DC2028A - Demo Manual

DEMO MANUAL DC2028A
8-Channel Power Supply
System Featuring the LTC2977
PMBus Power System Manager
Description
The DC2028A is a demonstration system that showcases
the LTC®2977, an 8-channel I2C/SMBus/PMBus Power
System Manager with EEPROM. The LTC2977 monitors
and controls eight power supply rails. The DC2028A
demonstrates the ability of the LTC2977 to sequence, trim,
margin, supervise, monitor, and log faults for eight power
supplies. Each power supply channel’s output voltage is
monitored and the LTC2977 monitors its own internal die
temperature.
The DC2028A is a single circuit board that contains eight
independent power supply rails. The board employs eight
LTC3405A 300mA switch mode regulators, which are
configured to be controlled by the LTC2977. The DC2028A
demo board provides a sophisticated 8-channel digitally
programmable power supply system. The rail voltages
are programmable within the trim range shown in Table 1.
This demonstration system is supported by the
LTpowerPlay™ graphical user interface (GUI) which enables
complete control of all the features of the device. Together,
the LTpowerPlay software and DC2028A hardware system
create a powerful development environment for designing
and testing configuration settings of the LTC2977. These
settings can be stored in the device’s internal EEPROM or
in a file. This file can later be used to order preprogrammed
devices or to program devices in a production environment.
The software displays all of the configuration settings and
real time measurements from the Power System Management IC. Telemetry allows easy access and decoding of
the fault log created by the LTC2977. The board comes
preprogrammed with the EEPROM values appropriate for
the eight power supply rails on the DC2028A. Just plug
and play!
Multiple DC2028A boards can be cascaded together to
form a high channel count power supply (see Multi-Board
Arrays). This cascaded configuration demonstrates features of the LTC Power System Management ICs which
enable timing and fault information to be shared across
multiple Power System Management ICs. The user can
configure up to eight DC2028A boards, thereby controlling
up to 64 separate power supply rails. Larger board arrays
can be built using programmable I2C base addresses or
bus segmentation.
The DC2028A demo board can be powered by an external
power supply, such as a 12VDC supply. Communication
with the software is provided through the DC1613 USB-toI2C/SMBus/PMBus controller. The following is a checklist
of items which can be obtained from the LTC website or
LTC Field Sales.
• USB-to-I2C/SMBus/PMBus Controller (DC1613)
• LTpowerPlay Software
Design files for this circuit board are available at
http://www.linear.com/demo
DC2028A Features
Sequence, Trim, Margin, and Supervise Eight Power
Supplies
n
Manage Faults, Monitor Telemetry, and Create Fault
Logs
n
PMBus Compliant Command Set
n
Supported by LTpowerPlay GUI
n
Margin or Trim Supplies to 0.25% Accuracy
n
Fast OV/UV Supervisors per Channel
n
Supports Multichannel Fault Management
n
Automatic Fault Logging to Internal EEPROM
n
Operates Autonomously without Additional SW
n
Eight OV/UV VOUT and One VIN Supervisor
n
Telemetry Reads Back VIN, VOUT, and Temperature
n
8-Channel Time-Based Output Sequencer
n
I2C/SMBus Serial Interface
n
Powered from 6V to 14V
n
LTC2977 Available in 64-Lead QFN Package
n
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. Protected by U.S. Patents including 7382303, 7420359 and
7940091.
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DEMO MANUAL DC2028A
Performance Summary
Specifications are at TA = 25°C
POWER SUPPLY CHANNEL
CH(0:7)
Manager/Controller
LTC2977
Nominal Untrimmed Output Voltages
1.2V, 1.5V, 1.8V, 2.0V,
2.5V, 2.7V, 3.0V, 3.3V
Rated Output Current
0.3A
Default Margin Range
±5%
Output Trim Range (VFS_VDAC = 1.38V)
+15%/–11%
Temperature
1 Internal
Common Characteristics PARAMETER
Specifications Valid Over Full Operating Temperature Range
CONDITIONS
MIN
Supply Input Voltage Range
6
ADC Total Unadjusted Error
VIN_ADC ≥ 1V
ADC Voltage Sensing Input Range
Differential Voltage: VIN_ADC = (VSENSEP[n] – VSENSEM[n])
0
TYP
MAX
UNITS
14
V
±0.25
%
6
V
GLOSSARY OF TERMS
The following list contain terms used throughout the
document.
