A 600-W, Isolated PFC Power Supply for AVR Amplifiers Based on the TAS5630 and TAS5631 User's Guide Literature Number: SLOU293C June 2010 – Revised September 2012
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User's Guide SLOU293C – June 2010 – Revised September 2012 A 600-W, Isolated PFC Power Supply for AVR Amplifiers Based on the TAS5630 and TAS5631 This user guide documents a low-profile power supply that is suitable for AVR amplifiers or other high power amplifier applications. The power supply accepts an ac line-input voltage (108 VRMS to 265 VRMS), and produces an output voltage of 50-VDC for loads up to 12 A (600 W).
Scope www.ti.com The requirements for a modern AVR include a slim physical profile and the ability to operate from the acline input at close to unity power factor. Therefore, an AVR application demands the power supply be of low height, and comply with the power quality requirements defined in the IEC standard, 61000-3-2. In addition, the combination of a tight physical package and the desire to meet Energy Star™ guidelines requires that the design also demonstrates high efficiency.
Electrical Performance 3 www.ti.com Electrical Performance Table 1. Electrical Performance (1) (2) (3) PARAMETER CONDITIONS MIN TYP MAX UNITS INPUT CHARACTERISTIC VI Input Voltage F Line frequency II Input current p.f. Power factor 108 265 48 65 Vrms Hz 8 Arms 0.
Overall System Description www.ti.com 4 Overall System Description 4.1 System Block Diagram Dual Phase boost PFC LLC resonant DC/DC converter TI Class D 2 x 300 W @ 4 W (UCC28061) (UCC25600) TAS5630 EMI filtering Standby & auxiliary supply +15 V, 200 mA UCC28600 -15 V, 200 mA External use e.g. pre -amp Power Control Unit “DC” Power limit Thermal warning Clip detect from TAS 5630 Figure 1. System Block Diagram The system incorporates 3 power converters: 1.
Overall System Description 4.2 4.2.1 www.ti.com Overcurrent Protection (OCP) Main DC/DC Converter (OCP) There are 2 different current protection modes in the main DC/DC converter. The first mode is primary-side detection and the main purpose of this insures that a fault condition on the 50V rail is not destructive. The current sensing is done by rectifying and filtering the ac-voltage across the resonant capacitor.
Overall System Description www.ti.com 4.4 Standby The UCC28600 supplies the bias power to the PFC and DC/DC converter. When the power consumption on the ±15V rails falls below approx. 1.5W, the UCC28600 turns off the bias power to the main power converters and enters low power/standby mode. During this mode the ±15V is "alive" but the main power rail (50V/25V) is off. When power consumption on the auxiliary voltages goes up again the main power rail is turned on. 4.
Design Considerations www.ti.com 5 Design Considerations 5.1 Dual Interleaved Boost PFC The design of the boost PFC converter follows the design guidelines provided by the documentation of the UCC28061. There are a few exceptions that are explained. First of all, since the load of the power supply in the end, is an audio amplifier, there is a huge difference between what could be called full continuous music power and what is normally understood as full power for a non-dynamic constant load.
Design Considerations www.ti.com 5.2 LLC Resonant DC/DC Converter The design of the resonant converter also general follows the standard procedure shown in the documentation provided together with the UCC25600 but with some alterations based on the demand of the audio application. 5.2.1 LLC Gain The input voltage to the LLC converter is when the boost converter is running approximately 390 VDC. This voltage has a significant ripple at full power.
Design Considerations 5.2.2 www.ti.com Transformer and Resonant Inductor Design For this design, the leakage in the transformer is utilized as the resonant inductor. An external inductor, can be used, but at a higher cost. The leakage inductor in the transformer is created by un-coupled flux between the primary and secondary side. The user does not have to consider saturation of the inductor since it is to be regarded as an air coil.
Design Considerations www.ti.com 5.2.3 Voltage Rail Switching The feedback loop to regulate the rail voltage uses the optocoupler U8 and the shunt regulator U4. When Q10 is OFF the voltage is regulated to approximately 26V. When the Clip-Detect signal goes high, the gate of Q10 is charged and the transistor turns ON effectively paralleling R37 and R38. At the same time Q17 is turned ON signaling, through the optocoupler U9, to turn ON the PFC converter.
Measurements www.ti.com 6 Measurements 6.1 LLC Control Loop Measurement Figure 5. LLC Control Loop The loop gain is measured at 200W. Bandwidth is 2kHz with a phase margin of 90 degrees.
Measurements www.ti.com 6.2 Efficiency at 50V Rail Voltage Efficiency - % 6.2.1 System Efficiency Output Power - W Figure 6. Efficiency at 50V Rail Voltage The measurement is carried out with forced air on the heat sinks. Power range from 50W to 700W. Low Power Efficiency at 25V Rail Voltage Efficiency - % 6.2.2 Output Power - W Figure 7. Efficiency at 25V Rail Voltage Power range is from 0W to 50W 6.2.
