LINEAR TECHNOLOGY DC2088A DC Converter with Power System Management Instruction Manual
- June 11, 2024
- LINEAR TECHNOLOGY
Table of Contents
DEMO MANUAL DC2088A
High Density LTC3880
Step-Down DC/DC Converter with
Power System Management
DESCRIPTION
Demonstration circuit 2088A is a high current, high density, two-phase single
output synchronous buck converter featuring the LTC3880EUJ, a dual-phase
current mode controller. The LT C ® 3880 has the PMBus interface and power
system management functions.
The layout of DC2088A is very compact and the total solution is within a 1.0″
× 1.0″ area. The DrMOS is used on the board for high current, high efficiency.
The input range of this board is from 7V to 14V, and the output voltage can be
programmed from 0.8V to 1.8V, with an output current up to 50A. The factory
default setting for the output is 1.0V. The DC2088A also has an on-board
dynamic load circuit, which makes it easy for the customer to evaluate the
transient performances.
The DC2088A powers up to default settings and produces power based on
configuration resistors or NVM without the need for any serial bus
communication. This allows easy evaluation of the DC/DC converter aspects of
the LTC3880. To fully explore the extensive power system management features
of the parts, download the GUI software LTpowerPlay onto your PC and use LT C
’s I2 C/ 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:
www.linear.com/ltpowerplay
For more details and instructions on LTpowerPlay, please refer to “LTpowerPlay
for LTC3880 Quick Start Guide”.
Design files for this circuit board are available at
http://www.linear.com/demo
, LT, LTC, LTM, Linear Technology and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
PERFORMANCE SUMMARY
Specifications are at TA = 25°C
SYMBOL| PARAMETER| CONDITIONS| MIN| TYP| MAX|
UNITS
---|---|---|---|---|---|---
VIN| Input Supply Range| | 7| 12| 14| V
VOUT| Output Voltage Range| IOUT = 0A TO 50A, VIN = 7.0V to 14V| 0.8| 1.0|
1.8| V
IOUT| Output Current Range| | 0| | 50| A
fSW| Factory Default Switching| | 425| kHz
EFF| Peak Efficiency| VOUT = 1.0V, See Figures 4.| 87.8| %
Quick start proceDure
Demonstration circuit 2088A makes it easy to set up to evaluate the
performances of the LTC3880. 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 C14. See Figure 3 for proper scope
probe technique.
-
Make sure jumpers are in the following positions:
JUMPER| POSITION| FUNCTION
---|---|---
JP1| ON| Drives ON
JP2| OFF| LED -
With power off, connect the input power supply to VIN and GND. Connect active load to the output.
-
Make sure RUN switch (SW) is OFF.
-
Turn on the power at the input.
NOTE. Make sure that the input voltage does not exceed 16V. -
Turn on RUN switch as desired.
-
Check for the correct output voltage from E4 to E6.
VOUT = 1.0V ± 0.5% (1.005V ~ 0.995V)
NOTE. If there is no output, temporarily disconnect the load to make sure that the load is not set too high. -
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.
-
Connect the dongle and control the output voltages from the GUI. See “LTpowerPlay QUICK START” session for details.
CONNECTING A PC TO DC2088A
You can use a PC to reconfigure the power management features of the LTC3880
such as: nominal VOUT, margin set points, 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. The Dongle can be hot plugged.
MEASURING EFFICIENCY (SEE FIGURE 2)
- To accurately measure efficiency of any configuration, do the following:
- Set JP1, JP2 to OFF position to disable all the auxiliary circuits.
- Make sure R4, R10 not stuffed.
- Provide an external 5V for the gate drive, and connect it to E15 and E16.
- Measure VIN across the input ceramic capacitor (C29). Measure VOUT across the output ceramic capacitor (C14). Add the driver loss (VDR • IDR) to the total ef-ficiency calculation.
EVALUATING THE LTC3880-1
For applications that require the highest possible efficiency, the LTC3880-1
allows the user to supply the bias voltage and gate driver current from an
external power supply.
Please install R4 (0Ω). Then, the 5V gate drive for the DrMOS will also
provide power to the EXTVCC. To accurately measure efficiency of a demo board
containing the
LTC3880-1,
- Set JP1, JP2 to OFF to disable the LDO.
