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SNVU664 – November 2019

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LMR33640EVM User's Guide

User's Guide

SNVU664 – November 2019

LMR33640EVM User's Guide

The Texas Instruments LMR33640EVM evaluation module (EVM) helps designers evaluate the operation
and performance of the LMR33640 buck regulator. The LMR33640 is an easy-to-use synchronous step-
down DC/DC converters capable of driving up to 4 A of load current from an input voltage of 3.8 V to 36 V.
The LMR33640EVM features a selectable output voltage of 3.3 V or 5 V and a switching frequency of
either 400 kHz. See the

LMR33640 SIMPLE SWITCHER 3.8-V to 36-V, 4-A Step-Down Converter Data

Sheet

for additional features, detailed description, and available options.

Table 1

shows the EVM configuration.

Table 1. Device and Package Configurations

EVM

DEVICE

FREQUENCY/OUTPUT

CURRENT

LMR33640EVM

LMR33640ADDA

400 kHz / 4 A

Figure 1. EVM Board Image

Summary of Contents for LMR33640

Page 1: ...synchronous step down DC DC converters capable of driving up to 4 A of load current from an input voltage of 3 8 V to 36 V The LMR33640EVM features a selectable output voltage of 3 3 V or 5 V and a switching frequency of either 400 kHz See the LMR33640 SIMPLE SWITCHER 3 8 V to 36 V 4 A Step Down Converter Data Sheet for additional features detailed description and available options Table 1 shows t...

Page 2: ... 1 2 EVM Board Connections 3 3 EVM Card Edge Connections 4 4 Jumper Locations 4 5 FRA Setup 5 6 Efficiency VIN 12 V VOUT 5 V ƒSW 400 KHz 6 7 Efficiency VIN 12 V VOUT 3 3V ƒSW 400 kHz 6 8 LMR33640EVM Schematic 7 9 Top View of EVM 8 10 EVM Top Copper Layer 8 11 EVM Mid Layer One 9 12 EVM Mid Layer Two 9 13 EVM Bottom Copper Layer 10 List of Tables 1 Device and Package Configurations 1 2 BOM for LMR3...

Page 3: ...e card edge connector can be used for connections See Figure 2 for the top of board connections and Figure 3 for the card edge connections The following are the functions of the connections VIN Input supply to EVM Connect to a suitable input supply See the LMR33640 SIMPLE SWITCHER 3 8 V to 36 V 4 A Step Down Converter Data Sheet for input supply requirements GND System ground VOUT Output of EVM Co...

Page 4: ...r allows the EN input to be connected to either ground OFF or VIN ON Remove this jumper to allow an external logic signal to control the EN function VOUT This jumper is used to select one of the two pre defined output voltages The 3 3V position provides a 3 3 V output while the 5V position provides a 5 V output Figure 4 Jumper Locations 1 2 Test Points VIN Input supply to EVM Connect to a suitable...

Page 5: ...ag output This test point is connected to VCC through a 20 kΩ resistor The power good function can be monitored at this test point A Connection for frequency response analyzer on bottom of board See Figure 5 Figure 5 FRA Setup 2 Operation Once the previously described connections are made and the appropriate jumpers are set the EVM is ready to use If external control of the EN input is desired rem...

Page 6: ...e can be programmed by changing the value of RFBB on the EVM In addition the values of the inductor and the output capacitance may also need to be changed See the LMR33640 SIMPLE SWITCHER 3 8 V to 36 V 4 A Step Down Converter Data Sheet for more information The EVM has been designed for maximum flexibility regarding component selection This allows the user to place preferred components such as the...

Page 7: ...www ti com Schematic 7 SNVU664 November 2019 Submit Documentation Feedback Copyright 2019 Texas Instruments Incorporated LMR33640EVM User s Guide 4 Schematic Figure 8 LMR33640EVM Schematic ...

Page 8: ...out www ti com 8 SNVU664 November 2019 Submit Documentation Feedback Copyright 2019 Texas Instruments Incorporated LMR33640EVM User s Guide 5 Board Layout Figure 9 Top View of EVM Figure 10 EVM Top Copper Layer ...

Page 9: ...ww ti com Board Layout 9 SNVU664 November 2019 Submit Documentation Feedback Copyright 2019 Texas Instruments Incorporated LMR33640EVM User s Guide Figure 11 EVM Mid Layer One Figure 12 EVM Mid Layer Two ...

Page 10: ...Board Layout www ti com 10 SNVU664 November 2019 Submit Documentation Feedback Copyright 2019 Texas Instruments Incorporated LMR33640EVM User s Guide Figure 13 EVM Bottom Copper Layer ...

Page 11: ...250AC 0 C10 Cff CAP CERM 10 pF 50 V 5 C0G NP0 0603 TDK CGA3E2NP01H100D080AA 0 J1 VIN Standard Banana Jack Uninsulated 8 9 mm Keystone 575 8 1 J2 GND Standard Banana Jack Uninsulated 8 9 mm Keystone 575 8 1 J5 VOUT Standard Banana Jack Uninsulated 8 9 mm Keystone 575 8 1 J3 VSEL Header 100 mil 3x1 Gold TH Samtec HTSW 103 07 G S 1 J4 EN Header 100 mil 3x1 Gold TH Samtec HTSW 103 07 G S 1 L1 L1 Induc...

Page 12: ...other than TI b the nonconformity resulted from User s design specifications or instructions for such EVMs or improper system design or c User has not paid on time Testing and other quality control techniques are used to the extent TI deems necessary TI does not test all parameters of each EVM User s claims against TI under this Section 2 are void if User fails to notify TI of any apparent defects...

Page 13: ... These limits are designed to provide reasonable protection against harmful interference in a residential installation This equipment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instructions may cause harmful interference to radio communications However there is no guarantee that interference will not occur in a particular installation...

Page 14: ...y for convenience and should be verified by User 1 Use EVMs in a shielded room or any other test facility as defined in the notification 173 issued by Ministry of Internal Affairs and Communications on March 28 2006 based on Sub section 1 1 of Article 6 of the Ministry s Rule for Enforcement of Radio Law of Japan 2 Use EVMs only after User obtains the license of Test Radio Station as provided in R...

Page 15: ... any interfaces electronic and or mechanical between the EVM and any human body are designed with suitable isolation and means to safely limit accessible leakage currents to minimize the risk of electrical shock hazard User assumes all responsibility and liability for any improper or unsafe handling or use of the EVM by User or its employees affiliates contractors or designees 4 4 User assumes all...

Page 16: ...OR DAMAGES ARE CLAIMED THE EXISTENCE OF MORE THAN ONE CLAIM SHALL NOT ENLARGE OR EXTEND THIS LIMIT 9 Return Policy Except as otherwise provided TI does not offer any refunds returns or exchanges Furthermore no return of EVM s will be accepted if the package has been opened and no return of the EVM s will be accepted if they are damaged or otherwise not in a resalable condition If User feels it has...

Page 17: ...se resources are subject to change without notice TI grants you permission to use these resources only for development of an application that uses the TI products described in the resource Other reproduction and display of these resources is prohibited No license is granted to any other TI intellectual property right or to any third party intellectual property right TI disclaims responsibility for...

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