Measurements 6.3 www.ti.com EMI Measurements The measurements are only guidelines, and are not made at a certified lab, but shows that the design is capable of passing the EMI limits if implemented properly. 80 80 75 75 70 70 65 65 EN 55022 Voltage on Mains QP 60 55 Level in - dBmV Level in - dBmV EN 55022 Voltage on Mains AV 50 45 40 35 30 45 40 35 30 25 20 20 15 15 10 10 5 5 300 400 500 800 1M 2M 3M 4M 5M 6M 8M 10M Frequency in Hz 0 150k 20M 30M Figure 8.
Schematics www.ti.com 7 Schematics The schematic is done in Orcad Capture, and the Job file is available for down load in the tools folder for the user guide.
Schematics + + + www.ti.com Figure 13.
Schematics + www.ti.com Figure 14.
Schematics + + + www.ti.com Figure 15.
Parts List www.ti.com 8 Parts List Table 2. Bill of Materials Qty Part Reference Description Manufacture First Mfr P/N 2 C1 C13 Ceramic 470pF / 50V / 10% NP0 0603 Capacitor BC Components 0603N471K500NT 2 C2 C8 Ceramic 22µF / 16V / 20% X7R 1210 Capacitor Taiyo Yuden EMK325BJ226MM-T 2 C3 C9 Electrolytic 470µF / 25V / 20% Aluminium 3.
Parts List www.ti.com Table 2. Bill of Materials (continued) Qty Part Reference Description Manufacture First Mfr P/N 1 HEATSINK2 TIC-HSINK-065_1.00 / Heatsink for 2 × TO-220 package, length 50 mm TIC-HSINK-065(1.00) 1 J1 3 pins / 1 row / 5.1mm Pitch Vertical Male Pin header Header On Shore Technology Inc. ED120/3DS 1 J2 4 pins / 1 row / 3.96mm Pitch Vertical Male Pin header Header JST B4P-VH 1 J3 5 pins / 1 row / 2.
Parts List www.ti.com Table 2. Bill of Materials (continued) Qty Part Reference Description Manufacture First Mfr P/N 2 R48 R99 470k / 100mW / 5% / 0603 Resistor Yageo RC0603JR-07470KL 1 R49 5.6k / 100mW / 5% / 0603 Resistor Yageo RC0603JR-075K6L 3 R59 R104 R105 5mR / 1W / 5% / 2010 Resistor Welwyn LRF2010-R005JW 1 R62 215k / 125mW / 1% / 0805 Resistor Yageo RC0805FR-07200KL 6 R63 R64 R68 R69 R73 R74 1.
Parts List 8.2 8.2.1 www.ti.com Heat-Sink Drawings HEATSINK1 The heat sink is based on a ready-made extrusion, type MQ75-1 from Aavid Thermaloy available from Farnell no.: 232970 or KS29.2 from Austerlitz electronic available from ELFA no.: 75-624-81 Figure 16. FET Heat-sink 8.2.2 HEATSINK2 The diode heat sink is based on the same ready-made extrusion, but is 50mm-long, type MQ50-1 from Aavid Thermaloy available from Farnell no.: 232968 or KS29.2-50E from Austerlitz electronic available from ELFA no.
PCB Layout www.ti.com 9 PCB Layout The PCB layout is made on a 1.6mm double sided 70µm Cu FR4 PCB, 110x144mm Gerber files are available as download in the tools folder, or contact the nearest TI representative. Figure 17.
PCB Layout www.ti.com Figure 18.
PCB Layout www.ti.com Figure 19.
References www.ti.com Figure 20. Bottom Layer 10 References 1. 2. 3. 4. 5. UCC28061 Data sheet, (SLUS837) UCC28061EVM 300W Interleaved PFC Pre-Regulator User’s Guide, (SLUU316) PR883: A 300-W, Universal Input, Isolated PFC Power Supply for LCD TV Applications, (SLUU341) UCC25600 Data sheet, (SLUS846) Bing Lu, Wenduo Liu,Yan Liang, Fred C. Lee, and Jacobus D. van Wyk, Optimal Design Methodology for LLC Resonant Converter, IEEE APEC 2006 6.
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【Important Notice for Users of this Product in Japan】 】 This development kit is NOT certified as Confirming to Technical Regulations of Radio Law of Japan If you use this product in Japan, you are required by Radio Law of Japan to follow the instructions below with respect to this product: 1. 2. 3. Use this product 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.
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EVALUATION BOARD/KIT/MODULE (EVM) ADDITIONAL TERMS Texas Instruments (TI) provides the enclosed Evaluation Board/Kit/Module (EVM) under the following conditions: The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user indemnifies TI from all claims arising from the handling or use of the goods.
FCC Interference Statement for Class B EVM devices This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. 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.
【Important Notice for Users of this Product in Japan】 】 This development kit is NOT certified as Confirming to Technical Regulations of Radio Law of Japan If you use this product in Japan, you are required by Radio Law of Japan to follow the instructions below with respect to this product: 1. 2. 3. Use this product 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.
EVALUATION BOARD/KIT/MODULE (EVM) WARNINGS, RESTRICTIONS AND DISCLAIMERS For Feasibility Evaluation Only, in Laboratory/Development Environments. Unless otherwise indicated, this EVM is not a finished electrical equipment and not intended for consumer use.
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