TPS54231EVM-372

www.ti.com Table of Contents User’s Guide TPS54231 Step-Down Converter Evaluation Module User's Guide Table of Contents 1 Introduction.............................................................................................................................................................................2 1.1 Background........................................................................................................................................................................ 2 1.2 Performance Specification Summary.................................................................................................................................2 1.3 Modifications...................................................................................................................................................................... 3 2 Test Setup and Results.......................................................................................................................................................... 3 2.1 Input / Output Connections................................................................................................................................................ 3 2.2 Efficiency............................................................................................................................................................................4 2.3 Output Voltage Load Regulation........................................................................................................................................ 5 2.4 Output Voltage Line Regulation......................................................................................................................................... 6 2.5 Load Transients..................................................................................................................................................................6 2.6 Loop Characteristics.......................................................................................................................................................... 7 2.7 Output Voltage Ripple........................................................................................................................................................ 7 2.8 Input Voltage Ripple........................................................................................................................................................... 8 2.9 Powering Up.......................................................................................................................................................................8 2.10 Eco-mode Operation........................................................................................................................................................ 9 2.11 Thermal Characteristics....................................................................................................................................................9 3 Board Layout......................................................................................................................................................................... 11 3.1 Layout...............................................................................................................................................................................11 3.2 Estimated Circuit Area..................................................................................................................................................... 12 4 Schematic and Bill of Materials...........................................................................................................................................13 4.1 Schematic........................................................................................................................................................................ 13 4.2 Bill of Materials.................................................................................................................................................................14 5 Revision History................................................................................................................................................................... 15 List of Figures Figure 2-1. TPS54231EVM-372 Efficiency.................................................................................................................................. 