User's Guide
SNVU444 – May 2014
LM5066IEVM-626 Evaluation Module (EVM)
This user’s guide describes the LM5066I EVM (LM5066IEVM-626). LM5066IEVM-626 contains evaluation
and reference circuitry for the LM5066I. The LM5066I device combines a high performance hot swap
controller with a PMBus™ compliant SMBus/I2C interface to accurately measure, protect, and control the
electrical operating conditions of systems connected to a backplane power bus.
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Contents
Introduction ................................................................................................................... 3
1.1
Features .............................................................................................................. 3
1.2
Applications .......................................................................................................... 3
1.3
Electrical Specifications ............................................................................................ 3
Schematic ..................................................................................................................... 4
General Configuration and Description ................................................................................... 5
3.1
Physical Access ..................................................................................................... 5
3.2
Equipment Setup.................................................................................................... 6
Operation ..................................................................................................................... 6
Test Results .................................................................................................................. 7
Getting Started.............................................................................................................. 11
6.1
Hardware Setup Steps............................................................................................ 11
6.2
Device Evaluation ................................................................................................. 11
6.3
GUI Event Log ..................................................................................................... 13
6.4
Plotting Telemetry Data .......................................................................................... 14
6.5
Configuring the LM5066I Device ................................................................................ 14
6.6
Customizing the Design .......................................................................................... 16
Layout Guidelines .......................................................................................................... 18
Board Layout ................................................................................................................ 20
Bill of Materials ............................................................................................................. 23
List of Figures
...........................................................................................................
1
Startup Waveform
2
Startup into Short Performance ............................................................................................ 7
3
Overvoltage Performance
4
Undervoltage Waveform .................................................................................................... 8
5
Overload Performance ...................................................................................................... 9
6
Load Transient into Overload Performance .............................................................................. 9
7
Hot Short on Vout (Zoomed Out)
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........................................................................................
Hot Short on Vout (Zoomed In)...........................................................................................
Device Selector .............................................................................................................
Initial GUI Screen...........................................................................................................
LM5066I Block-Level Representation ...................................................................................
LM5066I Telemetry Display Options .....................................................................................
LM5066I GUI With the Telemetry Plotting Tool Enabled..............................................................
Device Configuration Panel ...............................................................................................
LM5066I Design Tool ......................................................................................................
Recommended Board Connector Design ...............................................................................
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Sense Resistor Connections .............................................................................................. 19
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Top Assembly ............................................................................................................... 20
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Top Layer.................................................................................................................... 20
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Internal Layer 1 ............................................................................................................. 21
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Internal Layer 2 ............................................................................................................. 21
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Bottom Layer ................................................................................................................ 22
List of Tables
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1
LM5066IEVM-626 Electrical and Performance Specifications at 25°C ............................................... 3
2
Connector Functionality ..................................................................................................... 5
3
Test Points .................................................................................................................... 5
4
Switches
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LM5066IEVM-626 BOM
...................................................................................................................... 6
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Introduction
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1
Introduction
The LM5066IEVM-626 evaluation board provides the design engineer with a fully functional intelligent
monitoring and protection controller board designed for positive voltage systems. This user’s guide
describes the various functions of the board, how to test and evaluate it, and how to use the GUI design
tool to change the components for a specific application. To use the advanced telemetry and monitoring
capabilities of this device, the user must install the Intelligent Power Manager GUI; however, the LM5066I
is capable of acting as a hot-swap and protection circuit without any software installation. For the latest
software information, check the LM5066I High Voltage System Power Management and Protection IC with
PMBus data sheet (SNVS950).