- Connect an external 5V power supply to E15, E16.
- Measure VIN across the input ceramic capacitor (C29).
Measure VOUT across the output ceramic capacitor (C14).
MEASURING OUTPUT RIPPLE VOLTAGE
An accurate ripple measurement may be performed by using the below
configuration across C16.
LTpowerPlay Software GUI
LTpowerPlay is a powerful Windows based development environment that supports
Linear Technology power system management ICs, including the 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 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 up rails. LTpowerPlay utilizes the
DC1613A USB-to-SMBus controller to communicate with one of many potential
targets, including the LTC3880’s DC2088A demo system, 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:
www.linear.com/ltpowerplay
To access technical support documents for LT C Digital Power Products visit
Help. View online help on the LTpowerPlay menu.
LTpowerPlay QUICK START PROCEDURE
The following procedure describes how to use LTpowerPlay to monitor and change
the settings of LTC3880.
- Download and install the LTPowerPlay GUI: http://linear.com/ltpowerplay
- Launch the LTpowerPlay GUI. a. The GUI should automatically identify the DC2088A. 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 LTC3880 and the LTC3883 are communicating:
c. In the Toolbar, click the “R” (RAM to PC) icon to read the RAM from the
LTC3880 and the LTC3883This reads the configuration from the RAM of LTC3883
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 register values to the
LTC3880 and the LTC3883. 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 whatever you want.
PARTS LIST
ITEM| QTY| REFERENCE| PART DESCRIPTION|
MANUFACTURER/PART NUMBER
---|---|---|---|---
Required Circuit Components
| 1 | 4 | C1, C2, C28, C29 | CAP., X5R, 22µF, 25V, 10%,1210 | AVX, 12103D226KAT |
|---|---|---|---|---|
| 2 | 2 | C5, C30 | CAP., X5R, 1µF, 10V, 20%, 0603 | AVX, 0603ZD105MAT2A |
| 3 | 6 | C4, C10, C11, C16, C27, C36 | CAP., X5R, 1µF, 10V, 20%, 0402 | AVX, |
0402ZD105MAT2A
4| 1| C6| CAP., X5R, 10µF, 10V, 20%, 0603| SAMSUNG, CL10A106MP8NNNC
5| 3| C3, C9, C26| CAP., X7R, 0.1µF, 25V, 10%, 0603| AVX, 06033C104KAT
6| 2| C7, C8| CAP., OS-CON, 330µF, 16V, 20%| SANYO, 16SVP330M
7| 20| C12-C15, C17, C31-C35, C43-C52| CAP., X5R, 100µF, 6.3V, 20%,1206| TAYO
YUDEN, JMK316BJ107ML-T
8| 2| C18, C19| CAP., POSCAP, 470µF, 2.5V, D2E| SANYO 2R5TPE470M9
9| 2| C22, C37| CAP., X5R, 0.22µF, 16V, 20%, 0402| TDK, C1005X5R1C224M
10| 1| C23| CAP., X7R, 1nF, 25V, 10%, 0402| AVX, 04023C102KAT2A
11| 1| C24| CAP., NPO, 100pF,25V, 10%, 0402| AVX,04023A101KAT2A
12| 1| C25| CAP., X5R, 10nF, 25V, 10%, 0402| AVX, 04023D103KAT2A
13| 2| L1, L2| INDUCTOR, SMT POWER IND. 0.16µH| COILCRAFT., XAL7070-161ME
14| 1| Q1| TRANS GP SS PNP 40V SOT-23| ON SEMI MMBT3906LT1G
15| 1| Q3| MOSFET P-CH 20V, 0.58A, SOT-23| VISHAY, TP0101K-T1-E3
16| 6| R2, R11, R12, R16, R17, R30| RES., CHIP, 0, 1%, 0402| VISHAY,
CRCW04020000Z0ED