Channel – The collection of functions that monitor, supervise, and trim a given power supply rail.
EEPROM – Non-volatile memory (NVM) storage used to
retain data after power is removed.
Margin – Term used typically in board level testing that
increases/decreases the output voltage to look for sensitivity/marginality problems.
Monitor – The act of measuring voltage, current, and
temperature readings.
PMBus – An industry standard power management protocol with a fully defined command language that facilitates
communication with power converters and other devices
in a power system.
Rail – The final output voltage that the power supply
controller manages.
Supervise – The act of quickly responding to a voltage,
current, temperature condition that is compared to preprogrammed values (fault settings).
Trim – The act of adjusting the final output voltage. A servo
loop is typically used to trim the voltage.
NVM – Non-volatile memory, see EEPROM.
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DEMO MANUAL DC2028A
LTpowerPlay GUI SOFTWARE
LTpowerPlay is a powerful Windows based development
environment that supports Linear Technology power
system management ICs with EEPROM, including the
LTC2977 8-channel PMBus Power System Manager. 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 multi-chip configuration file that can be
saved and reloaded at a later time. LTpowerPlay provides
unprecedented system level 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 DC1613 I2C/SMBus/
PMBus controller to communicate with one of many potential targets, including the DC2028A 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:
http://www.linear.com/ltpowerplay
To access technical support documents for LTC Power
System Management Products visit Help, View Online
Help on the LTpowerPlay menu.
Figure 1. Screenshot of the LTpowerPlay GUI
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DEMO MANUAL DC2028A
Quick Start Procedure
The following procedure describes how to set up a DC2028A demo system.
1.Download and install the LTpowerPlay GUI: www.linear.com/ltpowerplay
2.Remove the board from the ESD protective bag and place it on a level surface. Connect the DC1613 I2C/SMBus/
PMBus controller to the DC2028A board using the 12-pin ribbon cable.
Figure 2. Connecting DC2028A Board and the DC1613 I2C/SMBus/PMBus Controller
3.Confirm that the CONTROL switch is set to the RUN position.
4.Plug the USB-to-I2C/SMBus/PMBus controller into a USB port on your PC. The board should power-up with all power
good LEDs and 5V LED illuminated green. The USB-to-I2C/SMBus/PMBus controller supplies ~100mA of current
which should be sufficient for a single demo board.
5.If multiple boards are being powered, connect a 12VDC power supply with > 0.5A capacity to the VIN input jack of
the DC2028A.
6.Launch the LTpowerPlay GUI.
a. The GUI automatically identifies the DC2028A and builds a system tree for each
power manager. The system tree on the left hand side will look like this:
Note: For multiple board arrays, the GUI automatically ensures each device has a unique address. In this scenario, it is recommended at this point to store these addresses to NVM (EEPROM) by clicking the RAM to NVM icon in the toolbar.
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DEMO MANUAL DC2028A
Quick Start Procedure
b.A green message box will be displayed momentarily in the lower left hand corner confirming that the DC2028A
is communicating.
c. Save the demo board configuration to a (*.proj) file by clicking the Save icon. This creates a backup file. Name
it whatever you want.
7.The CONTROL switch is configured to control all eight channels. Slide the switch to RUN to enable, OFF to disable all channels. For multiple board arrays, the CONTROL switch is wired to a signal that is common across all
boards. All CONTROL switches must be set to the RUN position to enable all boards.
LOADING A DC2028A CONFIGURATION (*.proj) FILE WITH THE GUI
1.In the upper left hand corner of the GUI, File > Open > browse to your *.proj file. This will load the file into the GUI.
2.Click on the Go Online
icon, then click on the PC->RAM icon.
This loads the configuration into the
working RAM of the LTC2977.
3.To store the configuration to NVM (EEPROM), click on the RAM->NVM icon.
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DEMO MANUAL DC2028A
DC2028A Details – Top Side
Figure 3. DC2028A Top Side Details
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DEMO MANUAL DC2028A
Common Demo Board Operations
MARGIN ALL RAILS
The LTC2977 Power System Manager on the DC2028A not only monitors
each of the eight outputs but can margin the outputs either high or low.
Margining is the operation that moves a rail either up or down for testing
purposes. It allows a system to be fully characterized over supply limits
without the use of external hardware or resources. The GUI provides an
easy way to margin all rails high or all low by clicking one of four buttons.