1.1
Features
•
•
•
•
•
•
•
1.2
Applications
•
1.3
Programmable current limiting and power limiting for complete SOA protection
Programmable fault timer to eliminate nuisance shutdowns
Programmable undervoltage and overvoltage protection
Programmable power good indicator
Programmable auto-retry or latch options
Fully Node Manager 2.0 and 2.5 compliant with I2C/SMBus interface and PMBus compliant command
structure
Real-time monitoring of VIN, VOUT, IIN, PIN, and VAUX with 12-bit resolution and 1-kHz sampling rate
Any live backplane insertion application
– Servers
– Telecommunications
Electrical Specifications
Table 1. LM5066IEVM-626 Electrical and Performance
Specifications at 25°C
Characteristic
Input voltage range (operating)
LM5066IEVM-626
40 to 60 V
Current operating
20 A
Power limit (nom)
239 W
Current limit (nom)
Fault timer (nom)
26 A
520 µs
UVLO rising (nom)
38 V
UVLO falling (nom)
35 V
Overvoltage rising (nom)
65 V
Overvoltage falling (nom)
63 V
PG threshold – vout rising (nom)
38 V
PG threshold – vout falling (nom)
35 V
Pass “Hot-Short” on output
Yes
Pass “Start into short”?
Yes
Is the load off until PG asserted?
Yes
Can a hot board be plugged back in?
Yes
Windows is a registered trademark of Microsoft Corporation.
PMBus is a trademark of SMIF, Inc.
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Schematic
2
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Schematic
D1
GATE
1N4148W-7-F
100 V
R1
10 kΩ
PSMN4R8-100BSEJ
Q1
C1
0.01 µF
Q2
VIN
TP1
J1
VINK
TP2
SENSEK
TP3
Pullup / Pulldown / High Z pins
PSMN4R8-100BSEJ
VOUT_S
TP6
Q3
VOUT
TP7
OUT
J3
VOUT
20 A
VIN
35 to 60 V
C2
1000 pF
D2
5.0SMDJ60A
60 V
J2
GND
R2
0.001 Ω
C3
1 µF
R8
95.3 kΩ
R9
150 kΩ
EN
1000pF
R10
DNP
7.68
GATE
TP5
U1
1
2
SENSE
TP4
VDD
SENSE
3
VINK
4
R13
11.5 kΩ
R14
3.74 kΩ
VIN
5
S1
SCL_ISO
SMBA_ISO
SDA_ISO
R15
R16
R17
10.0 kΩ
10.0 kΩ
10.0 kΩ
6
1
7
2
8
3
SCL_ISO
TP15
B12AP
SMBA_ ISO
R3
150 kΩ
FB
9
GND
GND
10
11
SDA_ISO
SDATP16
SCLTP17
SMBA TP18
TP8
FB
GATE
TP13
TP14
OVLO
C5
220 µF
R5
R6
4.99 Ω 4.99 Ω
C6
DNP
SDA_ISO
C4
220 µF
R4
0
12
SCL_ISO
13
14
OUT
GATE
SENSE
VIN_K
PGOOD_ISO
PGD
NC
PWR
TIMER
VIN
RETRY
NC
FB
UVLO/EN
CL
OVLO
VDD
AGND
ADDR0
GND
ADDR1
SDAI
ADDR2
SDAO
SCL
SMBA
SMBA_ISO
PG
TP9
R11
VAUX
DIODE
VREF
28
28.0 kΩ
25
22
B380-13-F
CJS-1201TA
SW2
80 V
TP24
CL
CL
19
18
3
CJS-1201TA
SW3
TIMER
TP10
C7
0.01 µF
TP25
ADR0
ADR0
1
2
3
FB
CL
VDD
CJS-1201TA
SW4
C8
TP26
ADR1
1 µF
ADR0
ADR1
1
2
3
ADR1
ADR2
VAUX
17
R18
CJS-1201TA
SW5
VAUX
TP12
TP27
ADR2
0
16
15
1
2
GND
ADR2
VREF
TP11
C10
1 µF
1
2
3
C9
1000 pF
PAD
LM5066IPWP
D3
J4
RETRYB
VDD
3
21
20
1
2
R12
26
23
RETRYB
VDD
100 kΩ
27
24
R7
10.5 kΩ
VDD
TP22
SW1
TP23
RETRYB
CJS-1201TA
Q4
Tem p. Diode
VIN_GND
GND VOUT_GND
TP19
TP20
TP21
SMBus connection for POL
J5
SCL_ISO
SDA_ISO
SMBA_ISO
CTRL1_ISO
CTRL2_ISO
R19
R20
R21
R22
R23
100
100
100
100
100
1
3
5
7
9
J6
2
4
6
8
10
PGOOD_ISO
TSW-105-08-G-D-RA
4
2
4
6
8
10
DNP
1
3
5
7
9
SCL_ISO
SDA_ISO
SMBA_ISO
CTRL1_ISO
CTRL2_ISO
PPPC052LJBN-RC
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General Configuration and Description
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3
General Configuration and Description
3.1
Physical Access
Table 2 lists the LM5066IEVM-626 connector and functionality, Table 3 describes the test point
availability, and Table 4 describes the switch functionality.
