UM10781 - NXP Semiconductors
Contents
1. 5 Connecting the TEA1892DB1226 add on board 7 11 Introduction 0 0 0 cece eee eee 11 Test equipment and conditions 11 EMClONGCY uisus ele earn Ebert eae Hie 11 Operational behavior 13 Conducted EMI 15 Schematic and Bill Of Materials BOM 17 PCB layout 1 icm 19 lt 20 21 Definitions lssscoc e Rm 21 DiSclaltfiers raped ae dox tud 21 Trademarks 21 Contenls eso sre e ee ees 22 Please be aware that important notices concerning this document and the product s described herein have been included in section Legal information B V 2014 All rights reserved For more information please visit http Awww nxp com For sales office addresses please send an email to salesaddresses nxp com Date of release 20 May 2014 Document identifier UM107812. UM10781 PE GreenChip TEA1892DB1226 synchronous rectifier controller add on board Rev 1 20 May 2014 User manual Document information Info Content Keywords TEA1892DB1226 Synchronous Rectifier SR driver high efficiency TSOP6 flyback converter Abstract This user manual describes how the TEA1892DB1226 add on board can be used in a flyback converter The add on board contains a TEA1892TS SR controller in TSOP 6 package The add on board also contains a power MOSFET as well as a charge pump circuit to generate the supply voltage for the SR controller The add on board replaces the rectifier diode at the secondary side of the flyback converter It is intended for high side applications but with minor modifications it can also be used for low side applications NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board Revision history Rev Date Description v 1 20140520 first issue Contact information For more information please visit http www nxp com For sales office addresses please send an email to salesaddresses nxp com UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 2 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board 1 Introduction This document describes the TEA1892DB1
3. UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 3 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board 3 TEA1892TS SR controller UM10781 The TEA1892TS is a member of the new generation of Synchronous Rectifier SR controller ICs for switched mode power supplies Its high level of integration allows the design of a cost effective power supply with a very low number of external components The IC provides synchronous rectification on the secondary side for discontinuous conduction mode and quasi resonant mode flyback converters It is a successor to the TEA1792TS synchronous rectifier controller IC The TEA1892TS provides improved performance at lower loads by disabling cycle shipping An efficient control algorithm built into the IC determines when a MOSFET is switched on or off After a negative voltage lower than 220 mV typical is sensed on the SRSENSE pin the driver output voltage is driven HIGH Then the external MOSFET is switched on When Vsrsense rises to Vregiarv 42 mV 30 mV the driver output voltage is regulated to maintain the Vreg arv on the SRSENSE pin When the SRSENSE voltage is above the Vdeact drv level 12 mV typical the driver output is pulled to ground After switch on of the SR MOSFET the input signal on the SRSENSE pin is blan
4. All the other SMD components are mounted on the back side ACY12VO e LS 4V SEC GND e112804 000 He 013249 2 PSMN3R3 100PS see Table 5 021 R3 c5 y psy inn iat ora mr 5 I wat pw UN f n 1 UN 9 013250 U1 TEA1892TS see Table 5 b Bottom view Fig5 TEA1892DB1226 add on board photographs UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 6 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board 30 TEA18 B12265 REU xx 12 0 EN 94V 0 GND t112804 7 30 mm aaa 013251 Fig6 TEA1892DB1226 add on board dimensions 4 2 Connecting the TEA1892DB1226 add on board The TEA1892DB1226 add on board replaces the existing rectifier diode at the secondary side of the flyback supply in high side and low side applications In Figure 7 the internal and external supply options for high side applications are shown Figure 8 shows the possibilities for low side applications UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 7 of 22 N
5. 000139 Fig4 Application diagram for low side rectification In high side rectification Figure 3 the supply voltage for the TEA1892TS is normally derived from an auxiliary winding on the transformer secondary side In low side rectification Figure 4 the output voltage Vour is used in most cases as the TEA1892TS supply High side rectification is the preferred application for the best EMI performance Add on board set up The TEA1892DB1226 add on board is designed for incorporation into existing flyback power supplies by replacing the secondary rectifier diode Although the add on board was designed for high side rectifier applications it is also possible to replace the rectifier diode in low side applications The add on board consists of The TEA1892TS in TSOP 6 package AMOSFET with a typical Rpson of 3 3 mO Acharge pump circuit capable of delivering the SR controller supply voltage All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 5 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board Figure 5 shows the top and bottom views of the add on board Only the MOSFET is soldered to the front side of the add on board The MOSFET DRAIN middle pin is soldered to the large copper plane The plane is connected via 15 interconnects to the back side of the add on board
