Texas Instruments TPS54980EVM-022 User Manual

  E  ! "
User’s Guide
September 2003 PMP Systems Power
SLVU090
IMPORTANT NOTICE
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty . Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed.
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Mailing Address: Texas Instruments Post Office Box 655303 Dallas, Texas 75265
Copyright 2003, Texas Instruments Incorporated
EVM IMPORTANT NOTICE
Texas Instruments (TI) provides the enclosed product(s) under the following conditions: This evaluation kit being sold by TI is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION
PURPOSES ONLY and is not considered by TI to be fit for commercial use. As such, the goods being provided may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including product safety measures typically found in the end product incorporating the goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may not meet the technical requirements of the directive.
Should this evaluation kit not meet the specifications indicated in the EVM User’s Guide, 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 SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR S TATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user indemnifies TI from all claims arising from the handling or use of the goods. Please be aware that the products received may not be regulatory compliant or agency certified (FCC, UL, CE, etc.). 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.
EXCEPT TO THE EXTENT OF THE INDEMNITY SET FORTH ABOVE, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
TI currently deals with a variety of customers for products, and therefore our arrangement with the user is not exclusive.
TI assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or services described herein.
Please read the EVM User’s Guide and, specifically, the EVM Warnings and Restrictions notice in the EVM User’s Guide prior to handling the product. This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact the TI application engineer.
Persons handling the product must have electronics training and observe good laboratory practice standards. No license is granted under any patent right or other intellectual property right of TI covering or relating to any
machine, process, or combination in which such TI products or services might be or are used.
Mailing Address:
Texas Instruments Post Office Box 655303 Dallas, Texas 75265
Copyright 2003, Texas Instruments Incorporated
EVM WARNINGS AND RESTRICTIONS
It is important to operate this EVM within the input and output voltage ranges specified in the EVM User’s Guide.
Exceeding the specified input range may cause unexpected operation and/or irreversible damage to the EVM. If there are questions concerning the input range, please contact a TI field representative prior to connecting the input power.
Applying loads outside of the specified output range may result in unintended operation and/or possible permanent damage to the EVM. Please consult the EVM User’s Guide prior to connecting any load to the EVM output. If there is uncertainty as to the load specification, please contact a TI field representative.
During normal operation, some circuit components may have case temperatures greater than 55°C. The EVM is designed to operate properly with certain components above 60°C as long as the input and output ranges are maintained. These components include but are not limited to linear regulators, switching transistors, pass transistors, and current sense resistors. These types of devices can be identified using the EVM schematic located in the EVM User’s Guide. When placing measurement probes near these devices during operation, please be aware that these devices may be very warm to the touch.
Mailing Address:
Texas Instruments Post Office Box 655303 Dallas, Texas 75265
Copyright 2003, Texas Instruments Incorporated
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1 Introduction 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Background 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Performance Specification Summary 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Modifications 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3.1 Changing Output Voltage 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3.2 Switching Frequency 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3.3 Power Sequencing 1-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Test Setup and Results 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Input/Output Connections 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Efficiency 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Power Dissipation 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4 Output Voltage Regulation 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.5 Load Transients 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.6 Loop Characteristics 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.7 Output Voltage Ripple 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.8 Input Voltage Ripple 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.9 Power Up and Down 2-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Board Layout 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Layout 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Schematic and Bill of Materials 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Schematic 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Bill of Materials 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents
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1−1 Frequency Trimming Resistor Selection Graph 1-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−1 Connection Diagram 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−2 Measured Efficiency, TPS54980 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−3 Measured Circuit Losses 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−4 Load Regulation 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−5 Line Regulation 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−6 Load Transient Response, TPS54980 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−7 Measured Loop Response, TPS54980, V 2−8 Measured Loop Response, TPS54980, V
2−9 Measured Output Voltage Ripple, TPS54980 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−10 Input Voltage Ripple, TPS54980 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−11 Power Up with Tracking 2-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−12 Power Down With Tracking 2-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−13 Power Up With Ratiometric Sequencing 2-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−14 Power Down With Ratiometric Sequencing 2-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−15 Power Up With Core Voltage Rising First 2-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2−16 Power Up With Core Voltage Falling Second 2-12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3−1 Top-Side Layout 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3−2 Internal Layer 2 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3−3 Internal Layer 3 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3−4 Bottom Side Layout (looking from top side) 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3−5 Top Side Assembly 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−1 TPS54980EVM-022 Schematic 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
= 3 V 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I
= 4 V 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I
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1−1 Input Voltage and Output Current Summary 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1−2 TPS54980EVM-022 Performance Specification Summary 1-3. . . . . . . . . . . . . . . . . . . . . . . . . .
1−3 Output Voltage Programming 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4−1 TPS54980EVM-022 Bill of Materials 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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About This Manual
This user’s guide describes the characteristics, operation, and the use of the TPS54980EVM-022 evaluation module. It covers all pertinent areas involved to properly use this EVM board along with the devices that it supports. The physical PCB layout, schematic diagram, and circuit descriptions are included.