Table 2. Connector Functionality
Connector
Label
Description
J1
VIN
Power bus input. Apply bus input voltage between J1 and J2.
J2
GND
Power bus input return connector. Apply bus input voltage between J1 and J2.
J3
VOUT
Switched bus output. Apply the load between J3 and J4.
J4
GND
Switch bus output return connector. Apply the load between J3 and J4.
J5
PMBus interface
Table 3. Test Points
Test Point
Label
Description
TP1
VIN
TP2
VINK
TP3
SENSEK
Sense Kelvin sense pin on sense resistor
TP4
SENSEK
Sense pin test point
TP5
GATE
TP6
VOUT_S
TP7
VOUT
Positive supply input
Positive supply Kelvin sense pin on sense resistor
Gate drive output
Output voltage at the pass FET
Output voltage at the load
TP8
FB
Power Good feedback
TP9
PG
Power Good indicator
TP10
TIMER
Timing capacitor voltage
TP11
VREF
Internal reference voltage
TP12
VAUX
Auxiliary ADC input
TP13
EN
TP14
OVLO
OVLO pin voltage
TP15, TP19, TP20, TP21
GND
Circuit ground
TP16
SDA
SMBus input/output
TP17
SCL
SMBis clock
TP18
SMBA
TP22
VDD
TP23
RETRYB
UVLO/EN pin voltage
SMBUS alert line (active low)
Internal sub-regulator 4.85-V output
Fault retry input
TP24
CL
TP25
ADR0
SMBus address line 0
TP26
ADR1
SMBus address line 1
TP27
ADR2
SMBus address line 2
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General Configuration and Description
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Table 4. Switches
3.2
Switch
Label
S1
EN
SW1
RETRY
Description
Enable and disable of the hotswap
Fault retry input
SW2
CL
SW3
ADR0
Current limit range
SMBus address line 0
SW4
ADR1
SMBus address line 1
SW5
ADR2
SMBus address line 2
Equipment Setup
1. Set the input power supply voltage to the desired operating input voltage.
2. Turn the power supply off.
3. Connect the positive voltage lead from the power supply to J1 (VIN). Connect the ground lead form the
power supply to J2 (GND).
4. Place a voltmeter or oscilloscope probe across J3 and J4 (VOUT).
4
Operation
1.
2.
3.
4.
6
Turn on the power supply.
Enable S1 ON.
Vary the input voltage and add load current as necessary for test purposes.
Apply fault conditions to observe fault performance as necessary.
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Test Results
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5
Test Results
This section provides typical performance waveforms for the LM5066IEVM-626 with VIN = 48 V at no load
(unless otherwise specified). Actual performance data is affected by measurement techniques and
environmental variables; therefore, these curves are presented for reference and may differ from actual
results obtained.