4 Figure 2-2. TPS54231EVM-372 Low Current Efficiency..............................................................................................................5 Figure 2-3. TPS54231EVM-372 Load Regulation....................................................................................................................... 5 Figure 2-4. TPS54231EVM-372 Line Regulation........................................................................................................................ 6 Figure 2-5. TPS54231EVM-372 Transient Response................................................................................................................. 6 Figure 2-6. TPS54231EVM-372 Loop Response........................................................................................................................ 7 Figure 2-7. TPS54231EVM-372 Output Ripple........................................................................................................................... 7 Figure 2-8. TPS54231EVM-372 Input Ripple.............................................................................................................................. 8 Figure 2-9. TPS54231EVM-372 Start-Up Relative to VIN ........................................................................................................... 8 Figure 2-10. TPS54231EVM-372 Start-up Relative to Enable.................................................................................................... 9 Figure 2-11. TPS54231EVM–372 Eco–mode Operation............................................................................................................. 9 Figure 2-12. TPS54231EVM-372 Thermal Image..................................................................................................................... 10 Figure 3-1. TPS54231EVM-372 Top-Side Layout......................................................................................................................11 Figure 3-2. TPS54231EVM-372 Bottom-Side Layout................................................................................................................12 Figure 3-3. TPS54231EVM-372 Top-Side Assembly.................................................................................................................12 Figure 4-1. TPS54231EVM-372 Schematic...............................................................................................................................14 List of Tables Table 1-1. Input Voltage and Output Current Summary...............................................................................................................2 Table 1-2. TPS54231EVM-372 Performance Specification Summary.........................................................................................2 Table 1-3. Output Voltages Available...........................................................................................................................................3 Table 2-1. EVM Connectors and Test Points............................................................................................................................... 4 Table 4-1. TPS54231EVM-372 Bill of Materials.........................................................................................................................15 SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 1 Trademarks www.ti.com Trademarks All trademarks are the property of their respective owners. 1 Introduction This user's guide contains background information for the TPS54231 as well as support documentation for the TPS54231EVM-372 evaluation module (HPA372). Also included are the performance specifications, the schematic, and the bill of materials for the TPS54231EVM-372. 1.1 Background The TPS54231 dc/dc converter is designed to provide up to a 2 A output from an input voltage source of 3.5 V to 28 V. Rated input voltage and output current range for the evaluation module are given in Table 1-1. This evaluation module is designed to demonstrate the small printed-circuit-board areas that may be achieved when designing with the TPS54231 regulator. The switching frequency is internally set at a nominal 570 kHz. The high-side MOSFET is incorporated inside the TPS54231 package along with the gate drive circuitry. The low drain-to-source on resistance of the MOSFET allows the TPS54231 to achieve high efficiencies and helps keep the junction temperature low at high output currents. The compensation components are external to the integrated circuit (IC), and an external divider allows for an adjustable output voltage. Additionally, the TPS54231 provides adjustable slow start and undervoltage lockout inputs. The