TPS56428EVM-534

www.ti.com Table of Contents User’s Guide TPS56428 Buck Converter Evaluation Module User's Guide ABSTRACT This user's guide contains information for the TPS56428EVM-534 evaluation module as well as for the TPS56428. Included are the performance specifications, schematic, and the bill of materials of the TPS56428EVM-534. Table of Contents 1 Introduction.............................................................................................................................................................................2 2 Performance Specification Summary................................................................................................................................... 3 3 Modifications...........................................................................................................................................................................4 3.1 Output Voltage Setpoint..................................................................................................................................................... 4 3.2 Output Filter and Closed-Loop Response..........................................................................................................................4 4 Test Setup and Results.......................................................................................................................................................... 5 4.1 Input/Output Connections.................................................................................................................................................. 5 4.2 Start-Up Procedure............................................................................................................................................................ 5 4.3 Efficiency............................................................................................................................................................................5 4.4 Load Regulation................................................................................................................................................................. 6 4.5 Line Regulation.................................................................................................................................................................. 8 4.6 Load Transient Response.................................................................................................................................................. 8 4.7 Output Voltage Ripple........................................................................................................................................................ 9 4.8 Input Voltage Ripple......................................................................................................................................................... 10 4.9 Start-Up............................................................................................................................................................................ 11 4.10 Shut-Down..................................................................................................................................................................... 12 5 Board Layout.........................................................................................................................................................................13 5.1 Layout.............................................................................................................................................................................. 13 6 Schematic, Bill of Materials, and Reference...................................................................................................................... 15 6.1 Schematic........................................................................................................................................................................ 15 6.2 Bill of Materials.................................................................................................................................................................16 6.3 Reference.........................................................................................................................................................................16 7 Revision History................................................................................................................................................................... 