To invoke the margining dialog, click the GroupOp icon in the toolbar.
The buttons labeled ignore faults will margin without creating a fault
even if the fault limits are exceeded.
A look at the telemetry window shows the effect of the margin high or
margin low operation. The screen shot shows all rails going from nominal
setpoints to margin high, margin low, and back to nominal voltages.
The LTC2977 has a multiplexed ADC that is used to provide voltage, current, and temperature readback values. The telemetry plot in the GUI is
similar to a multi-channel oscilloscope which is capable of displaying any
parameter that is displayed in the telemetry window. Due to the nature
of a multiplexed ADC converter, it has an associated ADC loop time. The
total ADC loop time (~100-160ms) for a given channel is dependent on
the device’s configuration.
CREATING A FAULT
There is a pushbutton on the DC2028A board that is used to force a fault
and demonstrate the demo board’s ability to detect it and respond according to the configuration. When depressed, the pushbutton creates a fault
(short to ground) on channel 7, the 3.3V output (GUI channel U0:7). The
user should see all outputs power off, the fault LED momentarily illuminate,
the alert LED illuminate continuously, and all rails sequence
back on after a retry period. The user may also short any
power supply output indefinitely. This is a good way to
induce UV faults and shows that a shorted channel will not
be damaged. Use a jumper wire or a coin to short any
output.
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DEMO MANUAL DC2028A
Common Demo Board Operations
The LTC2977 has a feature which allows supply rails to
sequence off in a controlled manner in response to a fault
condition, as opposed to turning all rails off immediately.
The SequenceOffOnFault bit in the MFR_CONFIG_LTC2977
register sets this behavior on each channel. The DC2028A
demo board has been configured to sequence off all channels
when a fault occurs. Pressing the SHORT pushbutton causes
the Fault pin to be asserted low which triggers all rails to
power down based on the TOFF_DELAY times.
Figure 4 shows FAULTB asserting low, and each of the channels sequencing off per the TOFF_DELAY settings. Figure 5
shows the same except that the 3.0V rail (CH4) does not have its SequenceOffOnFault bit set. The 3.0V rail powers
down immediately as defined by the fault response setting.
Figure 4. Sequencing Off (SeqOffOnFault=1)
Figure 5. Sequencing Off (SeqOffOnFault=0)
CLEARING A FAULT
To clear a fault, the user may click the CF icon in the GUI or simply push the RESET pushbutton on the
demo board. In both cases, the red (+) on the CF icon and alert LED on the board will be cleared. You will
notice that all rails are automatically re-enabled after a programmable retry period. The alert LED may be
cleared by clicking the clear faults (CF) icon in the GUI. After clearing faults, the system tree may remain yellow if any
non-volatile fault logs are present. For further information, see the Working with the Fault Log section.
RESETTING THE DC2028A
A reset pushbutton is provided on the board. To reset all devices on the DC2028A board and reload the EEPROM
contents into operating memory (RAM), press RESET (SW2) on the DC2028A.
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DEMO MANUAL DC2028A
Common Demo Board Operations
DC2028A LEDs
Each individual channel on DC2028A has its own green power good LED (CH0 through CH7). When USB power (DC1613
controller) or external power (6V to 14V jack) is applied, the 5V green LED will illuminate, indicating that the LTC2977
Power System Manager is powered. The red LEDs will illuminate when an alert or a fault has occurred.
SEQUENCING OUTPUT CHANNELS
The LTC2977 has been preconfigured with different TON_DELAY values for each channel. The TON_DELAY parameter
is applied to each device relative to the respective CONTROL pin. When multiple demo boards are connected together,
all CONTROL pins are wire OR’d. Therefore the TON delays are enforced relative to one edge. The same applies to
TOFF_DELAY values. When the CONTROL switch is set to the OFF position, all rails will power down sequentially
based on each of the device’s TOFF_DELAY values. Figure 6 shows an oscilloscope screen capture of three output rails
sequencing up and down in response to the CONTROL pin.
Figure 6. Sequencing Output Channels with DC2028A Using TON_DELAY and TOFF_DELAY
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DEMO MANUAL DC2028A
Common Demo Board Operations
Each channel has an LED which visually indicates if the channel has power. When the CONTROL pin is switched on
and off, you will observe the relative on/off timing of the eight channels.
