functionality. The DC1613A dongle may be plugged
in regardless of whether or not VIN is present. Dongle can
be hot-plugged.
Figure 1. Demo Setup with PC
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DEMO MANUAL DC1936A
QUICK START PROCEDURE
Figure 2. Power Test Setup for DC1936A
Measuring Efficiency for DC1936A (See Figure 2)
To accurately measure efficiency of any configuration, do
the following:
nSet JP3 and JP4 to OFF position to disable the auxiliary
circuits.
nTurn on one channel only.
nApply external 5V from E21 to E22 as the driver supply
for DrMOS.
nApply external 5V from E5 to E29 as VCC for LTC3882.
nMeasure VIN across the input ceramic capacitor (C6 for
CH1, C39 for CH0). Measure VOUT across the output
ceramic capacitor (C45 for CH1, C10 for CH0).
nThe efficiency is calculated as:
Efficiency =
V
OUT
•I
OUT
V
IN
•I
IN
+V
DR
•I
DR
+V
CC
•I
CC
•100%
Measuring Output Ripple Voltage
An accurate ripple measurement may be performed by
using the configuration across C10 as shown in Figure 3.
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DEMO MANUAL DC1936A
QUICK START PROCEDURE
Figure 4. Typical Efficiency Curves of DC1936A, VIN = 12V, fSW = 500kHz, Single Phase
Figure 3. Measuring Output Voltage Ripple
+ –
VOUT GND
COUT
LOAD CURRENT (A)
0
EFFICIENCY (%)
92
90
88
86
84
82
91
89
87
85
83
81
80 2010 30
dc1936a F04
35
155 25
12VIN, 1VOUT, 500kHz
12VIN, 1.2VOUT, 500kHz
12VIN, 0.9VOUT, 500kHz
12VIN, 0.8VOUT, 500kHz
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DEMO MANUAL DC1936A
QUICK START PROCEDURE
Figure 5. Load Transient Waveform of DC1936A, VIN = 12V, VOUT0 = 1V, fSW = 500kHz, 0% to 25% Load Step
Figure 6. Thermal Picture of DC1936A, VIN = 12V, VOUT0 = VOUT1 = 1V, IOUT0 = IOUT1 = 30A, fSW = 500kHz, No Airflow, TA= 25°C
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DEMO MANUAL DC1936A
LTpowerPlay SOFTWARE GUI
LTpowerPlay is a powerful Windows based development
environment that supports Linear Technology power sys-
tem management ICs, including the LTC3880, LTC3883,
LTC3882, 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.LTpowerPlayprovidesunprecedenteddiagnostic
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 LTC3882’s
DC1936A demo system, or a customer board. The soft-
ware 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: http://linear.com/ltpowerplay
To access technical support documents for LT C Digital
Power Products visit Help. View online help on the
LTpowerPlay menu.
Figure 7. LTpowerPlay Main Interface
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DEMO MANUAL DC1936A
LTpowerPlay QUICK START PROCEDURE
ThefollowingproceduredescribeshowtouseLTpowerPlay
to monitor and change the settings of LTC3882.
1. Download and install the LTPowerPlay GUI:
http://linear.com/ltpowerplay
2. Launch the LTpowerPlay GUI.
a. The GUI should automatically identify the DC1936A.
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 the LTC3882
is communicating:
c. In the Toolbar, click the R (RAM to PC) icon to read the
RAM from the LTC3882. This reads the configuration
from the RAM of LTC3882 and loads it into the GUI.
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:
Then, click the W (PC to RAM) icon to write these reg-
ister values to the LTC3882. After finishing this step,
you will see the output voltage will change to 1.5V.
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DEMO MANUAL DC1936A
LTpowerPlay QUICK START PROCEDURE
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.