16 Trademarks D-CAP2™ and Eco-mode™ are trademarks of Texas Instruments. All trademarks are the property of their respective owners. SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 1 Introduction www.ti.com 1 Introduction The TPS56428 is a single, adaptive on-time, D-CAP2™-mode, synchronous buck converter requiring a low external component count. The D-CAP2 control circuit is optimized for low-ESR output capacitors such as POSCAP, SP-CAP, or ceramic types and features fast transient response with no external compensation. The switching frequency is internally set at a nominal 650 kHz. Pulse skipping Eco-mode™ operation improves efficiency under light load conditions. The high-side and low-side switching MOSFETs are incorporated inside the TPS56428 package along with the gate-drive circuitry. The low drain-to-source on-resistance of the MOSFETs allows the TPS56428 to achieve high efficiencies and helps keep the junction temperature low at high-output currents. The TPS56428 dc/dc synchronous converter is designed to provide up to a 4-A output from an input voltage source of 4.5 V to 18 V. The output voltage range is from 0.6 V to 7 V. Rated input voltage and output current range for the evaluation module are given in Table 1-1. The TPS56428EVM-534 evaluation module circuit is a single, synchronous buck converter providing 1.2 V at 4 A from 4.5-V to 18-V input. This user’s guide describes the TPS56428EVM-534 performance. Table 1-1. Input Voltage and Output Current Summary 2 EVM Input Voltage Range Output Current Range TPS56428EVM-534 VIN = 4.5 V to 18 V 0 A to 4 A TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback www.ti.com Performance Specification Summary 2 Performance Specification Summary A summary of the TPS56428EVM-534 performance specifications is provided in Table 2-1. Specifications are given for an input voltage of VIN = 12 V and an output voltage of 1.2 V, unless otherwise noted. The ambient temperature is 25°C for all measurement, unless otherwise noted. Table 2-1. TPS56428EVM-534 Performance Specifications Summary Specifications Test Conditions Input voltage range (VIN) Min Typ Max 4.5 12 18 Output voltage Operating frequency VIN = 12 V, IO = 2 A Output current range 1.2 V kHz 0 4 IO = 2 A Load regulation VIN = 12 V Overcurrent limit VIN = 12 V, LO = 1.5 µH Output ripple voltage VIN = 12 V, IO = 4 A 10 Maximum efficiency VIN = 5 V, IO= 0.7 A 89.8 SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback V 650 Line regulation ±0.12 5.6 A % +0.9 /–0.1 4.8 Unit % 7.0 A mVPP % TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 3 Modifications www.ti.com 3 Modifications These evaluation modules are designed to provide access to the features of the TPS56428. Some modifications can be made to this module. 3.1 Output Voltage Setpoint To change the output voltage of the EVMs, it is necessary to change the value of resistor R1. Changing the value of R1 can change the output voltage above 0.765 V. The value of R1 for a specific output voltage can be calculated using Equation 1. For output voltage from 0.6 V to 7 V: æ R1 ö VO = 0.6 ´ ç 1+ ÷ è R2 ø (1) Table 3-1 lists the R1 values for some common output voltages. For higher output voltages of 1.8 V or above, a feed-forward capacitor (C4) may be required to improve phase margin. Pads for this component (C4) are provided on the printed-circuit board (PCB). Note that the resistor values given in Table 3-1 are standard values and not the exact value calculated using Equation 1. Table 3-1. Output Voltages Output Voltage (V) (1) C4 (pF)(1) R1 (kΩ) R2 (kΩ) Min Typ L1 (µH) Max Min C9 + C10 + C11 (µF) Typ Max Min Max 1 33.2 49.9 5 33 100 1.0 1.5 4.7 20 68 1.05 37.4 49.9 5 33 100 1.0 1.5 4.7 20 68 1.2 49.9 49.9 5 22 1.0 1.0 1.5 4.7 20 68 1.5 75.0 49.9 5 15 33 1.0 1.5 4.7 20 68 1.8 100 49.9 5 10 22 1.0 1.5 4.7 20 68 2.5 158 49.9 5 10 22 1.5 2.2 4.7 20 68 3.3 226 49.9 2 5 15 1.5 2.2 4.7 20 68 5 365 49.9 2 5 10 2.2 3.3 4.7 20 68 6.5 487 2 2 5 10 2.2 3.3 4.7 20 68 Optional 3.2 Output Filter and Closed-Loop Response The TPS56428 relies on the output filter characteristics to ensure stability of the control loop. The recommended output filter components for common output voltages are given in Table 3-1. It may be possible for other output filter component values to provide acceptable closed-loop characteristics. R3 and TP4 are provided for convenience in breaking the control loop and measuring the closed-loop response. 4 TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback www.ti.com Test Setup and Results 4 Test Setup and Results This section describes how to properly connect, set up, and use the TPS56428EVM-534. The section also includes test results typical for the evaluation modules and efficiency, output load regulation, output line regulation, load transient response, output voltage ripple, input voltage ripple, start-up, and switching frequency. 