Figure 7. TON_DELAY Configuration
Figure 8. TOFF_DELAY Configuration
For the LTC2977, the TON_DELAY and TOFF_DELAY values extend to 13.1 seconds, providing very long sequencing
on and off of power supply rails.
WHY AM I OFF? TOOL
Use the Why am I Off? tool in the LTpowerPlay GUI to diagnose the reason a power supply channel is turned off. The
tool can be located in the top right corner of the GUI, above the Register Information tab. Hover your cursor over this
tab to show the tool.
Figure 9. Why Am I Off? Tool in the LTpowerPlay GUI
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DEMO MANUAL DC2028A
Advanced Demo Board Operations
WHAT IS A FAULT LOG?
A fault log is a non-volatile record of the power system leading up to the time of fault. It holds the most recent monitored values (uptime, voltage, current, temperature) that can be analyzed to help determine the cause of the fault. It
is a powerful diagnostic feature of the LTC2977 on the DC2028A demo board.
CREATE A FAULT LOG
To create a fault log, you must create a fault, as described in the
Creating A Fault section on page 7. If multiple boards are configured,
select the appropriate device in the system tree by clicking on the
appropriate LTC2977 chip. We will proceed to work with the fault log.
WORKING WITH THE FAULT LOG
Once a fault has occurred, the Fault Log (FL) icon will show a red (+) sign on it, indicating that the GUI
has detected a fault log in the device. Clicking the icon will bring up a dialog box. Note that it is context
sensitive. If multiple DC2028A boards are connected, be sure that the desired device is selected in the
system tree.
Notice that the checkbox Log to EEPROM on Fault is checked.
Once a fault occurs, the device will automatically write the fault
log data to EEPROM (NVM). At this point, the log is locked and
will not change until it is cleared by the user. To read the EEPROM
log data, first click the NVM to RAM button. At this point the RAM
Log is locked and not updated even though the telemetry readings
continue. Click the Read RAM Log button. The log data will appear
in the text box below.
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DEMO MANUAL DC2028A
Advanced Demo Board Operations
The log contains timestamp, up-time, channel voltage
readings, an input voltage reading, an on-chip temperature
reading, etc. There will be a number of loops; each loop
contains data obtained in one ADC loop time with the
most recent ADC loop data on top and the oldest data at
the bottom of the log. The up-time indicates, at the time
of fault, the amount of time the device had been powered
up or time since the previous reset.
In this case, the fault log will show that channel U0:7
faulted due to a VOUT_UV_FAULT condition. On the previous telemetry loop, the channel voltage reading was a
nominal value (3.3V).
To clear the fault log, click the Clear/Rearm EEPROM Log
button. This allows the selected device to be ready for a
new fault event. To clear all faults, click the clear faults
(CF) icon.
FAULT SHARING SETUP IN THE GUI
Fault sharing provides a means of propagating a fault detected by a power
manager to other power managers via FAULT pins. Use the Fault Sharing Setup
Tool to configure the fault sharing in the GUI. Select the LTC2977 in the system
tree. Go to Utilities > Fault Sharing Diagram. For more details on this topic,
please refer to the Fault Management section in the data sheet.
The fault sharing dialog will appear as shown in Figure 10. All
response and all propagate switches are closed by default. In this
configuration, a fault on a channel will shut down all LTC2977
channels, and a fault on any given channel will propagate to all
channels on the DC2028A demo board since the fault pins are
tied together.
NOTE: All FAULT pins of the LTC2977 are tied together on the
DC2028A demo board. These pins are open drain and have a
common pull-up resistor to provide a logic high level (inactive).
All FAULT pins are active low.
Figure 10. Fault Sharing Utility in LTpowerPlay GUI
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DEMO MANUAL DC2028A
Advanced Demo Board Operations
There are two types of actions to fault conditions: How a channel responds to another channel’s fault and whether a
particular channel propagates its fault to other channels. FAULT pins are bidirectional, meaning the device may drive
its fault pin low (output) or may respond to the fault pin when another device drives it low (input). Because all fault
pins are wire OR’d on the DC2028A, this hardware configuration allows one to program each device’s fault settings on
a channel-by-channel basis. By default, the LTC2977 is configured to shut down its channels if the FAULT pin is low
and to propagate its own fault via the FAULT pin. You can think of the Response switches as shut this channel down
when another channel faults, and the Propagate switches as drive a fault pin to broadcast to other channels that this
channel faulted.
