EVL6566A-75WES4 STMicroelectronics, EVL6566A-75WES4 Datasheet

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... Introduction This application note describes the characteristics and the features reference board (p/n EVL6566A-75WES4), tailored on specifications of a typical high-end portable computer power supply. The peculiarities of this design are the very high efficiency at light load and the excellent global efficiency for a two-stage architecture. The high efficiency at high load is achieved by not using synchronized rectification at the secondary side and therefore offering a very cost-effective solution ...

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Contents Contents 1 Main characteristics and circuit description . . . . . . . . . . . . . . . . . . . . . 5 2 Efficiency measurement . . . . . . . ...

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AN2941 List of tables Table 1. Overall efficiency compared to “EPA rev. 2.0 EPS” ...

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... Electrical diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 6. Light-load efficiency measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 7. EVL6566A-75WES4 compliance to EN61000-3-2 standard at 230 Vac-50 Hz, full load . . 15 Figure 8. EVL6566A-75WES4 compliance to JEITA-MITI standardat 100 Vac-50 Hz, full load . . . . 15 Figure 9. Flyback stage waveforms at 115 V- full load Figure 10. Flyback stage waveforms at 230 V - full load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 11. Flyback stage waveforms at 115 V- load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 12 ...

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AN2941 1 Main characteristics and circuit description The main features of the SMPS are listed as follows: Universal input mains range: 90÷264 Vac - frequency 45 ÷ ● ● Output voltage continuous operation ...

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Main characteristics and circuit description Figure 2. Typical transition mode PFC electrical diagram To overcome this problem, in this board a “sensorless” PFC solution has been implemented ( Figure 3 ). The information relevant to input and output voltages is ...

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AN2941 Operation of the “sensorless PFC” is explained as follows, referring to a) During the MOSFET OFF-time the voltage applied across the boost inductance is the difference between the output and the input voltage and C 2 where ...

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Main characteristics and circuit description During light-load operation the PFC controller is stopped by the PWM controller, so the MOSFET doesn’t switch and there is no reflected voltage on the auxiliary winding. C and C are no longer charged and ...

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AN2941 The output rectifiers are two dual center tap Schottky diodes (D7 and D5) in parallel. They have been selected according to the maximum reverse voltage, forward voltage drop and power dissipation. The snubber made up of R14, R66 and ...

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Main characteristics and circuit description Output voltage feedback loop The output regulation is done by means of two control loops, a voltage and a current loop working alternatively. A dedicated control IC, the TSM1014 (U5), has been used. It integrates ...

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AN2941 Overtemperature protection Thermistor R58, connected to L6566A DIS pin (#8), provides for a thermal protection of the flyback MOSFET (Q5). The L6563S PWM_LATCH pin (activated in case of PFC loop failures or PFC inductor saturation) is connected to L6566A ...

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Main characteristics and circuit description Figure 5. Electrical diagram 12/37 Doc ID 15447 Rev 3 AN2941 ...

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AN2941 2 Efficiency measurement EPA rev. 2.0 external power supply compliance Table 1 shows the no-load consumption and the overall efficiency, measured at the nominal mains voltages. As shown, these values are fully compliant with the EPA rev 2.0 external ...

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Efficiency measurement requirements. The major computer manufacturers require efficiency higher than 70% from input power and efficiency higher than 75% from input power. Figure 6 shows the demonstration board’s measured ...

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... Figure 8.   1 0.1 0.0 1 0.00 1 0.000 1 1 THD = 4.52 0.991 Doc ID 15447 Rev 3 Harmonic content measurement EVL6566A-75WES4 compliance to JEITA-MITI standard at 100 Vac-50 Hz, full load Me asure d va lue JEIDA-MITI Cla s s-D limits Harm onic [n] 15/37 ...

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Functional check 4 Functional check The following figures show some flyback waveforms during steady-state operation and the L6563S TBO function is depicted, setting different PFC output voltages according to the mains input voltage. At nominal load conditions, in edge triggers ...

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AN2941 Standby and no-load operation In Figure 13 and works in burst mode. When the feedback voltage at pin COMP falls below 2.65 V (typical), the IC is disabled and its consumption is reduced. The chip is re-enabled as the ...

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Functional check Figure 15. Transition full load to no load at 265 Vac-50 Hz CH1: Drain voltage CH3: Output voltage CH2: Vcc CH4: Output current Overcurrent and short-circuit protection In this demonstration board the overcurrent is managed by TSM1014 (U5), ...

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... Furthermore from the graph we can note that, during the SS voltage ramp-up, the transferred power is limited. Overvoltage and open loop protection The EVL6566A-75WES4 board implements two different open loop protections, one for each stage. The PFC controller L6563S is equipped with an OVP monitoring the output voltage by the PFC_OK (#7) pin with a resistor divider (R3, R5, R11 high, R10 and R19 low) ...