17| 4| R1, R13, R36, R66| RES., CHIP, 0, 1%, 0603| VISHAY, CRCW06030000Z0EA
18| 2| R3, R15| RES., CHIP, 10, 1%, 0603| VISHAY, CRCW060310R0FKEA
19| 2| R7, R19| RES., CHIP, 10k, 1%, 0402| VISHAY, CRCW040210K0FKED
20| 5| R18, R20, R22, R24, R39| RES., CHIP, 10k, 1%, 0603| VISHAY,
CRCW060310K0FKEA
21| 1| R6| RES., CHIP, 1, 1%, 0402| VISHAY, CRCW04021R00FKED
22| 4| R8, R9, R25, R27| RES., CHIP, 825, 1%, 0402| VISHAY, CRCW0402825RJNED
23| 1| R14| RES., CHIP, 6.81k, 1%, 0402| VISHAY, CRCW04026K81FKED
24| 1| R23| RES., CHIP, 20k, 1%, 0402| VISHAY,CRCW040220K0FKED
25| 1| R28| RES., CHIP, 17.8k, 1%, 0402| VISHAY,CRCW040217K8FKED
26| 1| R31| RES., CHIP, 16.2k, 1%, 0603| VISHAY, CRCW060316K2FKEA
27| 1| R33| RES., CHIP, 24.9k, 1%, 0603| VISHAY, CRCW060324K9FKEA
28| 1| R34| RES., CHIP, 4.32k, 1%, 0603| VISHAY, CRCW06034K32FKEA
29| 1| R40| RES., CHIP, 15.8k, 1%, 0603| VISHAY, CRCW060315K8FKEA
30| 2| U1, U3| IC, HIGH FREQUENCY DrMOS MOUDLE| FAIRCHILD, FDMF6823A
31| 1| U2| IC, LTC3880EUJ, QFN 6mm ´ 6mm| LTC., LTC3880EUJ#PBF
Additional Circuit Components
| 1 | 2 | CBYP1, CBYP2 | CAP., X7R, 0.01µF,16V, 10%, 0603 | AVX, 0603YC103KAT |
|---|---|---|---|---|
| 2 | 2 | COUT1, COUT2 | CAP., X5R, 10µF,25V, 20%,1206 | TDK, C3216X7R1E106M |
| 3 | 1 | C40 | CAP., X7R, 1µF, 16V, 10%, 1206 | AVX, 1206YC105KAT |
| 4 | 1 | C41 | CAP., X7R, 0.1µF, 25V, 10%, 0603 | AVX, 06033C104KAT |
| 5 | 1 | C39 | CAP., X5R, 1µF, 16V, 20%, 0805 | AVX, 0805YD105MAT |
| 6 | 0 | C20, C21, C53, C54 | CAP., POSCAP, 470µF, 2.5V, D2E | SANYO 2R5TPE470M9 |
| 7 | 1 | C38 | CAP., X5R, 2.2µF, 16V, 10%, 0805 | AVX, 0805YD225KAT |
| 8 | 1 | C42 | CAP., X5R, 10nF, 25V, 10%, 0603 | AVX, 06033D103KAT |
| 9 | 1 | C55 | CAP., X7R, 0.1µF,16V, 10%, 0603 | AVX, 0603YC104KAT |
| ITEM | QTY | REFERENCE | PART DESCRIPTION |
MANUFACTURER/PART NUMBER
---|---|---|---|---
10| 1| D1| LED GREEN S-GW TYPE SMD| ROHM, SML-010FTT86L
11| 1| D2| LED RED S-TYPE GULL WING SMD| ROHM, SML-010VTT86L
12| 1| D3| DIODE, SCHOTTKY, SOD-323| CENTRAL CMDSH-3TR
13| 1| Q2| MOSFET SPEED SRS 30V 30A LFPAK| RENESAS, RJK0305DPB-00#J0
14| 1| Q3| MOSFET P-CH 20V 0.58A SOT-23| VISHAY, TP0101K-T1-E3
15| 1| Q5| MOSFET N-CH 60V 115MA SOT-23| FAIRCHILD, 2N7002A-7-F
16| 7| R54-R60| RES., CHIP, 0, 1%, 0603| VISHAY, CRCW06030000Z0EA
17| 1| R51| RES., CHIP, 10, 1%, 0603| VISHAY, CRCW060310R0FKEA
18| 2| R38, R48| RES., CHIP, 10k, 1%, 0603| VISHAY, CRCW060310K0FKEA
19| 2| R43, R44,| RES., CHIP, 100k, 1%, 0603| VISHAY, CRCW0603100KFKEA
20| 1| R10| RES., CHIP, 30, 1%, 2512| VISHAY, CRCW251230R0FKEA
21| 0| R21, R62, R63 (OPT)| RES., 0402|
22| 0| R4, R5, R26, R29, R32, R35 (OPT)| RES., 0603|
23| 0| R47 (OPT)| RES., 0805|
24| 1| R37| RES., CHIP, 200, 1%, 0603| VISHAY, CRCW0603200RFKEA
25| 1| R41| RESISTOR .010Ω 1W, 1% 2512| PANASONIC, ERJ-M1WSF10MU
26| 1| R42| RES., CHIP, 127, 1%, 0603| VISHAY, CRCW0603127RFKEA
27| 2| R45, R46| RES., CHIP, 4.99k, 1%, 0603| VISHAY, CRCW06034K99FKEA
28| 1| R49| RES., CHIP, 6.19k, 1%, 0603| VISHAY, CRCW06036K19FKEA