FAULT CONFIGURATION EXAMPLE
Let’s explore two different examples. Suppose we do not want
channel U0:0 (CH0 1.2V rail) to propagate its fault to the other
channels when it faults. And suppose we do not want channel
U0:1 (CH1 1.5V rail) to shut down in response to another channel’s fault. We can configure the switches as shown in
Figure 11. Simply click the switches to open/close. Click
OK to close the dialog box. Click the PC->RAM icon to
write the changes to the DC2028A.
We can now create a fault on U0:0 (CH0) by shorting the output
to ground. You may use a coin or a jumper to temporarily connect
CH0 to the GND turret. You will notice that the channel shuts off
but the other channels remain powered up because its fault is not
propagated to the other channels. After the retry period, channel
U0:0 (CH0) will power back up. We can now observe the effect of
changing the response setting on U0:1 (CH1). If you short U0:3
(CH3 2.0V rail) to ground, notice that all rails shut down except
U0:1 (CH1). This is an example of a keep alive channel that remains
powered up independent of faults to other channels.
Figure 11. Updated Fault Sharing Configuration
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DEMO MANUAL DC2028A
Setup Procedure for multi-board arrays
Up to eight DC2028A boards can be cascaded to control
up to 64 independent power supplies. The number of
boards is limited by an I/O expander chip that has three
address pins, allowing eight different combinations. This
setup demonstrates the coordinated fault responses and
accurate time base shared across multiple power system
managers.
Procedure:
1.Stack the boards side-by-side by plugging JP1 of one
board into JP2 of another DC2028A board.
2.Ensure different slave address settings for each of the
boards. The address of each DC2028A board is set by
the DIP switch JP1 on the backside of the board. The
setting must be unique for each board in the array.
3.Plug the 12V VIN power into one of the boards as shown
in Figure 12 below. Only one 12V power source is allowed.
4.The USB-to-I2C/SMBus/PMBus controller may be
plugged into any board. If no DC2028A boards show up
in the GUI, click the magnifying glass icon to
enumerate the I2C bus and find the addresses
of the parts. Go to step #2 to ensure that each
board has a unique DIP switch setting.
5.Since the individual CONTROL lines are connected
across the boards (CTRL is a common signal across
all boards in the array), make sure that all CONTROL
switches are set to the RUN position.
6.Relaunch LTpowerPlay. After launching, LTpowerPlay
will enumerate the entire board array and build a representative system tree and read all hardware settings
into the GUI.
ATTENTION: Once the GUI has launched, click the
RAM->NVM button in the toolbar to ensure that
the slave addresses are retained after a power off
or reset. Otherwise you may lose communication
with the slaves after a power cycle or reset event.
Figure 12. Array of Multiple DC2028A Demo Boards
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DEMO MANUAL DC2028A
Setup Procedure for multi-board arrays
ENSURING SLAVE ADDRESSES DO NOT CONFLICT
There is a small DIP switch on the backside of the DC2028A.
It is used to set the slave address of an I/O expander which
allows the addition of multiple boards to a setup. The I/O
Figure 13. DIP Switch Set to All 0’s (0x20)
expander has a base address of 0x20. The DIP switch
settings set the offset. The three switches that may be
changed are labeled A0, A1, A2. Examples below set the
boards to addresses 0x20 and 0x27.
