AN1539 STMicroelectronics, AN1539 Datasheet
AN1539
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AN1539 Summary of contents
Page 1
... EN55022 standard. The target efficiency is 70% higher with a maximum duty cycle of 45% at minimum input voltage in discontinuous conduction mode. March 2002 AN1539 - APPLICATION NOTE , to supply 20W output power ac F ...
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... AN1539 - APPLICATION NOTE The regulation is performed on the lowest voltage output, i.e. 2.5V, and cross regulation is achieved by means of a simple circuit and optimized transformer coupling. All the outputs are directly connected to the load, except for the 3.3V. In fact, this output is provided using a standard linear voltage regulator on the 5V output in order to assure high accuracy ...
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... Output 30V Aux Figure 1: Transformer layout ETD29 180 nH 832uH 10% 16uH (typical INPUT DRAIN GROUND 13 PRIMARY SIDE SECONDARY SIDE AN1539 - APPLICATION NOTE Thomson B2 68 turns 2 turns 4 turns 8 turns 7 turns 20 turns 9 turns +30V +22V +12V GROUND +5V +2.5V GROUND 3/15 ...
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... Either kind of diodes, fast recovery PN or Schottky barrier, are used in order to adjust the related output voltage. 1.2 OUTPUT RECTIFIER DIODES SELECTION The selection of the output rectifier diodes has been done considering reverse voltage and forward current rating, as defined in (3) and (4 max I k max AN1539 - APPLICATION NOTE ± ...
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... Figure 3. In fact, this output is usually connected to voltage sensitive circuits such as microprocessors and other low voltage logic devices. is maximum input DC voltage, N DCmax I Ok max ripple LED I LED AN1539 - APPLICATION NOTE is the number of o (5) of 200%, then the limiting resistor trr (6) 5/15 ...
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... Figure 3: Circuit schematic AN1539 - APPLICATION NOTE 6/15 ...
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... – 25V – 25V 6 C 330 nF – 25V 7 C 2200 uF – 25V 8 C 220 uF – 50V 9 C 100 uF – 25V 10 C 2200 uF – 25V 11 C 100 nF – 250V 12 AN1539 - APPLICATION NOTE Value Fuse 5x20 X2 capacitor Note 7/15 ...
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... BYW100-200 11 D 1N4148 12 D 1N4148 13 Q BC556 1 Q BC548A 2 Q BC548A 3 L 330 OREGA VIPer50(022Y SFH617A 2 IC STLD33V 3 IC TL431 4 AN1539 - APPLICATION NOTE X2 capacitor 1A – 600V STMicroelectronics STMicroelectronics STMicroelectronics STMicroelectronics STMicroelectronics STMicroelectronics S+M B82732 STMicroelectronics STMicroelectronics STMicroelectronics 8/15 ...
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... Start up transient is shown in Figure 8 at 110V 220V respectively. Thanks to the internal current generator, that provides constant 2mA current, the ac at 110V DS ac during the first cycles at start up is shown: the voltage never goes DS AN1539 - APPLICATION NOTE and 220V at no-load and full load ac ac and 9/15 ...
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... Figure load at 110V DS amb out1 out2 out3 (V) (V) (V) 2.53 3.28 5.41 2.53 3.28 5.41 2.53 3.28 5.40 2.53 3.28 5.40 =30×C. amb out1 out2 out3 (V) (V) (V) 2.49 3.24 5.18 2.49 3.24 5.19 2.50 3.24 5.18 2.49 3.24 5.19 and 220V ac ac AN1539 - APPLICATION NOTE capacitor. DD =30º out4 out5 out6 (V) (V) (V) 12.91 24.6 32.5 12.92 24.7 32.5 12.90 24.6 32.5 12.89 24.6 32 out4 out5 out6 (V) (V) (V) 12.05 22.2 32.9 12.05 22.2 32.8 12.05 22.1 32.8 12.05 22.1 32.9 10/15 ...
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... Figure full load at 110V DS Figure 7: V during start-up at 110V DS and 220V ac ac and 220V ac ac AN1539 - APPLICATION NOTE 11/15 ...
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... Figure 8: Start-up time at 110V Figure 9: Output voltage ripple at V and 220V ac ac =220V : 1) 2.5V, 2) 5V, 3) 12V, 4) 22V in ac AN1539 - APPLICATION NOTE 12/15 ...
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... Figure 11: Short circuit at Pout DD =220V . In both cases the power dissipation is limited since the in ac and V =220V . 22V output (V =110V max 22V output (V =110V max in ac AN1539 - APPLICATION NOTE voltages are shown as the 22V output is and V =220V ) in ac and V =265V ) in ac 13/15 ...
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... AV (average) limit, passing the pre-compliance test. Figure 12: Conducted emissions at 110V REF 150 kHz Figure 13: Conducted emissions at 220V REF 150kHz and 230V input voltage, respectively. Although peak detector has ac ac (limits EN55022B) ac (limits EN55022B) ac AN1539 - APPLICATION NOTE 30 MHz 30 MHz 14/15 ...
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... Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. amb T at 110V The ST logo is a trademark of STMicroelectronics STMicroelectronics GROUP OF COMPANIES http://www.st.com AN1539 - APPLICATION NOTE =23ºC. Only one heatsink has been T at 220V ac 64 103 15/15 ...