4.1 Input/Output Connections The TPS56428EVM-534 is provided with input and output connectors and test points as shown in Table 4-1. A power supply capable of supplying 2 A must be connected to J1 through a pair of 20-AWG wires. The load must be connected to J2 through a pair of 20-AWG wires. The maximum load current capability is 2 A. Wire lengths must be minimized to reduce losses in the wires. Test point TP1 provides a place to monitor the VIN input voltages with TP2 providing a convenient ground reference. TP8 is used to monitor the output voltage with TP9 as the ground reference. Table 4-1. Connection and Test Points Reference Designator Function J1 VIN (see Table 1-1 for VIN range) J2 VOUT, 1.2 V at 4-A maximum JP1 EN control. Connect EN to OFF to disable, connect EN to ON to enable TP1 VIN test point at VIN connector TP2 GND test point at VIN connector. TP3 EN test point TP4 Power good (PG) test point TP5 Switch node test point TP6 Analog ground test point TP7 Power ground test point TP8 Output voltage test point at VOUT connector TP9 Ground test point at VOUT connector 4.2 Start-Up Procedure 1. Ensure that the jumper at JP1 (Enable control) is set from EN to OFF. 2. Apply appropriate VIN voltage to VIN and PGND terminals at J1. 3. Move the jumper at JP1 (Enable control) to cover EN and ON. The EVM enables the output voltage. 4.3 Efficiency Figure 4-1 shows the efficiency for the TPS56428EVM-534 at an ambient temperature of 25°C. SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 5 Test Setup and Results www.ti.com 100 90 80 Efficiency - % 70 VIN = 12 V VIN = 5 V 60 50 40 30 20 10 0 0 0.5 1 1.5 2 2.5 3 3.5 4 Output Current - A C001 Figure 4-1. TPS56428EVM-534 Efficiency Figure 4-2 shows the efficiency at light loads for the TPS56428EVM-534 at an ambient temperature of 25°C. 100 90 VIN = 5 V 80 Efficiency - % 70 60 50 VIN = 12 V 40 30 20 10 0 0.001 0.01 0.1 1 10 Output Current - A C002 Figure 4-2. TPS56428EVM-534 Light-Load Efficiency 4.4 Load Regulation The load regulation for the TPS56428EVM-534 is shown in Figure 4-3. 6 TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback www.ti.com Test Setup and Results 1 0.8 0.6 Load Regulation - % 0.4 VIN = 12 V 0.2 0 VIN = 5 V -0.2 -0.4 -0.6 -0.8 -1 0 0.5 1 1.5 2 2.5 3 3.5 4 Output Current - A C003 Figure 4-3. TPS56428EVM-534 Load Regulation, VIN = 5 V and VIN = 12 V SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 7 Test Setup and Results www.ti.com 4.5 Line Regulation The line regulation for the TPS56428EVM-534 is shown in Figure 4-4. 0.5 0.4 0.3 Line Rgulation - % 0.2 IOUT = 2.0 A 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 4 6 8 10 12 14 16 18 Input Voltage - V C004 Figure 4-4. TPS56428EVM-534 Line Regulation 4.6 Load Transient Response The TPS56428EVM-534 response to load transient is shown in Figure 4-5. The current step is from 1.0 A to 3.0 A. Total peak-to-peak voltage variation is as shown. VOUT = 20 mV / div (ac coupled) IOUT = 1 A / div Load step = 1.0 - 3.0 A, slew rate = 500 mA / µsec Time = 200 µsec / div Figure 4-5. TPS56428EVM-534 Load Transient Response 8 TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback www.ti.com Test Setup and Results 4.7 Output Voltage Ripple The TPS56428EVM-534 output voltage ripple is shown in Figure 4-6. The output current is the rated full load of 4 A. VOUT = 20 mV / div (ac coupled) SW = 5 V / div Time = 1 µsec / div Figure 4-6. TPS56428EVM-534 Output Voltage Ripple (IOUT = 4 A) The TPS56428EVM-534 output voltage ripple is shown in Figure 4-7. The output current is 500 mA. VOUT = 20 mV / div (ac coupled) SW = 5 V / div Time = 1 µsec / div Figure 4-7. TPS56428EVM-534 Output Voltage Ripple (IOUT = 500 mA) SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 9 Test Setup and Results www.ti.com The TPS56428EVM-534 output voltage ripple is shown in Figure 4-8. The output current is 1 m A. VOUT = 20 mV / div (ac coupled) SW = 5 V / div Time = 2 msec / div Figure 4-8. TPS56428EVM-534 Output Voltage Ripple (IOUT = 1 mA) 4.8 Input Voltage Ripple The TPS56428EVM-534 input voltage ripple is shown in Figure 4-9. The output current is the rated full load of 4 A. VIN = 50 mV / div (ac coupled) SW = 5 V / div Time = 1 µsec / div Figure 4-9. TPS56428EVM-534 Input Voltage Ripple 10 TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback www.ti.com Test Setup and Results 4.9 Start-Up The TPS56428EVM-534 start-up waveforms relative to VIN and EN are shown in Figure 4-10 and Figure 4-11. RLOAD = 1 Ω. VIN = 10 V / div VREG5 = 5 V / div PG = 5 V / div VOUT = 1 V / div Time = 2 msec / div Figure 4-10. TPS56428EVM-534 Start-Up Relative to VIN with VREG5, PG and VOUT EN = 10 V / div VREG5 = 5 V / div PG = 5 V / div VOUT = 1 V / div Time = 2 msec / div Figure 4-11. TPS56428EVM-534 Start-Up Relative to EN with VREG5, PG and VOUT SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 11 Test Setup and Results www.ti.com 4.10 Shut-Down The TPS56428EVM-534 shut-down waveforms relative to VIN and EN are shown in Figure 4-12 and Figure 4-13. RLOAD = 1 Ω. VIN = 10 V / div VREG5 = 5 V / div PG = 5 V / div VOUT = 1 V / div Time = 2 msec / div Figure 4-12. TPS56428EVM-534 Shut-Down Relative to VIN with VREG5, PG and VOUT EN = 10 V / div VREG5 = 5 V / div PG = 5 V / div VOUT = 1 V / div Time = 2 msec / div Figure 4-13. TPS56428EVM-534 Shut-Down Relative to EN with VREG5, PG and VOUT 12 TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback www.ti.com Board Layout 5 Board Layout This section provides description of the TPS56428EVM-534, board layout, and layer illustrations. 