Figure 14. DIP Switch Set to All 1’s (0x27)
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DEMO MANUAL DC2028A
DC2028A Details – TOP
Table 1. DC2028A - Default Switch Configuration (Default Position Shown in Grey in the Figure Above)
REFERENCE DESIGNATOR
SIGNAL NAME
USAGE
DEFAULT
JP3 (Bottom)
A0, A1, A2
DIP Switch Used to Set the Address Offset
OPEN
S1
CONTROL0
Switch Used to Enable/Disable the CONTROL0
Input Pin of LTC2977
RUN
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DEMO MANUAL DC2028A
DC2028A Details – Bottom
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DEMO MANUAL DC2028A
Parts List
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
1
U6
IC 8-CH PWR SYSTEM MANAGER 64-QFN
Linear Technology: LTC2977CUP
2
3
C12, C18, C19
CAP CER 0.1µF 16V 10% X7R 0603
NIC: NMC0603X7R104K16TRPF
Additional Demo Board Circuit Components
3
8
C1, C2, C3, C4, C28, C29, C30,
C31
CAP CER 220pF 50V 10% NPO 0603
NIC: NMC0603NPO221J50TRPF
4
9
C5, C6, C7, C8, C21, C22, C23,
C24, C41
CAP CER 10µF 10V 10% X5R 1210
AVX: 1210ZD106KAT2A
5
1
C9, C45
CAP CER 10µF 25V 20% X5R 1206
Taiyo Yuden: TMK316BJ106ML-T
6
11
C10, C20, C37, C38, C39, C40,
C46, C50, C51, C52, C53
CAP CER 0.1µF 16V 10% X7R 0603
NIC: NMC0603X7R104K16TRPF
7
2
C11, C49
CAP CER 68pF 50V 5% NPO 0603
AVX: 06035A680JAT2A
8
9
C13, C33, C34, C35, C36, C54,
C55, C56, C57
CAP CER 22µF 10V 10% X5R 1210
Kemet: C1210C226K8PACTU
9
1
C14
CAP CER 47pF 50V 5% NPO 0603
AVX: 06035A470JAT2A
10
7
C15, C16, C17, C25, C26, C27,
C42
CAP CER 1µF 16V 10% X7R 0603
Taiyo Yuden: EMK107B7105KA-T
11
1
C32
CAP TANT 47µF 16V 20% 2917
Kemet: T520D476M016ATE035
12
2
C43, C47
CAP CER 4.7µF 16V 10% X5R 0603
TDK: C1608X5R1C475K
13
1
C44
CAP CER 10000pF 25V 10% X7R 0603
TDK: C1608X7R1H103K
14
1
C48
CAP CER 4.7pF 50V NPO 0603
Murata: GRM1885C1H4R7CZ01D
15
1
D1
DUAL DIODE SCHOTTKY 30V CC SOT-323-3
Diodes/Zetex: SBR0330CW-7
16
8
L1, L2, L3, L4, L6, L7, L8, L9
INDUCTOR SHLD POWER 4.7µH SMD
Abracon Corporation: ASPI-0315FS-4R7M-T2
17
1
L5
INDUCTOR POWER 2.2µH 2.85A SMD
Vishay: IHLP1616BZER2R2M01
18
9
LED3, P1, P2, P3, P4, P5, P6, P7,
P8
LED GREEN SS TYPE BRIGHT SMD
Panasonic - SSG: LNJ337W83RA
19
2
LED1, LED2
LED RED HI BRT SS TYPE LO CUR SM
Panasonic - SSG: LNJ208R8ARA
20
9
Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8,
Q9
MOSFET N-CH 30V 900MA SOT323-3
Vishay/Siliconix: SI1308EDL-T1-GE3
21
17
R1, R2, R3, R4, R37, R38, R39,
R40, R45, R46, R47, R48, R68,
R80, R81, R82, R83
RES 100kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603100KFKEA
22
1
R5
RES 200kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603200KJNEA
23
1
R6
RES 115kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603115KFKEA
24
1
R7
RES 80.6kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060380K6FKEA
25
1
R8
RES 66.5kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060366K5FKEA
26
9
R9, R10, R11, R12, R16, R26,
R27, R28, R29
RES 3.01kΩ 1/10W 1% 0603 SMD
NIC: NRC06F3011TRF
27
12
R14, R18, R19, R22, R23, R30,
R35, R36, R57, R58, R60, R88
RES 10.0kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060310K0FKEA
28
2
R15, R71
RES 73.2kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060373K2FKEA
29
1
R17
RES 46.4kΩ 1/10W 1% 0603 SMD
NIC: NRC06F4642TRF
30
2
R20, R25
RES 249Ω 1/10W 1% 0603 SMD
NIC: NRC06F2490TRF
31
1
R21
RES 1.00kΩ 1/10W 1% 0603 SMD
NIC: NRC06F1001TRF
32
2
R24, R59
RES ARRAY 10kΩ 4 RES 1206
Vishay Dale: CRA06S08310K0JTA
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DEMO MANUAL DC2028A
Parts List
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
33
34
1
R31
RES 47.5kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060375K5FKEA
1
R32
RES 42.2kΩ 1/10W 1% 0603 SMD
NIC: NRC06F4222TRF
35
1
R33
