How it Works
Texas Instruments
Loading...
LMG1205HBEVM
User Manual
22 pgs1.46 Mb0

Texas Instruments LMG1205HBEVM User Manual

Using the LMG1205HBEVM
User's Guide
Literature Number: SNVU552
March 2017
Contents
Preface ........................................................................................................................................ 4
1 Description.......................................................................................................................... 6
1.1 EVM Features ............................................................................................................ 6
1.2 Typical Applications...................................................................................................... 7
2 EVM Kit Contents................................................................................................................. 7
3 Electrical Performance Specifications .................................................................................... 7
4 EVM Schematic.................................................................................................................... 8
5 Test Setup........................................................................................................................... 9
5.1 Test Equipment........................................................................................................... 9
5.2 List of Test Points....................................................................................................... 10
5.3 List of Terminals ........................................................................................................ 11
5.4 EVM Connections ...................................................................................................... 11
6 Test Procedure................................................................................................................... 12
6.1 Power-Up Procedure................................................................................................... 12
6.2 Shutdown Procedure................................................................................................... 13
7 Switching Waveforms ......................................................................................................... 13
8 EVM Assembly Drawing and PCB Layout.............................................................................. 15
9 List of Materials ................................................................................................................. 16
2
Table of Contents
Submit Documentation Feedback
SNVU552–March 2017
www.ti.com
1 LMG1205HBEVM Schematic .............................................................................................. 8
2 LMG1205HBEVM Board Top View ....................................................................................... 9
3 LMG1205HBEVM Board Bottom View ................................................................................... 9
4 HI Test Point (TP8) ........................................................................................................ 10
5 LI Test Point (TP9)......................................................................................................... 10
6 HS Test Point (TP12)...................................................................................................... 10
7 HB Test Point (TP4) ....................................................................................................... 10
8 HO Test Point (TP3) ....................................................................................................... 10
9 LO Test Point (TP11) ...................................................................................................... 10
10 LMG1205HBEVM Test Setup Connections ............................................................................ 11
11 Input and Output Waveforms Showing the Dead Time ............................................................... 13
12 Zoom in of the SW Node Running at 50% Duty Cycle................................................................ 14
13 48-V to 5-V Synchronous Buck Converter Operation Showing Inputs, SW Node, and V
14 LMG1205HBEVM-10 Top Layer and Components .................................................................... 15
15 LMG1205HBEVM-10 Bottom Layer and Components ................................................................ 15
1 LMG1205HBEVM Electrical Performance Specifications .............................................................. 7
2 Test Point Functional Descriptions....................................................................................... 10
3 List of Terminals............................................................................................................ 11
4 LMG1205HBEVM List of Materials ...................................................................................... 16
List of Figures
List of Tables
..................... 14
OUT
SNVU552–March 2017
Submit Documentation Feedback
List of Figures
3
WARNING
Preface
SNVU552–March 2017
General TI High Voltage Evaluation User Safety Guidelines
Always follow TI’s setup and application instructions, including use of all interface components within their recommended electrical rated voltage and power limits. Always use electrical safety precautions to help ensure your personal safety and the safety of those working around you. Contact TI’s Product Information Center http://support/ti./com for further information.
Save all warnings and instructions for future reference.
Failure to follow warnings and instructions may result in personal injury, property damage, or death due to electrical shock and/or burn hazards.
The term TI HV EVM refers to an electronic device typically provided as an open-framed, unenclosed printed-circuit board assembly. It is intended strictly for use in development laboratory environments, solely for qualified professional users having training, expertise, and knowledge of electrical safety risks in development and application of high-voltage electrical circuits. Any other use and/or application are strictly prohibited by Texas Instruments. If you are not suitably qualified, you should immediately stop from further use of the HV EVM.
• Work Area Safety: – Maintain a clean and orderly work area. – Qualified observer(s) must be present anytime circuits are energized. – Effective barriers and signage must be present in the area where the TI HV EVM and its interface
electronics are energized, indicating operation of accessible high voltages may be present, for the purpose of protecting inadvertent access.
– All interface circuits, power supplies, evaluation modules, instruments, meters, scopes and other
related apparatus used in a development environment exceeding 50 V
electrically located within a protected Emergency Power Off (EPO) protected power strip. – Use a stable and non-conductive work surface. – Use adequately insulated clamps and wires to attach measurement probes and instruments. No
freehand testing whenever possible.
• Electrical Safety: As a precautionary measure, it is always a good engineering practice to assume that the entire
EVM may have fully accessible and active high voltages.
– De-energize the TI HV EVM and all its inputs, outputs, and electrical loads before performing any
electrical or other diagnostic measurements. Confirm that TI HV EVM power has been safely de­energized.
– With the EVM confirmed de-energized, proceed with required electrical circuit configurations, wiring,
measurement equipment hook-ups and other application needs, while still assuming the EVM circuit and measuring instruments are electrically live.
– When EVM readiness is complete, energize the EVM as intended.