29| 1| R50| RES., CHIP, 3.4k, 1%, 0603| VISHAY, CRCW06033K40FKEA
30| 2| R52, R53| RES., CHIP, 2k, 1%, 0603| VISHAY, CRCW06032K00FKEA
31| 1| U4| IC, SERIAL EEPROM| MICROCHIP 24LC025-I/ST
32| 1| U5| IC, LT3029IMSE, MSOP, 16 PIN| LTC., LT3029IMSE#PBF
Hardware
1| 8| E1, E2, E4, E6, E11, E12, E15, E16| TESTPOINT, TURRET, .062″| MILL-MAX,
2308-2-00-80-00-00-07-0
---|---|---|---|---
2| 2| J1, J2| JACK, BANANA| KEYSTONE 575-4
3| 2| J3, J4| STUD, TEST PIN| PEM KFH-032-10
4| 4| J3, J4(X2)| NUT, BRASS 10-32| ANY #10-32
5| 2| J3, J4| RING, LUG #10| KEYSTONE, 8205, #10
6| 2| J3, J4| WASHER, TIN PLATED BRASS| ANY #10
7| 2| J5, J7| CONN, BNC, 5-PINS| CONNEX, 112404
8| 1| J6| CONN HEADER 12POS 2mm STR DL PCB| FCI 98414-G06-12ULF
9| 1| J8| HEADER., DOUBLE ROW, RIGHT ANGLE 2 ´ 5 PIN| MILL-MAX
802-40-010-20-001000
10| 1| J9| SOCKET, DOUBLE ROW, 2 ´ 5 PIN| MILL-MAX 803-43-010-20-001000
11| 2| JP1, JP2| HEADER 3 PIN 0.079 SINGLE ROW| SULLIN, NRPN031PAEN-RC
12| 2| JP1, JP2| SHUNT| SAMTEC, 2SN-BK-G
13| 1| SW| SWITCH SLIDE 1PDT 6VDC 0.3A SMT| C & K JS102011SAQN
14| 4| STANDOFF| STANDOFF, SNAP ON| KEYSTONE_8831
15| 1| STENCIL| STENCIL|
SCHEMATIC DIAGRAM
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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LT C ) 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 LT
C 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 FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF
THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT,
SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES. The user assumes all
responsibility and liability for proper and safe handling of the goods.
Further, the user releases LT C from all claims arising from the handling or
use of the goods. Due to the open construction of the product, it is the
user’s responsibility to take any and all appropriate precautions with regard
to electrostatic discharge. Also be aware that the products herein may not be
regulatory compliant or agency certified (FCC, UL, CE, etc.). No License is
granted under any patent right or other intellectual property whatsoever. LT C
assumes no liability for applications assistance, customer product design,
software performance, or infringement of patents or any other intellectual
property rights of any kind. LT C currently services a variety of customers
for products around the world, and therefore this transaction is not
exclusive. Please read the DEMO BOARD manual prior to handling the product.
Persons handling this product must have electronics training and observe good
laboratory practice standards. Common sense is encouraged. This notice
contains important safety information about temperatures and voltages. For
further safety concerns, please contact a LT C application engineer.
Mailing Address:
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1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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