TPS54610EVM 6ĆAmp Externally Compensated SWIFT Regulator Evaluation Module User’s Guide August 2001 PMP PD & PS SLVU054
IMPORTANT NOTICE Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete.
EVM IMPORTANT NOTICE Texas Instruments (TI) provides the enclosed product(s) under the following conditions: This evaluation kit being sold by TI is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not considered by TI to be fit for commercial use.
EVM WARNINGS AND RESTRICTIONS It is important to operate this EVM within the specified input and output ranges described in the EVM User’s Guide. Exceeding the specified input range may cause unexpected operation and/or irreversible damage to the EVM. If there are questions concerning the input range, please contact a TI field representative prior to connecting the input power.
Trademarks Preface Read This First About This Manual This user’s guide describes the characteristics, operation, and use of the TPS54610 6-amp externally compensated SWIFT regulator evaluation module (EVM). The user’s guide includes a schematic diagram and bill of materials.
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Contents Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Performance Specification Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents Figures 1–1 2–1 2–2 2–3 2–4 2–5 2–6 2–7 2–8 2–9 2–10 2–11 2–12 2–13 2–14 2–15 3–1 3–2 3–3 3–4 4–1 viii Frequency Trimming Resistor Selection Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 Measured Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents Tables 1–1 1–2 4–1 Performance Specification Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 Output Voltage Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 TPS54610 EVM Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Chapter 1 Introduction This chapter contains background information for the TPS54610 and support documentation for the TPS54610 evaluation module. The EVM performance specifications are also given. Topic Page 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 1.2 Performance Specification Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 1.3 Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Background 1.1 Background The TPS54610 evaluation module (EVM) uses the TPS54610 synchronous buck regulator to provide a 3.3-V output over an input range of 4.0 V to 6.0 V and over a load range of 0 A to 6 A. The EVM is designed to be easily modified. Additional pads support multiple input and output capacitors, and the inductor pads are large to accommodate different inductors. A jumper is provided to allow the switching frequency to be easily changed from 350 kHz to 550 kHz.
Modifications 1.3 Modifications The TPS54610 EVM is designed to support numerous types of input capacitors, output capacitors, and inductors (see Top-Side Layout Figure 3–1, and EVM schematic Figure 4–1). C3 provides pads for a surface mount input capacitor, while the holes of C1 can be used for through-hole input capacitors. Similarly, C10 and C11 provide pads for surface-mount output capacitors, while the holes of C12 can be used for through-hole output capacitors.
Modifications Figure 1–1. Frequency Trimming Resistor Selection Graph 750 Switching Frequency – kHz 700 650 600 550 500 450 400 350 300 250 60 70 80 90 100 110 120 130 140 150 160 170 180 R – Resistance – kΩ Table 1–2. Output Voltage Programming 1-4 Output Voltage (V) R2 (kΩ) 0.9 1000 1.2 28.7 1.5 14.7 1.8 9.76 2.5 5.49 3.3 3.
Chapter 2 Test Setup and Results This chapter describes how to properly connect, setup, and use the TPS54610 EVM. It also presents the test results and covers efficiency, output voltage regulation, load transients, loop response, output ripple, input ripple, and start-up. Topic Page 2.1 Input/Output Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 2.2 Loop Characterization Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 2.
Input/Output Connections 2.1 Input/Output Connections The TPS54610 EVM has the following input/output connections: J1 (Vin and GND) and J3 (Vout and GND). A diagram showing the connection points is shown in Figure 2–1. Connect a power supply capable of supplying 6 A to J1 through a pair of 20 AWG wires. Connect the load to J3 through a pair of 16 AWG wires. Minimize wire lengths to reduce losses in the wires.
Loop Characterization Setup 2.2 Loop Characterization Setup The TPS54610 EVM contains a 49.9-Ω resistor (R6) in the feedback path for use in measuring the loop response. Test points on either side of R6 (TP4 and TP3) provide connection points for network analyzer signals. By injecting a small AC signal across R6, the loop gain and phase can be measured from one side of R6 to the other.
Thermal Performance Figure 2–3. Measured Board Losses 2.5 TA = 25°C Losses – W 2 FSW = 550 kHz 1.5 1 FSW = 350 kHz 0.5 0 0 1 2 3 4 IL – Load Current – A 5 6 2.4 Thermal Performance The junction temperature is plotted versus the load current with a 5-V input voltage and a 25°C ambient temperature in Figure 2–4. The case temperature is plotted in Figure 2–5.