6. 226 add on board A functional description and a set of measurements illustrate the performance of the TEA1892DB1226 add on board The add on board also contains a charge pump circuit capable of delivering the supply voltage for the SR controller The charge pump circuit eliminates the auxiliary transformer winding in the flyback converter A flyback converter board in which the secondary part diode can be replaced by the add on board is required to use the add on board correctly 2 Safety Warning WARNING Lethal voltage and fire ignition hazard The non insulated high voltages that are present when operating this product constitute a risk of electric shock personal injury death and or ignition of fire This product is intended for evaluation purposes only It shall be operated in a designated test area by personnel qualified according to local requirements and labor laws to work with non insulated mains voltages and high voltage circuits This product shall never be operated unattended The board application is AC mains voltage powered Avoid touching the board when power is applied An isolated housing is obligatory when used in uncontrolled non laboratory environments Always provide galvanic isolation of the mains phase using a variable transformer The following symbols identify isolated and non isolated devices 019aab173 019aab174 a Isolated b Non isolated Fig 1 Isolated and non isolated symbols
7. 96 25 25 43 19 288 1 1634 88 24 50 51 56 19 265 2 3091 86 27 75 76 01 19 242 3 4709 87 87 100 100 63 19 218 4 6281 88 35 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 12 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board aaa 012392 92 efficiency 90 88 86 load percentage TEA1892TS SR at 115 V 60 Hz TEA1892TS SR at 230 V 50 Hz STPS20M100S Schottky diode at 115 V 60 Hz STPS20M100S Schottky diode at 230 V 50 Hz Fig 10 Efficiency as a function of percentage load 5 3 Operational behavior Figure 11 a and Figure 11 b show oscilloscope traces with the typical waveforms The waveforms were measured when the TEA1892DB1226 SR demo board was connected to the 90 W TEA1752 adapter board as a high side application The two waveforms represent the gate drive voltage purple TEA1892TS SR controller DRIVER pin and the secondary output current green The output current was measured using a voltage probe directly connected over a 100 mQ resistor in series with the secondary side ground track Figure 11 a shows the waveforms for a 4 A load with the SELREG pin open This configuration sets the regulation level at 30 mV Figure 11 b shows the waveforms for a 4 A load with the SELREG pin connected to g
8. synchronous rectifier controller add on board 5 Measurements UM10781 5 1 Introduction The performance has been measured on mainboard TEA1752 90 W flyback and PFC see Ref 3 with the add on module TEA1892DB1226 connected for the high side SR 5 1 1 Test equipment and conditions The following test equipment is used AC source Agilent 6812B Power meter Yokogawa WT210 with harmonics option DC electronic load Chroma Model 63103 Digital oscilloscope Yokogawa DL1640L Current probe Yokogawa 701933 30 A 50 MHz 100 MHz high voltage differential probe Yokogawa 700924 500 MHz low voltage differential probe Yokogawa 701920 Multimeter Keithley 2000 ElectroMagnetic Compatibility EMC receiver Rohde amp Schwarz ESPI 3 Line Impedance Standardization Network LISN ENV216 The board was tested under the following conditions Adapter on the lab table with heat sinks facing downwards The adapter has no casing Ambient temperature between 20 C and 25 C Measurements were made after stabilization of temperature according to test method for calculating the efficiency of single voltage external AC to DC and AC to AC power supplies of ENERGY STAR 5 2 Efficiency Test conditions The adapter is set to maximum load and preheated until temperature stabilization is achieved Temperature stabilization is established for every load step before recording any measurements Remark The output voltage is measured at the ou
9. XP Semiconductors UM10781 UM10781 TEA1892DB1226 synchronous rectifier controller add on board a 1 b Fig 7 TEA1892DB1226 SRSENSE DRIVER SEC GND SOURCE DRAIN connect D1 connect connect remove D1 4 secondary side flyback I aaa 012366 Internal charge pump supply TEA1892DB1226 CHARGE PUMP SOURCE connect connect DRIVER OUT PSMN3R3 100PS see Table 5 External auxiliary supply TEA1892DB1226 add on board high side connections M 1 remove D1 e secondary side flyback 012389 Figure 7 shows the connections to be made when the internal charge pump supply is used This charge pump generates a Vcc supply with a value of Vout 2 V The TEA1892TS supply must be between 8 5 V and 38 V see Ref 1 The Vout voltage must be between 10 5 V to 40 V A flyback adapter output voltage is normally within this range All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 8 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board When there is an auxiliary voltage available in the flyback adapter application it can be used to supply the TEA1892TS Vcc See Figure 7 b In both situations the MOSFET SOURCE and DRAIN leads are
10. a designated test area by personnel that is qualified according to local requirements and labor laws to work with non insulated mains voltages and high voltage circuits The product does not comply with IEC 60950 based national or regional safety standards NXP Semiconductors does not accept any liability for damages incurred due to inappropriate use of this product or related to non insulated high voltages Any use of this product is at customer s own risk and liability The customer shall fully indemnify and hold harmless NXP Semiconductors from any liability damages and claims resulting from the use of the product Translations A non English translated version of a document is for reference only The English version shall prevail in case of any discrepancy between the translated and English versions 9 3 Trademarks Notice All referenced brands product names service names and trademarks are the property of their respective owners GreenChip is a trademark of NXP Semiconductors N V NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 21 of 22 NXP Semiconductors UM10781 TEA1892DB1226 synchronous rectifier controller add on board 10 Contents A amp oN 5 1 1 Introduction 3 Safety 3 TEA1892TS SR controller 4 General application of the TEA1892TS 5 Add on board lt