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Functional check Figure 19. EVL6566-75WES4 PFC open loop at 115 Vac- full load CH1: Drain voltage CH2: PFC output voltage To restart the system the input power must be recycled. The PFC_OK pin has two functions as a ...

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AN2941 HV startup circuit turns on and begins to operate periodically in order to keep VCC between VCCON and VCCON-0 Figure 20. Flyback open loop at 230 V-50 Hz half load CH1: VFF voltage CH3: ZCD voltage CH2: ...

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Functional check In the following table the output voltage at OVP intervention are given. The measures therefore demonstrate that, as previously explained, the L6566A sensing technique provides a very stable OVP intervention threshold over the entire mains voltage and load ...

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AN2941 5 Thermal map In order to check the design reliability, a thermal mapping by means camera was done. Figure 23 and nominal input voltage. Some pointers visible on the pictures have been placed across key components ...

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Conducted emission pre-compliance test 6 Conducted emission pre-compliance test Figure 25 and 26 nominal mains voltages. The limits shown in the diagrams are from EN55022 Class-B, which is the most popular regulation for domestic equipment and it has more stringent ...

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Bill of material Table 6. Bill of material Des. Part type / part value C1 2n2F C2 2n2F C3 330nF C5 470nF - 400V C6 100µF - 450V C7 2n2F C8 1nF C9 100nF C10 1nF C11 1nF C12 ...

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... AVX 1206 Rubycon DWG AVX 1206 AVX 0805 AVX 0805 AVX 1206 AVX 0805 AVX 1206 AVX 1206 AVX 1206 AVX 1206 AVX 0805 AVX PTH Vishay DO-41 Vishay GBU STYLE STMicroelectronics DO-41 STMicroelectronics DO - 201 STMicroelectronics TO - 220FP Vishay SMA STMicroelectronics TO - 220FP ...

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... Phoenix contact Phoenix contact Input EMI filter PFC inductor 1u5F - radial inductor N-channel power MOSFET STMicroelectronics NPN small signal BJT N-channel power MOSFET STMicroelectronics NPN small signal BJT NPN small signal BJT NTC resistor - S237 Supplier Case style / package SMA Vishay MINIMELF ...

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Table 6. Bill of material (continued) Des. Part type / part value R8 47K SMD standard film res - 1/ 100ppm/°C R10 27K SFR25 axial stand. film res - 0. 100ppm/°C R11 2M2 SFR25 ...

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Table 6. Bill of material (continued) Des. Part type / part value R39 56K SMD standard film res - 1/ 100ppm/°C R42 16K SMD standard film res - 1/ 100ppm/°C R45 2K2 SMD standard ...

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... SMD standard film res - 1/ 250ppm/°C T1 SRW32EC-T01H114 U1 L6563S U3 SFH617A-4 U5 TSM1014AIST U6 L6566A Description Power transformer Transition-mode PFC controller Optocoupler Low consumption CC/CV controller Multi-mode PWM controller Supplier Case style / package Vishay 0805 Vishay 1206 Vishay 1206 TDK DWG STMicroelectronics SO-14 Infineon DIP4-10.16mm STMicroelectronics Mini SO-8 STMicroelectronics SO-16N ...

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AN2941 8 PFC coil specifications General description and characteristics ● Application type: consumer, home appliances ● Transformer type: open ● Coil former: vertical type, 5+3 pins ● Max. temp. rise: 45 °C ● Max. operating ambient temperature: 60 °C ● ...

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PFC coil specifications Mechanical aspect and pin numbering ● Maximum height from PCB ● Coil former type: vertical, 5+3 pins ● Pins # are removed ● External copper shield: not insulated, wound around the ferrite ...

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AN2941 9 Transformer specifications General description and characteristics ● Application type: consumer, home appliances ● Transformer type: open ● Coil former: horizontal type, 9+9 pins ● Max. temp. rise: 45 °C ● Max. operating ambient temperature: 60 °C ● Mains ...

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Transformer specifications Table 8. Transformer winding data Pins Winding 5-6 3-1 Primary - A 8-10 4-2 Primary - B 1. All terminal wires have to be insulated with tubes 2. Primaries A and B are in parallel Figure 30. Transformer ...

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AN2941 Mechanical aspect and pin numbering ● Maximum height from PCB ● Coil former type: horizontal, 9+9 pins (pin 2 removed) ● Pin distance ● Row distance ● External copper shield: not insulated, wound ...

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Revision history 10 Revision history Table 9. Document revision history Date 19-May-2009 25-May-2009 18-Sep-2009 36/37 Revision 1 Initial release 2 Updated Figure 2 and 3 Updated Figure 8 and Doc ID 15447 Rev 3 Changes Figure 3 Table 6 AN2941 ...

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... AN2941 Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...