background image

Time (100 µs/DIV)

V

OUT

 (10 V/DIV, 12 V to 0 V)

V

IN

 (10 V/DIV, 12 V to -20 V)

Gate Drive (10 V/DIV)

Operation

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3

Operation

3.1

Reverse Polarity Protection

A dynamic voltage pulse from +12V to -20V is applied at the VBAT_1 input of the LM74610-SQEVM.

Figure 3

shows when the input voltage (yellow) drops down to -20V, the output voltage (blue) does not go

negative, and therefore, the load is protected from dynamic reverse pulses at the input. The LM74610-Q1
reacts the negative voltage surge within 2

μ

sec and shuts down the MOSFET by pulling the gate voltage to

zero (green). The output slowly decays due to the large output capacitors and increased time constant.

Figure 3. Response to Reverse Polarity 12V to -20V

6

List of Tables

SNVU489 – October 2015

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Copyright © 2015, Texas Instruments Incorporated

Summary of Contents for LM74610-SQEVM

Page 1: ...LM74610 SQEVM User s Guide Literature Number SNVU489 October 2015 ...

Page 2: ...ription 4 2 2 Board Setup 5 3 Operation 6 3 1 Reverse Polarity Protection 6 3 2 Output Voltage 8 4 Board Layout 10 5 Schematic 12 6 Bill of Materials 13 2 Table of Contents SNVU489 October 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 3: ...dic body diode voltage drop at the output 8 6 The LM74610 SQEVM Output voltage waveform 9 7 Top Assembly Layer 10 8 Bottom Layer 11 9 LM74610 SQEVM Schematic 12 List of Tables 1 Device and Package Configurations 4 2 LM74610 SQ EVM Bill of Materials for Configuration 13 3 SNVU489 October 2015 List of Figures Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 4: ...al and electrical characteristics see the LM74610 Q1 Reverse Polarity Protection Smart Diode Controller Data Sheet LM74610 Table 1 Device and Package Configurations CONVERTER IC PACKAGE U1 LM74610 Q1 VSSOP 8 2 Setup This section describes the jumpers and connectors on the EVM as well and how to properly connect set up and use the LM74610 SQEVM Ensure the power supply is turned off while making con...

Page 5: ...tandby mode or the drain current is smaller than 1mA typical The tests outlined in this document 3A constant current as the load and 12V at the input VBAT_1 Make sure that the external power supply source for the input voltage is capable of providing enough current to the output load so that the output voltage can be obtained Once all connections to the LM74610 SQEVM are verified power can be appl...

Page 6: ...20V the output voltage blue does not go negative and therefore the load is protected from dynamic reverse pulses at the input The LM74610 Q1 reacts the negative voltage surge within 2μsec and shuts down the MOSFET by pulling the gate voltage to zero green The output slowly decays due to the large output capacitors and increased time constant Figure 3 Response to Reverse Polarity 12V to 20V 6 List ...

Page 7: ...s the load from negative voltages Figure 4 Response to Start Up Reverse Polarity Note Please note that the leakage current is 60uA typ This means that if you apply a voltage on the output you will see some voltage on input and this voltage will collapse if you draw more current than the leakage current The same applies for a reverse voltage applied on the input 7 SNVU489 October 2015 List of Table...

Page 8: ...rop at the output During the rest of the period of conduction the LM74610 Q1 will drive the gate of the MOSFET When the MOSFET is ON it provides a low resistive path for the drain current to flow and minimizes the power dissipation associated with forward conduction The power losses during the MOSFET ON state depend primarily on the RDSON of the selected MOSFET and load current The LM74610 Q1 oper...

Page 9: ...www ti com Operation Figure 6 The LM74610 SQEVM Output voltage waveform 9 SNVU489 October 2015 List of Tables Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 10: ...Board Layout www ti com 4 Board Layout Figure 7 Top Assembly Layer 10 List of Tables SNVU489 October 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 11: ...www ti com Board Layout Figure 8 Bottom Layer 11 SNVU489 October 2015 List of Tables Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 12: ...wever they are typically used to clamp the positive and negative voltage surges respectively The output capacitors are recommended to protect the immediate output voltage collapse as a result of line disturbance 12 List of Tables SNVU489 October 2015 Submit Documentation Feedback Copyright 2015 Texas Instruments Incorporated ...

Page 13: ...1 Diode TVS Uni 28 V 600 W SMB Diodes Inc SMBJ28A 13 F 1 D1_2 Diode TVS Uni 14 V 600 W SMB Diodes Inc SMBJ14A 13 F 3 DRV_1 P1 P2 NONE NONE 1 FET1_A MOSFET N CH 40 V 75 A Vishay SQJ422EP T1 GE3 PowerPAK_SO 8L Siliconix 2 GND J4 Standard Banana Jack Insulated Black Keystone 6092 2 J3 VBAT_1 Standard Banana Jack Insulated Red Keystone 6091 2 TP2 TP4 Test Point Multipurpose Black TH Keystone 5011 2 TP...

Page 14: ...ring the warranty period to the address designated by TI and that are determined by TI not to conform to such warranty If TI elects to repair or replace such EVM TI shall have a reasonable time to repair such EVM or provide replacements Repaired EVMs shall be warranted for the remainder of the original warranty period Replaced EVMs shall be warranted for a new full ninety 90 day warranty period 3 ...

Page 15: ... by Industry Canada to operate with the antenna types listed in the user guide with the maximum permissible gain and required antenna impedance for each antenna type indicated Antenna types not included in this list having a gain greater than the maximum gain indicated for that type are strictly prohibited for use with this device Concernant les EVMs avec antennes détachables Conformément à la rég...

Page 16: ... 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 even with the inputs and outputs kept within the specified allowable ranges some circuit components may have elevated case temperatures These components include but are not limited to linear regulators switching transistors pass transistors cu...

Page 17: ...F REMOVAL OR REINSTALLATION ANCILLARY COSTS TO THE PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES RETESTING OUTSIDE COMPUTER TIME LABOR COSTS LOSS OF GOODWILL LOSS OF PROFITS LOSS OF SAVINGS LOSS OF USE LOSS OF DATA OR BUSINESS INTERRUPTION NO CLAIM SUIT OR ACTION SHALL BE BROUGHT AGAINST TI MORE THAN ONE YEAR AFTER THE RELATED CAUSE OF ACTION HAS OCCURRED 8 2 Specific Limitations IN NO EVENT SHALL T...

Page 18: ...esponsible for compliance with all legal regulatory and safety related requirements concerning its products and any use of TI components in its applications notwithstanding any applications related information or support that may be provided by TI Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failur...

Page 19: ...Mouser Electronics Authorized Distributor Click to View Pricing Inventory Delivery Lifecycle Information Texas Instruments LM74610 SQEVM ...

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