absolute maximum input voltage is 30 V for the TPS54231EVM-372. Table 1-1. Input Voltage and Output Current Summary EVM INPUT VOLTAGE RANGE OUTPUT CURRENT RANGE TPS54231EVM-372 VIN = 7 V to 28 V 0 A to 2 A 1.2 Performance Specification Summary A summary of the TPS54231EVM-372 performance specifications is provided in Table 1-2. Specifications are given for an input voltage of VIN = 15 V and an output voltage of 3.3 V, unless otherwise specified. The TPS54231EVM-372 is designed and tested for VIN = 7 V to 28 V. The ambient temperature is 25°C for all measurements, unless otherwise noted. Table 1-2. TPS54231EVM-372 Performance Specification Summary SPECIFICATION TEST CONDITIONS VIN voltage range MIN 7 Output voltage set point MAX 15 28 3.3 Output current range VIN = 7 V to 28 V Line regulation IO = 1 A, VIN = 7 V to 28 V ±0.15% Load regulation VIN = 15 V, IO = 0 A to 2 A ±0.15% Load transient response IO = 0.5 A to 1.5 A IO = 1.5 A to 0.5 A 0 UNIT V V 2 A Voltage change –100 Recovery time 150 μs Voltage change 100 mV Recovery time 150 μs mV Loop bandwidth VIN = 15 V, IO = 1 A 27 kHz Phase margin VIN = 15 V , IO = 1 A 55 ° Input ripple voltage IO = 2 A 125 mVpp Output ripple voltage IO = 2 A 5 mVpp Output rise time Operating frequency Maximum efficiency 2 TYP TPS54231EVM-372, VIN = 7 V, IO = 0.5 A TPS54231 Step-Down Converter Evaluation Module User's Guide 6 ms 570 kHz 92.7% SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated www.ti.com Introduction 1.3 Modifications These evaluation modules are designed to provide access to the features of the TPS54231. Some modifications can be made to this module. 1.3.1 Output Voltage Set Point To change the output voltage of the EVM, it is necessary to change the value of resistor R6. Changing the value of R6 can change the output voltage above 0.8 V. The value of R6 for a specific output voltage can be calculated using Equation 1. R 6 = 10.2 k W ´ 0.8 V VOUT - 0.8 V (1) Table 1-3 lists the R6 values for some common output voltages. Note that VIN must be in a range so that the minimum on-time is greater than 130 ns, and the maximum duty cycle is less than 91%. The values given in Table 1-3 are standard values, not the exact value calculated using Equation 1. Table 1-3. Output Voltages Available Output Voltage (V) R6 Value (kΩ) 1.8 8.25 2.5 4.75 3.3 3.24 5 1.96 2 Test Setup and Results This section describes how to properly connect, set up, and use the TPS54231EVM-372 evaluation module. The section also includes test results typical for the evaluation module and covers efficiency, output voltage regulation, load transients, loop response, output ripple, input ripple, and start-up. 2.1 Input / Output Connections The TPS54231EVM-372 is provided with input/output connectors and test points as shown in Table 2-1. 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 J4 through a pair of 20 AWG wires. The maximum load current capability must be 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. TP5 is used to monitor the output voltage with TP6 as the ground reference. SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 3 Test Setup and Results www.ti.com Table 2-1. EVM Connectors and Test Points Reference Designator Function J1 VIN (see Table 1-1 for VIN range) J2 2-pin header for enable. Connect EN to ground to disable, open to enable. J3 2-pin header for slow start monitor and GND. J4 VOUT, 3.3 V at 2 A maximum TP1 VIN test point at VIN connector TP2 GND test point at VIN TP3 PH test point TP4 Test point between voltage divider network and output. Used for loop response measurements. TP5 Output voltage test point at OUT connector TP6 GND test point at OUT connector 2.2 Efficiency The efficiency of this EVM peaks at a load current of about 0.5 A - 1 A and then decreases as the load current increases towards full load. Figure 2-1 shows the efficiency for the TPS54231EVM-372 at an ambient temperature of 25°C. 100% VIN = 7 V 90% 80% Efficiency - % 70% VIN = 24 V VIN = 28 V 60% VIN = 15 V 50% 40% 30% 20% 10% 0% 0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 Output Current(A) - IO Figure 2-1. TPS54231EVM-372 Efficiency Figure 2-2 shows the efficiency for the TPS54231EVM-372 at lower output currents between 0.02 A and 0.20 A at an ambient temperature of 25°C. 4 TPS54231 Step-Down Converter Evaluation Module User's Guide SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated www.ti.com Test Setup and Results 100% VIN = 7 V VIN = 15 V 90% 80% Efficiency - % 70% 60% VIN = 28 V VIN = 24 V 0.10 0.14 50% 40% 30% 20% 10% 0% 0.00 0.02 0.04 0.06 0.08 0.12 0.16 0.18 0.20 Output Current (IO) - A Figure 2-2. TPS54231EVM-372 Low Current Efficiency The efficiency may be lower at higher ambient temperatures, due to temperature variation in the drain-to-source resistance of the internal MOSFET. 