Output Voltage Regulation Figure 2–5. Measured Case Temperature at 25°C Ambient 60 TA = 25°C Case Temperature – °C 50 40 FSW = 550 kHz FSW = 350 kHz 30 20 10 0 0 1 2 3 4 IL – Load Current – A 5 6 2.5 Output Voltage Regulation The output voltage load regulation with a 5-V input and a 25°C ambient temperature is shown in Figure 2–6. The output voltage line regulation is shown in Figure 2–7. Over the input voltage range of 4.0 V to 6.
Output Voltage Regulation Figure 2–7. Measured Line Regulation 1.002 TA = 25°C Output Voltage (Normalized to 5-V Input) 1.0015 1.001 IO = 6 A 1.0005 IO = 3 A 1 0.9995 0.999 0.9985 0.998 4 4.5 5 IL – Load Current – A 5.5 6 2.6 Load Transients The TPS54610 EVM response to load transients is shown in Figure 2–8.The load transient in Figure 2–8 transitions from 1 A to 5 A in 10 µs. The output voltage deviates approximately 50 mV from its average value as a result of these transients. Figure 2–8.
Output Voltage Regulation 2.7 Loop Characteristics The loop gain and phase for a 5.0-V input and a 6.0-A load are shown in Figure 2–9 and Figure 2–10. The loop crossover frequency is approximately 25 kHz, and the phase margin is approximately 75°. Figure 2–9. Measured Loop Gain 50 40 Loop Gain – dB 30 20 10 0 –10 –20 100 1000 10000 f – Frequency – Hz 100000 Figure 2–10.
Output Voltage Regulation 2.8 Output Voltage Ripple The output ripple voltage is plotted in Figure 2–11 for a switching frequency of 350 kHz and in Figure 2–12 for a switching frequency of 550 kHz. The SLVP192 has a typical output voltage ripple of less than 18 mVpp. Figure 2–11. Measured Output Voltage Ripple at 350-kHz Operation VO (AC) 10 mV/div VI = 5 V IO = 6 A 1 µs/div Figure 2–12.
Output Voltage Regulation 2.9 Input Ripple Voltage The input ripple voltage for a 6-A load is shown in Figure 2–13 with a switching frequency of 350 kHz and in Figure 2–14 with a switching frequency of 550 kHz. With a switching frequency of 550 kHz, the input ripple is approximately 200 mVpp. The input ripple voltage can be made lower by adding capacitance to the input. Figure 2–13. Measured Input Voltage Ripple at 350-kHz Operation VI (AC) 10O mV/div VI = 5 V IO = 6 A 1 µs/div Figure 2–14.
Start-up 2.10 Start-up The start-up voltage waveform of the TPS54610 EVM is shown in Figure 2–15. There is approximately a 12.8-ms delay after the input voltage rises above the 3.0-V start-up voltage threshold before the TPS54610 EVM output begins to rise. The output voltage then ramps to 3.3 V in 7.2 ms.
Chapter 3 Board Layout This chapter provides a description of the TPS 54610 EVM board layout and layer illustrations. Topic 3.1 Page Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Layout 3.1 Layout The top-side (component) layer for the TPS54610 EVM is shown in Figure 3–1. The input decoupling capacitor (C9), bias decoupling capacitor (C4), and bootstrap capacitor (C8) are all located as close to the IC as possible. In addition, the compensation components are also kept close to the IC. The compensation circuit ties to the output voltage at the point of regulation (TP4). All layers are shown on the following pages and resemble a layer stack-up encountered in a typical application.
Layout Figure 3–2.
Layout Figure 3–3.
Layout Figure 3–4.
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Chapter 4 Schematic and Bill of Materials The EVM schematic and bill of materials are presented in this chapter. Topic Page 4.1 Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2 4.2 Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-2 4 3 2 1 R7 10 kΩ + VIN TP7 C1 1 C3 220 µ F TP1 C4 0.1 µ F C2 0.047 µ F TP6 C5 68 pF JP1 R1 9.76 kΩ C6 6800 pF 1 R3 1 2 3 4 25 26 27 28 R2 3.74 kΩ C7 24 23 22 21 20 14 13 12 11 10 9 8 7 6 5 19 18 17 16 15 49.9 Ω C10 470 µ F 4V R6 TP3 1 C14 1 R8 L1 4.7 uH R5 0.047 µ F C8 TP2 C9 10 µ F 1.18 kΩ 10 kΩ 0.
Bill of Materials 4.2 Bill of Materials Table 4–1. TPS54610 EVM Bill of Materials Count Ref Des Description Size MFR Part Number — C1, C12 Open 0.394 2 C10, C11 Capacitor, POSCAP, 470 µF, 4 V, 40 mΩ, 20% 7343 (D) Sanyo 4TPB470M 1 C13 Capacitor, ceramic, 1000 pF, 25 V, X7R, 10% 603 Murata GRM39X7R102K25 C14 Open 603 2 C2, C8 Capacitor, ceramic, 0.
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