How to Use This Manual
This document contains the following chapters:
- Chapter 1—Introduction
Preface

FCC Warning
Trademarks
- Chapter 2—Test Setup and Results
- Chapter 3—Board Layout
- Chapter 4—Schematic and Bill of Materials
This equipment is intended for use in a laboratory test environment only. It gen­erates, uses, and can radiate radio frequency energy and has not been tested for compliance with the limits of computing devices pursuant to subpart J of part 15 of FCC rules, which are designed to provide reasonable protection against radio frequency interference. Operation of this equipment in other en­vironments may cause interference with radio communications, in which case the user at his own expense will be required to take whatever measures may be required to correct this interference.
- SWIFT and PowerPAD are trademarks of Texas Instruments.
Read This First
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Chapter 1
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This chapter contains background information for the TPS54980 as well as support documentation for the TPS54980EVM-022 evaluation module (HPA022). The TPS54980EVM-022 performance specifications are given, as well as modifications.
Topic Page
1.1 Background 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Performance Specification Summary 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Modifications 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction
1-1
Background
TPS54980EVM−022
3.0 V to 4.0 V
1.1 Background
The TPS54980 tracking dc/dc converter is designed to provide accurate power sequencing in applications where two or more voltages are required for a load. These types of applications include core and I/O power supplies for microprosessors, DSPs, and FPGAs. Typically, some specific relation between the core and I/O supply voltages has to be provided during the power up and power down sequences. The TPS54980 tracking dc/dc converter is capable of direct tracking, ratiometric tracking, and voltage sequencing with a second power source.
The TPS54980EVM−022 is a two-channel EVM demonstrating the flexibility inherent in the TPS54980 design for tracking and sequencing core and I/O voltages. The TPS54980 is used to generate the core voltage and is nominally set at 1.8 V. The nominal 3.3-V I/O voltage is provided by a TPS2013 distribution switch. Rated input voltage and output current range are listed in Table 1−1.
Table 1−1.Input Voltage and Output Current Summary
EVM Input Voltage Range Output Current Range
Core, −9 A to 9 A
I/O, 0 to 1.5 A
This evaluation module is designed to demonstrate the small PCB areas that may be achieved when designing with the TPS54980 regulator . The switching frequency is set at a nominal 700 kHz, allowing the use of a small footprint
0.65-µH output inductor.
The MOSFETs of the TPS54980 are incorporated inside the TPS54980 package. This eliminates the need for external MOSFETs and their associated drivers. The low drain-to-source on resistance of the MOSFETs provides the TPS54980 high efficiency and helps to keep the junction temperature low at high output currents.The compensation components are provided external to the IC and allow for an adjustable output voltage and a customizable loop response.
The TPS54980 device uses the TRACKIN pin to access the tracking and sequencing capabilities. An internal multiplexer circuit compares the voltage at this pin with the internal reference voltage and uses the lesser of the two as the reference for the output voltage regulation. When the output of another power supply or distribution switch is connected to the TRACKIN pin of the TPS54980, the output of the TPS54980 tracks the output of this other channel during power up or power down, until the voltage at the TRACKIN pin becomes higher than the internal reference voltage. By applying the other power supply output to the TRACKIN pin through an appropriate resistor divider network, any required power up and power down relation between the two output voltages of the regulators can be set by changing the ratio of the divider network.
1-2
Performance Specification Summary
Load transient
IO = 2.25 A to 6.75 A
Load transient
response IO = 6.75 A to 2.25 A
1.2 Performance Specification Summary
A summary of the TPS54980EVM−022 performance specifications is provided in Table 1−2. Specifications are given for an input voltage of 3.3 V and an output voltage of 1.8 V unless otherwise specified. The ambient temperature is 25°C for all measurements, unless otherwise noted. The data presented in Table 1−2 was compiled with no load on the I/O output. The maximum input voltage for the TPS54980 is 4 V.
Table 1−2.TPS54980EVM-022 Performance Specification Summary
Parameters Test Conditions Min Typ Max Units
Input voltage range 3.0 3.3 4.0 V Output voltage set point 1.8 V Output current range VI = 3 to 5.5 V −9 9 A Line regulation IO = 0 A to 3 A, VI = 3 V to 5.5 V ±0.1% Load regulation VI = 3.3 V, IO = 0 to 3 A ±0.2%
Voltage change Recovery time
response
Loop bandwidth VI = 3 V 63 kHz Phase margin VI = 3 V 56 _ Loop bandwidth VI = 4 V 75 kHz Phase margin VI = 4 V 49 _ Input ripple voltage 50 200 mV Output ripple voltage 6 10 mV Output rise time N/A ms Operating frequency 280 700 700 kHz Max efficiency VI = 3.3 V, VO = 1.8 V, IO = 1.0 A 89%
Voltage change Recovery time
−50 mV 400 µs
50 mV
400 µs
PK
PK
PP PP
Introduction
1-3
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