Figure 1. Startup Waveform
Figure 2. Startup into Short Performance
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Test Results
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Figure 3. Overvoltage Performance
Figure 4. Undervoltage Waveform
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Figure 5. Overload Performance
Figure 6. Load Transient into Overload Performance
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Test Results
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Figure 7. Hot Short on Vout (Zoomed Out)
Figure 8. Hot Short on Vout (Zoomed In)
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Getting Started
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6
Getting Started
The LM5066IEVM is supplied with the PMBus address set to 0x40 as dictated by the jumper configuration
of the ADR0, ADR1, and ADR2 jumper connections.
The first step to evaluate the telemetry features of LM5066I is to install the GUI software. The software
can be found under software on the product page. This file should be executed on a PC running
Windows® XP or later to install the software.
6.1
Hardware Setup Steps
1.
2.
3.
4.
Connect the input supply to the VIN (J1) and GND (J2) banana plugs.
Connect the load to the VOUT (J3) and GND (J4) banana plugs.
Connect the FTDI Dongle to the 10-pin connector on the left side of the board to J5.
Connect the supplied mini USB cable from the FTDI dongle to an USB port on a PC.
When the FTDI dongle is connected for the first time, the user will be prompted to install the device
drivers. For the most current driver installation procedure, refer to the README.TXT file in the installation
directory.
For a hot swap circuit to function reliably, TI recommends a low inductance connection to the input supply.
Its purpose is to minimize voltage transients which occur when the load current changes or is shut off. If
the user is not careful, wiring inductance in the supply lines will generate a voltage transient at the input
which can exceed the absolute maximum rating of the LM5066I, resulting in its destruction. To protect
against such voltage transients, TVS device D2 is provided to clamp the voltage at the input to within safe
operating limits. Likewise, Schottky diode D3 is provided on the output to clamp the output from going
excessively negative during short circuit events.
6.2
Device Evaluation
After configuring the hardware connections, apply an input voltage of 48 V to the device. The current
hardware configuration allows the LM5066I device to work from 40- to 60-V input supply voltage; however,
this guide assumes an input voltage of 48 V. Launch the GUI by going to the Windows Start menu → All
Programs → PMBManager-x.xxxxx → PMBusManager. A pulldown menu should come up with a list of
devices populated. Select the "LM5066" option as shown in Figure 9.
Figure 9. Device Selector
The device should be detected on the PMBus, and the initial load screen should appear as shown in
Figure 10.
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Figure 10. Initial GUI Screen
If a device is not detected, there is an option to rescan, ignore, or exit the GUI. If the hardware is intended
to be connected, check the USB connection to the PCB, FTDI connection to the evaluation module, and
verify that the power is present on the evaluation PCB by measuring the voltage between the VIN_S and
VIN_GND test points. Ignoring the detection message allows use of the integrated design tool without the
hardware connected.
Figure 11. LM5066I Block-Level Representation
Click on the detected device ID (TI-LM5066I-AA) to display a block level representation of the device as
shown in Figure 11. The block level view of the device provides a display of all the telemetry data as well
as most of the faults and warnings supported by the device. The faults and warnings supported are
generally associated with an invalid input or output condition.
The faults shown on the left side of the block representation are generally associated with the input. These
include input under-voltage (UV), input over-voltage (OV), FET fail (FF), and input over-power (OP). The
SMBus alert status, SMBA, is also shown on the left side and will turn red during any warning or fault
event. To facilitate the evaluation of the device, SMBus alerts are automatically cleared by the GUI.
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The faults shown on the right side of the block representation are associated with the output. These
include output over-voltage (OV), power good status (PGD), output over-current (OC), and overtemperature (OT). There is also an indicator if the output is in the latched off state (LO). The device
latches the output off after the number of user-programmable retries is exceeded. To clear the latched off
condition, the output can be toggled off and on by the red power button located in the top right of the
LM5066I block representation.
To show a repetitive update of the device telemetry and status, click the Play button at the top of the
screen. The Play button starts an active telemetry log of the gathered data. Clicking the Stop button stops
the telemetry collection and allows for the log file to be viewed and saved. The Pause button pauses both
the displaying and logging of telemetry information.
