DEMO MANUAL DC1540B
LTC2977 8-Channel
Power System Manager
with EEPROM
DESCRIPTION
The DC1540B is a demonstration system for the
LTC
®
2977
8-channel I
2
C/SMBus/PMBus Power System Manager
with EEPROM. It consists of 2 circuit boards namely the
DC1360B and DC1361B. The DC1360B contains all the
circuitry needed to insert the LTC2977 into a power system
and control eight power supplies. The DC1361B contains
eight power supplies (LTM4603EV) which are configured
to be controlled by an LTC2977. Together these two boards
form a sophisticated, 8-channel, digitally programmable
power supply.
This demonstration system is supported by LTpowerPlay™
software and a graphical user interface (GUI) that enables
complete control of all the LTC2977 features. You can obtain
this GUI from the website www.linear.com/ltpowerplay.
com. LTpowerPlay and the DC1540B, create a powerful
development environment in which you can design config-
uration settings for the LTC2977. The configuration settings
can be stored in the LTC2977 EEPROM and also in a file,
which can be used to order pre-programmed devices.
LTpowerPlay displays all of the configuration settings and
real-time measurements that the LTC2977 performs and
allows easy access to the fault log created by the LTC2977.
The LTC2977 on the DC1360B comes pre-programmed with
EEPROM values appropriate for the eight power supplies
used on the DC1361B.
The LTC2977 can be configured to monitor current
on odd numbered channels. In the DC1540B, this
feature can be enabled on Channel 7 (see “Measur-
ing Current”). Channels 1 and 2 can be configured
to do coincident tracking of Channel 0 by using JP2
and JP3 (see “DC1361B Details – Top Side”). An LTC
Hot Swap™ circuit on the DC1361B enables the LTC2977 to
soft-start V
IN
and shut off V
IN
in response to output faults.
Multiple DC1540Bs can be cascaded together to form
a high channel count power supply (see “Multi-Board
Arrays”). This configuration demonstrates features of the
LTC2977 which allow timing and fault information to be
shared across multiple LTC2977s, allowing the formation
of a single, coherent power supply control system. This
configuration is easily supported by the LTpowerPlay
GUI and allows the user to configure up to 9 LTC2977s,
controlling up to 72 separate power supplies.
To get this demo system up and running, connect the
DC1540B to your computer using a DC1427A or a DC1613
(USB to I
2
C/SMBus/PMBus Controller). The following is
a checklist of items which you can obtain from the LTC
website or LTC Field Sales.
n
n
n
USB to I
2
C/SMBus/PMBus Controller (DC1613A)
LTpowerPlay GUI
LTC2977 Resistor Selection Tool for calculating
resistors values and proper DAC range settings
(in the GUI)
LTC2977 Features
• I
2
C/SMBus Communication
• Configuration EEPROM
• PMBus Compliant
• Fault Logging to Internal EEPROM
• Differential Input, 16-bit
∆S
ADC with less than ±0.25%
of Total Unadjusted Error Using On-Chip Reference
• Monitors Eight Output Channels and One Input Voltage
• Programmable Watchdog Timer
• 8-Channel Sequencer
• Eight 10-Bit OV/UV Supervisors
• Eight 10-Bit Margin/Trim DAC’s with Soft-Connect
• A Closed-Loop Digital Servo Accurately Trims the Outputs
• Supports Multi-Channel Fault Management
• Programmable Fault Responses
• On-Chip Digital Temperature Sensor
Design files for this circuit board are available at
http://www.linear.com/demo
L,
LT, LTC, LTM, Linear Technology, and the Linear logo are registered trademarks and
LTpowerPlay and Hot Swap are trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
dc1540bf
1
DEMO MANUAL DC1540B
Table 1. LTC2977 Performance Summary (Specifications are at T
A
= 25°C)
PARAMETER
V
PWR