/75 VDC must be
RMS
WARNING: While the EVM is energized, never touch the EVM or its electrical circuits as they could be at high voltages capable of causing electrical shock hazard.
4
Preface
Submit Documentation Feedback
SNVU552–March 2017
www.ti.com
• Personal Safety:
• Limitation for Safe Use:
Safety and Precautions
The EVM is designed for professionals who have received the appropriate technical training, and is designed to operate from an AC power supply or a high-voltage DC supply. Please read this user guide and the safety-related documents that come with the EVM package before operating this EVM.
– Wear personal protective equipment, for example, latex gloves and/or safety glasses with side
shields or protect EVM in an adequate lucent plastic box with interlocks from accidental touch.
– EVMs are not to be used as all or part of a production unit.
CAUTION
Do not leave the EVM powered when unattended.
WARNING
Hot surface! Contact may cause burns. Do not touch!
WARNING
Hot surface! Contact may cause burns. Do not touch!
WARNING
High Voltage! Electric shock is possible when connecting board to live wire. Board should be handled with care by a professional.
For safety, use of isolated test equipment with overvoltage and overcurrent protection is highly recommended.
SNVU552–March 2017
Submit Documentation Feedback
General TI High Voltage Evaluation User Safety Guidelines
5
The LMG1205HBEVM is designed to evaluate the LMG1205 100-V half-bridge driver for enhancement­mode GaN FETs. The main circuit in this EVM consists of two Gallium Nitride (GaN) FETs connected in a half-bridge configuration, driven by an LMG1205.
This EVM guide describes correct operation and measurement of the EVM, as well as the EVM construction and typical performance. Additionally, setup instructions, including power up, are described to achieve DC-DC conversion at a certain regulation voltage. The EVM board is designed to accelerate the evaluation of the LMG1205.
This board is not intended to be used as a standalone product, but rather is intended for use to evaluate the switching performance of the LMG1205.
1 Description
The LMG1205HBEVM evaluation module is a small, easy-to-use power stage with an external PWM signal. The board can be configured as a buck converter, boost converter, or other converter topology using a half bridge.
Because this is an open-loop board with an external PWM signal, it is not intended for evaluation of transient response. This EVM can be used to evaluate the performance of the LMG1205 in a hard­switched converter to sample measurements such as efficiency, switching speed, and slew rate.
The EVM features an LMG1205 half-bridge driver coupled with two 100-V, 7-mΩ GaN FETs in a half­bridge configuration. The module can deliver up to 10 A of current if the application includes adequate thermal management (monitor case temperature and ensure adequate airflow is present, if required). The thermal management considerations include forced air, heat sink, and lower operating frequency to minimize the power dissipation in the module.
User's Guide
SNVU552–March 2017
Using the LMG1205HBEVM
GaN Half-Bridge Power Stage EVM
1.1 EVM Features
LMG1205HBEVM features include:
• Input voltage operates up to 80 VDC
• Optimized PCB layout minimizes gate and power loop inductances to mitigate ringing effects
• Single-input, onboard for PWM signal with 8-ns dead time
• Configurable onboard dead-time adjustment by simple resistance change
• Onboard LDO for generating 5-V VCC supply from a poorly regulated supply between 5.5 V and 10 V
• Convenient test points for DC and switching signal evaluation
• Kelvin sense capability for efficiency measurements for input and output voltage
High-voltage levels may be present on the evaluation module whenever it is energized. Proper precautions must be taken when working with the EVM.
6
Using the LMG1205HBEVM GaN Half-Bridge Power Stage EVM
CAUTION
Submit Documentation Feedback
SNVU552–March 2017
www.ti.com
1.2 Typical Applications
The LMG1205 is suited for use in high frequency DC-DC converters. It is simple to use and requires few external components. Typical applications include:
• High-speed, synchronous buck converters
• Class D amplifiers for audio
• 48-V point-of-load converters for industrial, computing, and telecom
2 EVM Kit Contents
The kit contains the following:
• Safety instructions
• LMG1205HBEVM PCB assembly
3 Electrical Performance Specifications
Table 1. LMG1205HBEVM Electrical Performance Specifications
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
V V V V I P f
BUS
OUT
IN
PWM
OUT
OUT
SW
Half-bridge input voltage Connected to drain of high-side FET 80 V Half-bridge output voltage Connected through inductor L1 to SW 80 V Input voltage for 5-V VDD LDO 5.5 10 V PWM input voltage 0 5 V Half-bridge output current 10 A Half-bridge output power LMG1205 and GaN FETs TJ≤ 125ºC 160 W Switching frequency 0.1 1 5 MHz
Description
SNVU552–March 2017
Submit Documentation Feedback
Using the LMG1205HBEVM GaN Half-Bridge Power Stage EVM
7
Loading...
+ 15 hidden pages
Buy Points How it Works FAQ Contact Us Questions and Suggestions Privacy Policy Cookie Policy Terms of Use