To enable or disable specific telemetry, click the Display Options button on the block representation and
choose the desired telemetry to display (see Figure 12).
Figure 12. LM5066I Telemetry Display Options
Note that turning off the various warning options does not mask the faults from issuing an SMBus alert; by
turning off warning options, the selected warnings are just not displayed if they occur. The device is
capable of masking various faults, and this functionality can be setup in the device configuration panel.
6.3
GUI Event Log
A GUI event log is provided to keep track of GUI configuration changes and device fault events. To
display the event log, select View from the main menu bar, then Telemetry Data Log. The event log
appears on the left side of the main GUI window. The event log can be detached and expanded if desired
by left clicking on the event log window and dragging the window with the mouse to the desired location.
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Getting Started
6.4
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Plotting Telemetry Data
To enable telemetry data plots, click on the sine wave button located on the LM5066I block
representation. After enabling the telemetry, a prompt appears requesting entry of the GUI sample
interval, plot interval, and plot depth. For most cases, the default rates and depths are acceptable. The
plotting tool allows the user to select the desired data to be plotted. Up to two different parameters can be
plotted at the same time as shown in Figure 13.
Figure 13. LM5066I GUI With the Telemetry Plotting Tool Enabled
Telemetry data is plotted as a black line that continually updates as the device is queried. In addition to
the telemetry data, the relevant warning and fault thresholds are also plotted. Warning thresholds are
shown as orange lines while fault thresholds are shown in red and blue.
From the Plot menu option in the main menu bar, the user can disable the plotting grid and the warning
and fault lines.
6.5
Configuring the LM5066I Device
Warning thresholds, temperature fault threshold, protection ranges, fault masking, and averaging can be
configured in the Device Configuration panel. This panel, shown in Figure 14, is enabled by clicking View
→ Device Configuration.
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Figure 14. Device Configuration Panel
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The Warning and Fault Threshold tab allows configuration of the input undervoltage, input overvoltage,
output undervoltage, input overcurrent, input power, and overtemperature warnings. This tab also allows
adjustment of the overtemperature fault threshold. The hardware design sets the fault threshold for the
input over-voltage and under-voltage, current limit, power limit, and power good. Decimal values for the
thresholds are shown in the text box located to the right of the slider bar. The hexadecimal value of the
setting is located above the decimal values setting, which can be useful when developing software for this
device.
The fault behavior tab allows the user to set the device fault configuration and fault masking. The fault
configuration section allows the user to set the number of retries, as well as the circuit breaker and current
limit thresholds. The number of retries can be set by the RETRY pin to be infinite or latched off. Through
software, the number of retries can be set to 0 (latch-off), 1, 2, 4, 8, 16, or infinite. The software settings
are independent of the hardware settings; however, if the power is cycled, the device defaults to values
dictated by the hardware. Current limit power-up values are also set by the hardware. The values for
current limit can be set to either 26 mV (CL = VDD) or 50 mV (CL = GND). The circuit breaker threshold
can also be set in software to either 1.9× or 3.9× the current limit value through the software. Fault
masking is possible for many of the device fault conditions. Fault conditions allow masking of both the
MOSFET response and the SMBus alert signal. Note that if a fault occurs repeatedly while the MOSFET is
masked, damage to the MOSFET may result. This feature is allowed primarily for debug purposes. Faults
that do not shut off the MOSFET and only issue a SMBus alert, also allow masking of the alert. Note the
power-up default setting for the Power Good signal is to mask the SMBus alert, in order to ensure that
SMBus alert is not asserted immediately after power-up.
For convenience, the Device Configuration panel can be undocked by holding down the left mouse button
while the cursor is at the top of the panel and dragging it to the desired location.
6.6
Customizing the Design
The GUI assumes the hardware configuration is set to default LM5066I evaluation board configuration. If
any of the components are changed, the device hardware configuration needs to be updated in the Design
Tool section. To open the design tool, click the Wrench button located on the LM5066I block
representation, which will open the window displayed in Figure 15.