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 4 C6, C7, C39, C40 CAP., X5R 22µF 25V 10% 1210 AVX, 12103D226KAT2A
2 5 C1, C3, C17, C33, C37 CAP., X7R 1µF 16V 10% 0603 AVX, 0603YC105KAT2A
3 2 C25, C32 CAP., X7R 3.3nF 25V 10% 0603 AVX, 06033C332KAT2A
4 2 C26, C31 CAP., X7R 330pF 16V 0603 AVX, 0603YC331KAT2A
5 1 C59 CAP., X7R 1µF 16V 10% 1206 AVX, 1206YC105KAT2A
6 3 C2, C16, C34 CAP., X5R 2.2µF 16V 10% 0603 TDK, C1608X5R1C225K
7 2 C27, C30 CAP., NPO 33pF 50V 5% 0603 AVX, 06035A330JAT2A
8 2 C4, C5 CAP., OS-CON, 330µF, 16V, 20%, F12 PANASONIC, 16SVP330M
9 3 C8, C54, C67 CAP., X7R 0.1µF 50V 10% 0603 AVX, 06035C104KAT2A
10 8 C9-C12, C45-C48 CAP., X5R 100µF 6.3V 1210 AVX, 12106D107MAT2A
11 6 C14, C15, C23, C41, C49, C50 CAP., POSCAP, 470µF, 4V, D3L SIZE PANASONIC, 4TPF470ML
12 1 C18 CAP., X5R 4.7µF 25V 0805 TAIYO YUDEN, TMK212ABJ475KG-T
13 2 C24, C66 CAP., X7R 0.22µF 25V 10% 0603 TDK, C1608X7R1E224K
14 2 C61, C62 CAP., X7R 2.2µF 6.3V 10% 0805 MURATA, GRM21BR70J225KA01L
15 6 C28, C29, C38, C51, C64, C65 CAP., X7R 0.01µF 50V 10% 0603 AVX, 06035C103KAT2A
16 2 L1, L2 INDUCTOR, SMT POWER IND. 0.22µH PULSE, PA0515.221N LT
17 2 Q1, Q2 TRANS GP SS PNP 40V SOT-23 ON SEMI., MMBT3906LT1G
18 13 R1, R21, R26-R28, R43, R44, R48,
R49, R64, R68, R105, R45
RES., CHIP 0Ω, 0603 VISHAY, CRCW06030000Z0EA
19 4 R3, R51, R69, R104 RES., CHIP, 10Ω, 5%, 0603 VISHAY, CRCW060310R0JKEA
20 1 R31 RES., CHIP, 17.4k, 1%, 0603 VISHAY, CRCW060317K4FKEA
21 1 R32 RES., CHIP, 16.2k, 1%, 0603 VISHAY, CRCW060316K2FKEA
22 2 R29, R36 RES., CHIP, 357Ω, 1%, 0603 VISHAY, CRCW0603357RFKEA
23 2 R5, R54 RES., CHIP, 1Ω, 1%, 0603 NIC, NRC06F1R00TRF
24 2 R30, R33, R6, R13-R18, R56, R61,
R72, R73, R86, R87, R88, R89
RES., CHIP, 10k, 5%, 0603 VISHAY, CRCW060310K0JKEA
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DEMO MANUAL DC1936A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
25 2 U1, U3 IC, HIGH FREQUENCY DrMOS MOUDLE FAIRCHILD, FDMF6820A
26 1 U2 IC, LTC3882EUJ, QFN 6mm x 6mm LINEAR TECH., LTC3882EUJ#10BJ-2PBF-ES
27 1 U4 IC, 24LC025-I/ST, SOIC MICROCHIP, 24LC025-I/ST
Additional Demo Board Circuit Components
1 0 CIN1, CIN2, CIN3, CIN4 OPT CAP., X5R 22µF 25V 10% 1210 AVX, 12103D226KAT2A
2 2 C35, C36 OPT CAP., X7R 47pF 5% 50V 0603 OPT
3 2 C60, C63 CAP., X5R 10µF 35V 1206 TAIYO YUDEN, GMK316BJ106ML-T
4 0 C55, C56, C57, C58, C19, C20, C21,
C42, C43, C44 OPT
CAP., 0603
5 0 D1, D2 OPT DIODE, SCHOTTKY, SOD-323
6 1 D6 DIODE, SCHOTTKY, SOD-323 CENTRAL SEMI., CMDSH-3TR