5.1 Layout The board layout for the TPS56428EVM-534 is shown in Figure 5-1 through Figure 5-5. The top layer contains the main power traces for VIN, VOUT, and ground. Also on the top layer are connections for the pins of the TPS56428 and a large area filled with ground. Many of the signal traces also are located on the top side. The input decoupling capacitors are located as close to the IC as possible. The input and output connectors, test points, and all of the components are located on the top side. Internal layer 1, Internal layer 2 and the bottom layer are predominantly power ground planes. An analog ground (AGND) area is provided on internal layer 1. Analog ground (AGND) and power ground (PGND) are connected at a single point on the internal layer 1 as shown. Internal layer 2 contains an additional VIN area as well as a connection to the VIN pin of the EN control jumper JP1. The bottom layer contains the output voltage feedback trace. Figure 5-1. Top Assembly Figure 5-2. Top Layer SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 13 Board Layout www.ti.com Figure 5-3. Internal Layer 1 Figure 5-4. Internal Layer 2 Figure 5-5. Bottom Layer 14 TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback www.ti.com Schematic, Bill of Materials, and Reference 6 Schematic, Bill of Materials, and Reference 6.1 Schematic Figure 6-1 is the schematic for the TPS56428EVM-534. TP1 J1 VIN = 4.5 - 18 V 1 2 JP1 TP2 ON EN OFF 3 2 1 C1 C2 C3 10µF 10µF 0.1µF R4 10.0k PGND TP3 PGND 1 R3 0 U1 TPS56428 AGND R1 2 EN VIN VFB VBST 8 TP5 7 49.9k C7 TP4 R5 open 4 VREG5 PG SW 6 TP8 L1 0.1µF 3 C4 PWR PAD VIN GND 1 VOUT = 1.2 V, IOUT = 4 A 2 PGND 5 C8 open C10 C11 22µF 22µF open VOUT GND TP9 9 100k C9 J2 1 2 1.5µH R2 49.9k AGND C5 C6 0.47µF open R6 TP6 NT1 open PGND PGND AGND TP7 PGND Net-Tie PGND AGND PGND PGND Figure 6-1. TPS56428EVM-534 Schematic Diagram SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated 15 Schematic, Bill of Materials, and Reference www.ti.com 6.2 Bill of Materials Table 6-1. Bill of Materials Designator Qty PCB 1 C1, C2 2 C3, C7 2 C4, C6, C8 0 C5 1 C9, C10 2 C11 Value Description Package Reference Part Number Manufacturer Printed Circuit Board 2.00" x 2.50" PWR534A Any 10uF CAP, CERM, 10uF, 35V, +10/%, X7R, 1210 1210 GRM32ER7YA106KA12L MuRata 0.1uF CAP, CERM, 0.1uF, 50V, +10/%, X7R, 0603 0603 GRM188R71H104KA93D MuRata CAP, CERM, xxxF, xxV, [TempCo], xx%, 0603 0603 0.47uF CAP, CERM, 0.47uF, 25V, +10/%, X5R, 0603 0603 GRM188R61E474KA12D MuRata 22uF CAP, CERM, 22uF, 10V, +10/%, X5R, 1206 1206 GRM31CR61A226KE19L MuRata 0 CAP, CERM, xxxF, xxV, [TempCo], xx%, 1206 1206 FID1, FID2, FID3 0 Fiducial mark. There is nothing to buy or mount. Fiducial N/A N/A J1, J2 2 2x1 Conn Term Block, 2POS, 3.81mm, TH PhoenixConact_1727010 1727010 Phoenix Contact JP1 1 1x3 Header, TH, 100mil, 1x3, Gold plated, 230 mil above insulator PBC03SAAN PBC03SAAN Sullins Connector Solutions L1 1 1.5µH Inductor, SMT, 11A, 9.7 milliohm 0.256 x 0.280 inch SPM6530-1R5M100 TDK LBL1 1 Thermal Transfer Printable Labels, 1.25" W x 0.25" H 10,000 per roll PCB Label 1.25"H x 0.25"W THT-13-457-10 Brady R1, R2 2 49.9k RES, 49.9k ohm, 1%, 0.1W, 0603 0603 CRCW060349K9FKEA Vishay-Dale R3 1 0 RES, 0 ohm, 5%, 0.1W, 0603 0603 MCR03EZPJ000 Rohm R4 1 10.0k RES, 10.0k ohm, 1%, 0.1W, 0603 0603 CRCW060310K0FKEA Vishay-Dale R5 1 100k RES, 100k ohm, 1%, 0.1W, 0603 0603 CRCW0603100KFKEA Vishay-Dale R6 0 RES, xxx ohm, x%, xW, 0603 0603 SH-JP1 1 1x2 Shunt, 100mil, Gold plated, Black Shunt 969102-0000-DA 3M TP1, TP5, TP8 3 Red Test Point, TH, Multipurpose, Red Keystone5010 5010 Keystone TP2, TP6, TP7, TP9 4 Black Test Point, TH, Multipurpose, Black Keystone5011 5011 Keystone TP3, TP4 2 White Test Point, TH, Multipurpose, White Keystone5012 5012 Keystone U1 1 DC-DC Converter, 4.5 - 18 Vin, 4A SOP8 TPS56428DDA Texas Instruments 6.3 Reference 1. TPS56428, 4.5-V to 18-V Input, 4-A Synchronous Step-Down SWIFT™ Converter data sheet (SLVSBV4) 7 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision * (March 2013) to Revision A (June 2021) Page • Updated user's guide title................................................................................................................................... 2 • Updated the numbering format for tables, figures, and cross-references throughout the document. ................2 16 TPS56428 Buck Converter Evaluation Module User's Guide Copyright © 2022 Texas Instruments Incorporated SLVU892A – MARCH 2013 – REVISED JUNE 2021 Submit Document Feedback IMPORTANT NOTICE AND DISCLAIMER TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS” AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY RIGHTS. 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