Figure 15. LM5066I Design Tool
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Design inputs are keyed in on the left side following steps 1 though 5.
1. Enter the general operating conditions in step 1 of the design tool. These inputs help set bounds on
the startup time and application voltage ranges.
2. Step 2 allows the user to tailor the MOSFET protection features to be specific to the target application.
Current limit is pin-configurable and software-configurable, and circuit breaker is software-configurable.
If the CL switch is used to set the current limit, ensure the GUI selection matches the pin-configurable
CL bit setting on the board. By clicking on the MOSFET SOA Profile button, the user can select SOA
data from several popular MOSFETs or enter the SOA data for the desired MOSFET. The resistor
RPWR can then be calculated to keep Q1 or Q3, or both, within its SOA profile.
3. Step 3 allows the user to select the undervoltage lockout (UVLO) and overvoltage lockout (OVLO)
values, and power good (PGD) thresholds. Note that with the correct values for R8, R9, R13, R14, and
R3 and R7 installed, the LM5066I indicates a fault condition when the input or output voltages, or both,
are outside of their programmed range.
4. Step 4 allows the user to set the fault time-out period and the fault response. The fault time-out should
be set to be below the MOSFET SOA data for a given time. For example, if a design is done to adhere
to the 10 ms pulsed MOSFET SOA data, the desired fault time-out must be less than 10 ms. The fault
time-out time entered sets the value for CT. It also sets the insertion delay and fault retry delay. The
initial power-up retry behavior is also selected in this design step. Make sure to change the RETRY
switch to match the design tool schematic when changing the default retry setting.
5. In step 5, the user enters the desired PMBus address. Note changing the PMBus address of the
device in step 5 does not change the device address, but shows how the address pins of the device
need to be configured to achieve a desired address. After the ADR pin switches are configured for a
particular address, power to the device needs to be cycled and the GUI restarted in order for the new
address to take effect.
When invalid or incorrect inputs are given to the design tool, text associated with the faulty input turns red.
Positioning the mouse cursor over the red text gives additional information about any design conflict.
Component and parametric results are shown to the right as well as the LM5066I safe operational area
(SOA) chart. The SOA chart shows the minimum, typical, and maximum SOA protection areas for a given
design. For a robust design, the SOA of the MOSFET used should be above the max protection SOA line
for all operating areas.
After a design is complete, the design should be saved by selecting the File menu, then Save. After the
hardware is modified to match the design, the GUI should be restarted and the hardware configuration file
loaded right after the device is detected and placed. If the values in the design tool are different than the
values on the board, erroneous telemetry and fault data are reported by the GUI. To return to the block
view of the device, press the Home button located at the far left in the menu bar.
The design tool is also useful to calculate the PMBus coefficients. With the correct value for current sense
resistor (R2), the tool calculates the correct coefficients to scale the raw telemetry data. The coefficients
can be viewed by selecting View from the main menu bar, and then selecting the PMBus Coefficient
Editor. When the PMBus Coefficient Editor is opened, press the Get All button to show the currently used
coefficients.
If desired, the results presented by the design tool can be calculated by hand using the equations
provided in the data sheet. However, note the design tool calculates parameters factoring in worst-case
tolerances, while the equations in the data sheet are based on typical thresholds.
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Layout Guidelines
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Layout Guidelines
The following guidelines should be followed when designing the PC board for the LM5066I:
1. Place the LM5066I close to the board’s input connector to minimize trace inductance from the
connector to the MOSFET.
2. Place a TVS, Z1, directly adjacent to the VIN and GND pins of the LM5066I to help minimize voltage
transients which may occur on the input supply line. The TVS should be chosen such that the peak
VIN is just lower the TVS reverse-bias voltage. Transients of ≥20 V over the nominal input voltage can
easily occur when the load current is shut off. A small capacitor may be sufficient for low current sense
applications (I
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