7 2 D3, D4 LED, 0603 GREEN WURTH ELEKTRONIK, 150060GS75000
8 1 D5 LED, 0603 RED WURTH ELEKTRONIK, 150060SS75000
9 0 D7, D8 DIODE, SOD-323
10 2 Q11, Q12 MOSFET SPEED SRS 30V 30A LFPAK RENESAS, RJK0305DPB-00#J0
11 0 Q3, Q4, Q5, Q6 OPT MOSFET SPEED SRS 30V 30A LFPAK RENESAS, RJK0305DPB-00#J0
12 0 Q7, Q8, Q9, Q10 OPT MOSFET JET SERIES 30V 45A LFPAK RENESAS, RJK0330DPB-00#J0
13 2 Q13, Q14 MOSFET P-CH 20V 0.58A SOT-23 VISHAY, TP0101K-T1-E3
14 2 Q15, Q16 MOSFET N-CH 60V 115MA SOT-23 FAIRCHILD, 2N7002
15 2 SW1, SW2 CONNECTOR, SUB MINIATURE SLIDE SWITCHES C&K., JS202011CQN
16 0 R34, R35, R37-R42, R82-R85, R101,
R102, R46, R47, R58, R59, R60, R66,
R71, R98, R65, R70, R76, R77, R67,
R103, R107 OPT
RES., CHIP, 0603
17 2 R8, R55 RES., CHIP, 1.21k, 1%, 0603 VISHAY, CRCW06031K21FKEA
18 2 R12, R63 RES., CHIP, 30Ω, 1%, 2512 VISHAY, CRCW251230R0FKEG
19 1 R62 RES., CHIP, 15.8k, 1%, 0603 VISHAY, CRCW060315K8FKEA
20 4 R79, R80, R19, R20 RES., CHIP, 4.99k, 1%, 0603 NIC, NRC06F4991TRF
21 2 R90, R91 RES., CHIP, 6.19k, 1%, 0603 VISHAY, CRCW06036K19FKEA
22 2 R92, R93 RES., CHIP, 0.01Ω, 1%, 2010 VISHAY WSL2010R0100FEA
23 4 R94, R95, R4, R52 RES., CHIP, 2k, 1%, 0603 VISHAY, CRCW06032K00FKEA
24 2 R96, R97 RES., CHIP, 200Ω, 1%, 0603 VISHAY, CRCW0603200RFKEA
25 2 R57, R99 RES., CHIP, 50Ω, 1%, 0603 VISHAY, CRCW060350R0FKEA
26 1 R100 RES., CHIP, 127Ω, 1%, 0603 VISHAY, CRCW0603127RFKEA
27 0 U5, U6 OPT N-CHANNEL MOSFET DRIVER, LTC4449IDCB
28 1 U7 IC, LT3029IMSE, MSOP, 16 PIN LINEAR TECH., LT3029IMSE#PBF
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DEMO MANUAL DC1936A
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Hardware: For Demo Board Only
1 29 E1-E29 TESTPOINT, TURRET, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0
2 2 J1, J2 JACK, BANANA KEYSTONE, 575-4
3 4 J3-J6 STUD, TEST PIN PEM KFH-032-10
4 8 J3-J6 (X2) NUT, BRASS 10-32 ANY #10-32
5 4 J3-J6 RING, LUG #10 KEYSTONE, 8205, #10
6 4 J3-J6 WASHER, TIN PLATED BRASS ANY #10
7 1 J14 CONN RECEPT 2MM DUAL R/A 14POS (F) SULLINS, NPPN072FJFN-RC
8 1 J15 HEADER 14POS 2MM R/A GOLD (M) MOLEX, 87760-1416
9 1 J10 CONN HEADER 12POS 2MM STR DL PCB FCI 98414-G06-12ULF
10 5 JP1-JP5 0.079 SINGLE ROW HEADER, 3 PIN SULLIN, NRPN031PAEN-RC
11 5 JP1-JP5 SHUNT SAMTEC, 2SN-BK-G
12 2 J11, J12 CONN, BNC, 5 PINS CONNEX, 112404
13 2 SW1, SW2 CONNECTOR, SUB MINIATURE SLIDE SWITCHES C&K., JS202011CQN
PARTS LIST
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