Supply Input Voltage Range
V
DD33
Supply Input Voltage Range
ADC Total Unadjusted Error
ADC Voltage Sensing Input Range
ADC Current Sensing Input Range
ADC Voltage Sensing Resolution
ADC Current Sense Resolution
0V ≤ V
IN_ADC
≤ 6V
0mV <|V
IN_ADC
| < 16mV
16mV <|V
IN_ADC
| < 32mV
32mV <|V
IN_ADC
| < 63.9mV
63.9mV <|V
IN_ADC
| <127.9mV
127.9mV <|V
IN_ADC
|
Buffer gain setting 0
Buffer gain setting 1
V
SENSEP[n]
V
SENSEM[n]
Voltage Supervisor Sensing Resolution
Voltage Supervisor
Total Unadjusted Error
I
2
C Serial Clock Frequency
0V to 3.8V range: 4.096/1024
0V to 6V range: 8.192/1024
2V < V
IN_VS
< 6V, Low Resolution Mode
1.5V < V
IN_VS
< 3.8V, High Resolution Mode
0.8V < V
IN_VS
< 1.5V, High Resolution Mode
Low resolution
High resolution
V
IN
≥ 1V
CONDITION
VALUE
4.5V to 15V
3.13V to 3.47V
±0.25%
–0.1V to 6V
–170mV to 170mV
122µV/LSB
15.6µV/LSB
31.25µV/LSB
62.5µV/LSB
125µV/LSB
250µV/LSB
1.38mV/LSB
2.65mV/LSB
±1°C
0 to 6V
0 to 3.8V
–0.1 to 0.1V
4mV/LSB
8mV/LSB
±1.25 %
±1.0 %
±1.5 %
10kHz to 400kHz
Voltage Buffered IDAC Resolution
10 bits
Temperature Sensor TUE
Voltage Supervisor Input Voltage
Range (Programmable)
Demo System Specifications
Table 2. Specifications-DC1361B
V
OUT
Name
V
OUT_0
V
OUT_1
V
OUT_2
V
OUT_3
V
OUT_4
V
OUT_5
V
OUT_6
V
OUT_7
Nominal Voltage-Untrimmed
3.325V ± 1.5%
2.497V ± 1.5%
1.989V ± 1.5%
1.804V ± 1.5%
1.502V ± 1.5%
1.200V ± 1.5%
0.999V ± 1.5%
0.799V ± 1.5%
Notes:
• Load current less than 2A on each output is recommended.
• Max current into J11 (+12V) should be < 6A max.
• Output voltages can be margined by a minimum of
±15% from nominal with the default resistor values
on the DC1361B. These values can be easily changed.
See section Changing DC1361B Nominal Output Volt-
ages. Use the LTC2977 Resistor Selection Tool which
is accessed from LTpowerPlay.
dc1540bf
2
DEMO MANUAL DC1540B
What Can You Do With This Demo System ?
• Prototype your system. You can change the nominal
V
OUT
’s of the modules to match your system. You can
also change the range and resolution of margining. Set
sequencing. Set OV/UV limits. And much more!
• Create your own configuration that you can store in the
EEPROM of the LTC2977 or save to a file. This file can
be used to order pre-programmed parts.
• Test most conceivable fault scenarios. All outputs can
be shorted.
Demo System Hardware
Hardware required:
1. PC + USB cable
2. 12V, >0.5A power supply
3. USB to I
2
C/SMBus/PMBus Controller
4. DC1540B = DC1360B + DC1361B
Figure 1. Single LTC2977 Demo Setup Using DC1540B
DOWNLOAD GUI TO YOUR PC
LTpowerPlay can be downloaded from www.linear.com/ltpowerplay. Complete instructions are located there.
dc1540bf
3
DEMO MANUAL DC1540B
QUICK START PROCEDURE
The following procedure describes how to set up one DC1540B.
1. Remove both boards from bag.
2. Place boards on level surface. Connect boards together using the 54-pin edge connector. See below.
Figure 2. Plug Boards Together
3. On DC1360B, set jumpers and switches as follows. See also Table 3.
a. Set both SW1 and SW2 (CONTROL0 and CONTROL1) to GND.
b. Set JP5 to OFF
.
c. Make sure JP6 is installed.
d. Set JP3 (ASEL0) to LO and JP2 (ASEL1) to LO.
e. Set JP4 to ON.
4. On DC1361B, set jumpers and switches as follows. See also Table 3.
a. JP1 = INSTALLED
b. JP2, JP3 = SOFT START
c. SW1 = MASTER
5. Plug in the USB to I
2
C/SMBus/PMBus Controller into a USB port on your PC.
6. Connect a 12V power supply with >1/2 Amp capacity to the VIN+ and VIN– inputs of the green terminal block J11
on DC1361B. Do not turn on 12V yet. Be careful to hook up polarity correctly! See Figure 5.
7. If you have a DC1427A, connect to J4 on DC1360B as shown in Figure 3.
dc1540bf
4
Talking
京公网安备 11010802033920号
EEWORLD