RES 36.5kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060336K5FKEA
36
1
R34
RES 32.4kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060332K4FKEA
37
8
R41, R42, R43, R44, R84, R85,
R86, R87
RES 470Ω 1/4W 5% 1210 SMD
Vishay CRCW1210470RFKEA
38
8
R49, R51, R53, R55, R73, R75,
R77, R79
RES 100Ω 1/10W 1% 0603 SMD
NIC: NRC06F1000TRF
39
1
R50
RES 158kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603158KFKEA
40
1
R52
RES 174kΩ 1/10W 1% 0603 SMD
NIC: NRC06F1743TRF
41
1
R54
RES 196kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603196KFKEA
42
1
R56
RES 210kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603210KFKEA
43
0
R61 (OPT)
RES 10.0kΩ 1/10W 1% 0603 SMD
Vishay: CRCW060310K0FKEA
44
2
R62, R67
RES 698Ω 1/10W 1% 0603 SMD
Vishay: CRCW0603698RFKEA
45
1
R63
RES 2.49kΩ 1/10W 1% 0603 SMD
Vishay: CRCW06032K49FKEA
46
1
R72
RES 261kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603261KFKEA
47
1
R74
RES 294kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603294KFKEA
48
1
R76
RES 348kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603348KFKEA
49
1
R78
RES 442kΩ 1/10W 1% 0603 SMD
Vishay: CRCW0603442KFKEA
50
8
U1, U2, U3, U4, U9, U10, U11, U12 IC BUCK SYNC ADJ 0.3A SOT23-6
Linear Technology: LTC3405AES6#TRMPBF
51
1
U5
IC BUCK SYNC 2.5A 16QFN
Linear Technology: LTC3604IUD#PBF
52
1
U7
IC DUAL 4A DIODES 16-MSOP
Linear Technology: LTC4415IMSE#PBF
53
1
U8
IC 2WIRE BUS BUFFER 8MSOP
Linear Technology: LTC4313CMS8-2#PBF
Microchip: MCP23008-E/ML
54
1
U13
IC I/O EXPANDER I2C 8B 20QFN
55
1
U14
IC EEPROM 2kBIT 400kHz SOT23-5
Microchip Technology: 24AA02T-I/OT
56
1
U15
IC VREF SERIES PREC TSOT-23-6
Linear Technology: LT6654BMPS6-1.25#TRMPBF
57
1
U16
IC BUFFER DUAL NON-INV SC706
TI: SN74LVC2G34DCKR
Hardware: For Demo Board Only
58
1
J1
CONN PWR JACK 2.1 x 5.5mm HIGH CUR
CUI Inc: PJ-002AH
59
1
J2
CONN HEADER 12POS 2mm STR DL PCB
FCI: 98414-G06-12ULF
60
1
JP1
CONN RECEPT 2mm DUAL R/A 14POS
Sullins Connector Solutions: NPPN072FJFN-RC
61
1
JP2
CONN HEADER 14POS 2mm R/A GOLD
Molex Connector Corporation: 87760-1416
62
1
JP3
SWITCH DIP 4POS HALF PITCH SMD
C&K Components: TDA04H0SB1
63
4
MH1, MH2, MH3, MH4
SPACER STACKING #4 SCREW NYLON
Keystone: 8831
64
1
S1
SW SLIDE DPDT 6VDC 0.3A PCMNT
C&K Components: JS202011CQN
65
1
SW1
SWITCH TACTILE BLK SPST-NO 0.05A 12V
C&K Components: PTS635SL25SMTR LFS
SWITCH TACTILE RED SPST-NO 0.05A 12V
66
1
SW2
67
20
TERM SOLDER TURRET 0.219" 0.078"L
TP1, TP2, TP3, TP4, TP5, TP6,
TP7, TP8, TP9, TP10, TP11, TP12,
TP13, TP14, TP15, TP16, TP17,
TP18, TP19, TP20
C&K Components: PTS635SK25SMTR LFS
MILL-MAX: 2501-2-00-80-00-00-07-0
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19
DEMO MANUAL DC2028A
Schematic Diagram
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20
DEMO MANUAL DC2028A
Schematic Diagram
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21
DEMO MANUAL DC2028A
Schematic Diagram
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22
DEMO MANUAL DC2028A
Schematic Diagram
dc2028af
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.
23
DEMO MANUAL DC2028A
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) 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 LTC 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 LTC 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. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC 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 LTC application engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
dc2028af
24 Linear Technology Corporation
LT 0813 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
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●
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 LINEAR TECHNOLOGY CORPORATION 2013