2.3 Output Voltage Load Regulation The load regulation for the TPS54231EVM-372 is shown in Figure 2-3. 0.20% % Regulation Output Output Regulation- (%) 0.15% 0.10% VIN = 7 V VIN = 24 V VIN = 15 V 0.05% 0.00% -0.05% VIN = 28 V -0.10% 0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 Output Current Output Current (IO)(A) -A Figure 2-3. TPS54231EVM-372 Load Regulation Measurements are given for an ambient temperature of 25°C. SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 5 Test Setup and Results www.ti.com 2.4 Output Voltage Line Regulation The line regulation for the TPS54231EVM-372 is shown in Figure 2-4. 0.15% Output Regulation - % 0.10% 0.05% IO = 1 A 0.00% IO = 2 A -0.05% IO = 0 A -0.10% 5.00 10.00 15.00 20.00 25.00 30.00 Input Voltage (VIN) - V Figure 2-4. TPS54231EVM-372 Line Regulation 2.5 Load Transients The TPS54231EVM-372 response to load transients is shown in Figure 2-5. The current step is from 25% to 75% of maximum rated load at 15V input. Total peak-to-peak voltage variation is as shown, including ripple and noise on the output. Figure 2-5. TPS54231EVM-372 Transient Response 6 TPS54231 Step-Down Converter Evaluation Module User's Guide SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated www.ti.com Test Setup and Results 2.6 Loop Characteristics The TPS54231EVM-372 loop-response characteristics are shown in Figure 2-6 . Gain and phase plots are shown for VIN voltage of 15 V. Load current for the measurement is 1 A. 60 160 50 Gain 110 Gain - dB 30 20 60 Phase 10 Phase(°) - deg 40 10 0 -10 -40 -20 -30 -90 10 100 1k 10k 100k 1M Frequency(f) - Hz Figure 2-6. TPS54231EVM-372 Loop Response 2.7 Output Voltage Ripple The TPS54231EVM-372 output voltage ripple is shown in Figure 2-7. The output current is the rated full load of 2 A and VIN = 15 V. The ripple voltage is measured directly across the output capacitors. Figure 2-7. TPS54231EVM-372 Output Ripple SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 7 Test Setup and Results www.ti.com 2.8 Input Voltage Ripple The TPS54231EVM-372 input voltage ripple is shown in Figure 2-8 . The output current is the rated full load of 2 A and VIN = 15 V. The ripple voltage is measured directly across the input capacitors. Figure 2-8. TPS54231EVM-372 Input Ripple 2.9 Powering Up The start-up waveforms are shown in Figure 2-9 and Figure 2-10. In Figure 2-9, the top trace shows VIN, and the bottom trace shows VOUT. In Figure 2-10 , the top trace shows EN (enable) whereas the bottom trace shows VOUT. In Figure 2-10, the input voltage is initially applied and the output is inhibited by using a jumper at J2 to tie EN to GND. When the jumper is removed, EN is released. When the EN voltage reaches the enable-threshold voltage of 1.25 V, the start-up sequence begins and the internal reference voltage begins to ramp up at the internally set rate toward 0.8 V and the output voltage ramps up to the externally set value of 3.3 V. The input voltage for these plots is 15 V and there is no load. Figure 2-9. TPS54231EVM-372 Start-Up Relative to VIN 8 TPS54231 Step-Down Converter Evaluation Module User's Guide SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated www.ti.com Test Setup and Results Figure 2-10. TPS54231EVM-372 Start-up Relative to Enable 2.10 Eco-mode Operation At light load currents, the TPS54231 is designed to operate in pulse skipping Eco-mode. When the peak inductor current is lower than 100 mA typical, the device enters Eco-mode. Figure 2-11 shows Eco-mode operation, channel 1(C1) shows the output voltage while channel 2(C2) shows the switching node (PH). Figure 2-11. TPS54231EVM–372 Eco–mode Operation 2.11 Thermal Characteristics This section shows a thermal image of the TPS54231EVM-372 running at 28 V input and 2 A load. These are the worst case conditions for maximum power loss. There is no air flow and the ambient temperature is 25°C. The peak temperature of the IC (85.8°C) is well below the maximum recommended operating condition listed in the datasheet of 150°C. SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 9 Test Setup and Results www.ti.com Figure 2-12. TPS54231EVM-372 Thermal Image 10 TPS54231 Step-Down Converter Evaluation Module User's Guide SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated www.ti.com Board Layout 3 Board Layout This section provides a description of the TPS54231EVM-372, board layout, and layer illustrations. 