Using the TPS54386EVM User's Guide March 2008 Power Supply MAN SLUU286
Using the TPS54386EVM User's Guide Literature Number: SLUU286 March 2008
User's Guide SLUU286 – March 2008 A 12-V Input, 5.0-V and 3.3-V Output, 2-A Non-Synchronous Buck Converter 1 Introduction The TPS54386EVM evaluation module (EVM) is a dual non-synchronous buck converter providing fixed 5.0-V and 3.3-V output at up to 2 A each from a 12-V input bus. The EVM is designed to start up from a single supply, so no additional bias voltage is required for start-up. The module uses the TPS54386 Dual Non-Synchronous Buck Converter with Integral High-Side FET. 1.
www.ti.com TPS54386EVM Electrical Performance Specifications 2 TPS54386EVM Electrical Performance Specifications Table 1. Electrical Performance Specifications SYMBOL PARAMETER MIN TYP MAX UNITS Input Characterstics VIN Input coltage IIN Input current No load input current Input UVLO IOUT = min to max VIN_UVLO 9.6 12 13.2 V VIN = nom, IOUT = max - 1.6 2.0 A VIN = nom, IOUT = 0 A - 12 20 mA 4.0 4.2 4.4 V Output Characterstics VOUT1 Output voltage 1 VIN = nom, IOUT = nom 4.
www.ti.com Schematic Schematic + 3 Figure 1. TPS54386EVM Schematic Note: For reference only, see Table 3, List of Materials for specific values. SLUU286 – March 2008 Submit Documentation Feedback A 12-V Input, 5.0-V and 3.
www.ti.com Schematic 3.1 Sequencing Jump (JP3) The TPS54386EVM provides a 3-pin, 100-mil header and shunt for programming the TPS54386’s sequencing function. Placing the JP3 shunt in the left position connects the sequence pin to BP and sets the TPS54386 controller to sequence Channel 2 prior to Channel 1 when Enable 2 is activated.
www.ti.com Schematic 3.3.1 Input Voltage Monitoring (TP1 and TP2) TPS54386EVM provides two test points for measuring the voltage applied to the module. This allows the user to measure the actual module voltage without losses from input cables and connectors. All input voltage measurements should be made between TP1 and TP2. To use TP1 and TP2, connect a voltmeter positive terminal to TP1 and negative terminal to TP2. 3.3.
www.ti.com 4 Test Set Up 4 4 Test Set Up 4.1 Equipment 4.1.1 Voltage Source VIN: The input voltage source (VIN) should be a 0-15 V variable dc source capable of 5 ADC. Connect VIN to J1 as shown in Figure 3. 4.1.2 • • • • 4.1.3 Meters A1: 0-3 ADC, ammeter V1: VIN, 0-15 V voltmeter V2: VOUT1 0-6 V voltmeter V3: VOUT2 0-4 V voltmeter Loads LOAD1: The Output1 Load (LOAD1) should be an electronic constant current mode load capable of 0-2 ADC at 5.
www.ti.com 4 Test Set Up 4.2 Equipment Setup Shown in Figure 2 is the basic test set up recommended to evaluate the TPS54386EVM. Please note that although the return for J1, J2 and JP3 are the same system ground, the connections should remain separate as shown in Figure 2 4.2.1 Procedure 1. Working at an ESD workstation, make sure that any wrist straps, bootstraps or mats are connected referencing the user to earth ground before power is applied to the EVM.
www.ti.com 4 Test Set Up Metal Ground Barrel Probe Tip TP3 / TP18 TP4 / TP19 Tip and Barrel Vout ripple measurement Figure 3. Tip and Barrel Measurement Technique (output ripple measurement using TP3 and TP4 or TP18 and TP19) FAN + + - V3 LOAD1 5.0V @ 2A V2 + A1 - - - VVIN + V1 - LOAD2 3.3V @ 2A + + Isolation Transformer Figure 4. Control Loop Measurement Setup 10 A 12-V Input, 5.0-V and 3.