3.1 Layout The board layout for the TPS54231EVM-372 is shown in Figure 3-1 through Figure 3-3. The topside layer of the EVM is laid out in a manner typical of a user application. The top and bottom layers are 2-oz. copper. The top layer contains the main power traces for VIN, VOUT, and VPHASE. Also on the top layer are connections for the remaining pins of the TPS54231 and a large area filled with ground. The bottom layer contains ground and a signal route for the BOOT capacitor. The top and bottom and internal ground traces are connected with multiple vias placed around the board including ten vias directly under the TPS54231 device to provide a thermal path from the top-side ground plane to the bottom-side ground plane. The input decoupling capacitors (C1, C2, and C3) and bootstrap capacitor (C4) are all located as close to the IC as possible. In addition, the voltage set-point resistor divider components are also kept close to the IC. The voltage divider network ties to the output voltage at the point of regulation, the copper VOUT trace past the output capacitor C10. For the TPS54231, an additional input bulk capacitor may be required, depending on the EVM connection to the input supply. Figure 3-1. TPS54231EVM-372 Top-Side Layout SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 11 Board Layout www.ti.com Figure 3-2. TPS54231EVM-372 Bottom-Side Layout Figure 3-3. TPS54231EVM-372 Top-Side Assembly 3.2 Estimated Circuit Area The estimated printed circuit board area for the components used in this design is 0.68 in2. This area does not include test point or connectors. 12 TPS54231 Step-Down Converter Evaluation Module User's Guide SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated www.ti.com Schematic and Bill of Materials 4 Schematic and Bill of Materials This section presents the TPS54231EVM-372 schematic and bill of materials. 4.1 Schematic Figure 4-1 is the schematic for the TPS54231EVM-372. SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 13 www.ti.com + Schematic and Bill of Materials Figure 4-1. TPS54231EVM-372 Schematic 4.2 Bill of Materials Table 4-1 presents the bill of materials for the TPS54231EVM-372. 14 TPS54231 Step-Down Converter Evaluation Module User's Guide SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated www.ti.com Revision History Table 4-1. TPS54231EVM-372 Bill of Materials Count RefDes Value 2 C1, C2 4.7 μF 0 C10 Open 1 C3 0.01 μF 1 C4 0.1 μF 1 C5 1 C6 1 2 Description Part Number MFR 1210 Std Std 7343(D) Std Std Capacitor, Ceramic, 50V, X7R, 10% 0603 Std Std Capacitor, Ceramic, 16V, X7R, 10% 0603 Std Std 0.015 μF Capacitor, Ceramic, 16V, X7R, 10% 0603 Std Std 1000 pF Capacitor, Ceramic, 16V, X7R, 10% 0603 Std Std C7 47 pF Capacitor, Ceramic, 16V, X7R, 10% 0603 Std Std C8, C9 47 μF Capacitor, Ceramic, 6.3, X5R, 20% 1206 C3216X5R0J476MT TDK 1 D1 B240A Diode, Schottky, 2A, 40V SMA B240A Diodes Inc 2 J1, J4 ED1514 Terminal Block, 2-pin, 6-A, 3.5mm 0.27 × 0.25 inch ED1514 OST 2 J2, J3 PTC36SAAN Header, 2-pin, 100mil spacing, (36-pin strip) 0.100 × 2 PTC36SAAN Sullins 10 μH Inductor, SMT, 3.9A, 35 mΩ 0.402 × 0.394 inch MSS1038-103NL Coilcraft 1 L1 Capacitor, Ceramic, 50V, X7R, 20% Size 1 R1 332k Resistor, Chip, 1/16W, 1% 0603 Std Std 1 R2 68.1k Resistor, Chip, 1/16W, 1% 0603 Std Std 1 R3 29.4k Resistor, Chip, 1/16W, 1% 0603 Std Std 1 R4 0 Resistor, Chip, 1/16W, 1% 0603 Std Std 1 R5 10.2k Resistor, Chip, 1/16W, 1% 0603 Std Std 1 R6 3.24k Resistor, Chip, 1/16W, 1% 0603 Std Std 0 R7 Open Resistor, Chip, 1/16W, 1% 0603 Std Std 3 TP1, TP3, TP5 5000 Test Point, Red, Thru Hole Color Keyed 0.100 × 0.100 inch 5000 Keystone 3 TP2, TP4, TP6 5001 Test Point, Black, Thru Hole Color Keyed 0.100 × 0.100 inch 5001 Keystone 1 U1 TPS54231D IC, DC-DC Converter, 28V, 2A SO-8 TPS54231D TI 1 — PCB 2.0" x 2.0" x 0.062" HPA372 Any 1 — Shunt, 100-mil, Black 0.100 929950-00 3M 5 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision * (August 2008) to Revision A (October 2021) Page • Updated the numbering format for tables, figures, and cross-references throughout the document. ................2 • Updated the user's guide title............................................................................................................................. 2 SLVU263A – AUGUST 2008 – REVISED OCTOBER 2021 TPS54231 Step-Down Converter Evaluation Module User's Guide Submit Document Feedback Copyright © 2022 Texas Instruments Incorporated 15 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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