www.ti.com 4 Test Set Up 4.3 Start Up / Shut Down Procedure 1. 2. 3. 4. 5. 6. 4.4 Output Ripple Voltage Measurement Procedure 1. 2. 3. 4. 5. 6. 7. 4.5 Increase VIN from 0 V to 12 VDC. Vary LOAD1 from 0 – 2 ADC Vary LOAD2 from 0 – 2 ADC Vary VIN from 9.6 VDC to 13.2 VDC Decrease VIN to 0 VDC Decrease LOAD1 to 0 A. Increase VIN from 0 V to 12 VDC. Adjust LOAD1 to desired load between 0 ADC and 2 ADC. Adjust VIN to desired load between 9.6 VDC and 13.2 VDC.
www.ti.com TPS54386EVM Typical Performance Data and Characteristic Curves 5 TPS54386EVM Typical Performance Data and Characteristic Curves Figure 5 through Figure 9 present typical performance curves for the TPS54386EVM. Since actual performance data can be affected by measurement techniques and environmental variables, these curves are presented for reference and may differ from actual field measurements. 5.1 Efficiency EFFICIENCY(VOUT = 3.3 V) vs LOADCURRENT EFFICIENCY(VOUT = 5.
www.ti.com TPS54386EVM Typical Performance Data and Characteristic Curves 5.2 Line and Load Regulation EFFICIENCY(VOUT1 = 3.3 V) vs LOADCURRENT EFFICIENCY(VOUT2 = 5.0 V) vs LOADCURRENT 3.340 5.020 3.338 12.0 V 5.015 h - Efficiency - % h - Efficiency - % 3.335 3.333 3.330 9.6 V 3.328 13.2 V 9.6 V 12.0 V 5.010 13.2 V 5.005 3.325 3.323 5.000 3.320 0.10 0.48 0.86 1.24 ILOAD - Load Current - A 1.62 2.00 0.10 0.48 0.86 1.24 1.62 2.00 ILOAD - Load Current - A Figure 6.
www.ti.com TPS54386EVM Typical Performance Data and Characteristic Curves 5.4 Switch Node Figure 8. TPS54386EVM Switching Waveforms VIN = 12 V, IOUT = 2 A Ch1: TP9 (SW1), Ch2: TP12 (SW2) 5.5 Control Loop Bode Plot (low line, VIN = 8 V) GAIN/PHASE vs FREQUENCY(VOUT = 3.3 V, I OUT = 2 A) 100 GAIN/PHASE vs FREQUENCY(VOUT = 5.
www.ti.com EVM Assembly Drawings and Layout 6 EVM Assembly Drawings and Layout The following figures (Figure 10 through Figure 12) show the design of the TPS54386EVM printed circuit board. The EVM has been designed using a 4-Layer, 2-oz copper-clad circuit board 3.0” x 3.0” with all components in a 1.15” x 2.
www.ti.com EVM Assembly Drawings and Layout Figure 11. TPS54386EVM Top Copper (viewed from top) 16 A 12-V Input, 5.0-V and 3.
www.ti.com EVM Assembly Drawings and Layout Figure 12. TPS54386EVM Bottom Copper (x-ray view from top) SLUU286 – March 2008 Submit Documentation Feedback A 12-V Input, 5.0-V and 3.
www.ti.com List of Materials 7 List of Materials Table 3. TPS54386EVM List of Materials 18 QTY REF DES DESCRIPTION MFR PART NUMBER 1 C1 Capacitor, aluminum, 25 V, 20%, 100 µF, 0.328 x 0.390 inch Panasonic EEEFC1E101P 2 C10, C11 Capacitor, ceramic, 25 V, X5R, 20%, 10 µF, 1210 TDK C3216X5R1E106M 1 C12 Capacitor, ceramic, 10 V, X5R, 20%, 4.7 µF, 0805 Std Std 1 C15 Capacitor, ceramic, 25 V, X7R, 20%, 22 nF, 0603 Std Std 2 C2, C20 Capacitor, ceramic, 10 V, X7R, 20%, 0.
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