11. emiconductors its affiliates or their suppliers be liable to customer for any special indirect consequential punitive or incidental damages including without limitation damages for loss of business business interruption loss of use loss of data or information and the like arising out the use of or inability to use the product whether or not based on tort including negligence strict liability breach of contract breach of warranty or any other theory even if advised of the possibility of such damages Notwithstanding any damages that customer might incur for any reason whatsoever including without limitation all damages referenced above and all direct or general damages the entire liability of NXP Semiconductors its affiliates and their suppliers and customer s exclusive remedy for all of the foregoing shall be limited to actual damages incurred by customer based on reasonable reliance up to the greater of the amount actually paid by customer for the product or five dollars US 5 00 The foregoing limitations exclusions and disclaimers shall apply to the maximum extent permitted by applicable law even if any remedy fails of its essential purpose Safety of high voltage evaluation products The non insulated high voltages that are present when operating this product constitute a risk of electric shock personal injury death and or ignition of fire This product is intended for evaluation purposes only It shall be operated in
12. inserted and soldered at the removed diode D1 anode and cathode connections TEA1892DB1226 SRSENSE DRIVER CHARGE PUMP SEC GND remove D1 connect connect connect D1 I secondary side flyback aaa 012390 a Internal charge pump supply TEA1892DB1226 DRIVER SEC GND Vour remove D1 connect connect D1 I secondary side flyback aaa 012391 1 PSMN3R3 100PS see Table 5 b Vour supply Fig 8 TEA1892DB1226 add on board low side connections UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 9 of 22 UM10781 TEA1892DB1226 synchronous rectifier controller add on board NXP Semiconductors In low side applications the board is easily connected Using either the internal charge pump supply or with Vour as the supply The required connections are shown in Figure 8 Figure 9 shows an example of the TEA1892DB1226 add on board used in a typical 90 W flyback adapter aaa 002587 Fig 9 Example of TEA1892DB1226 add on board connected to the APBADC031 TEA1752 90 W flyback adapter All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved Rev 1 20 May 2014 10 of 22 UM10781 User manual NXP Semiconductors U M1 0781 TEA1892DB1226
13. ked during the tact sr min 1 5 us typical This action eliminates false switch off due to high frequency ringing at the start of the secondary stroke When the secondary current is reduced until the SRSENSE voltage is V er the internal control loop maintains the Vreg arv level across the MOSFET Maintaining Vreg arv in this instance is achieved when the Vpniygn voltage is decreased This reduction enables the external power switch to be switched off quickly when the current through the switch reaches zero The zero current is detected by sensing a Vdeactiarv 712 mV typical level on the SRSENSE pin SRSENSE GND Vcc aaa 001385 Fig 2 Pin configuration TEA1892TS TSOP6 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 4 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board 4 General application of the TEA1892TS UM10781 4 1 General application diagrams of high side and low side rectification are given in Figure 3 and Figure 4 See Figure 2 for the relevant pin numbers Vo RSRSENSE Cout PRIMARY SIDE CONTROLLER SRSENSE aaa 000138 Fig 3 TR Vo RSRSENSE spsENSE Qprim QsecT PRIMARY Cee i SIDE RDRIVER DRIVER CONTROLLER
14. of use of such information 9 2 Disclaimers Limited warranty and liability Information in this document is believed to be accurate and reliable However NXP Semiconductors does not give any representations or warranties expressed or implied as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information NXP Semiconductors takes no responsibility for the content in this document if provided by an information source outside of NXP Semiconductors In no event shall NXP Semiconductors be liable for any indirect incidental punitive special or consequential damages including without limitation lost profits lost savings business interruption costs related to the removal or replacement of any products or rework charges whether or not such damages are based on tort including negligence warranty breach of contract or any other legal theory Notwithstanding any damages that customer might incur for any reason whatsoever NXP Semiconductors aggregate and cumulative liability towards customer for the products described herein shall be limited in accordance with the Terms and conditions of commercial sale of NXP Semiconductors Right to make changes NXP Semiconductors reserves the right to make changes to information published in this document including without limitation specifications and product descriptions at any time and without notice This document supe
15. ous rectifier controller add on board 7T PCB layout Figure 15 shows the layout of the PCB TEA1892DB1226 REU xx ACYi2vo 94V 0 TE TP aaa 013252 a Top view aaa 013253 b Bottom view Fig 15 TEA1892DB1226 PCB layout UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 19 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board 8 References 1 TEA1892TS Data sheet GreenChip synchronous rectifier controller 2 AN11149 Application note GreenChip TEA1792 synchronous rectifier controller 3 UM10403 User Manual 90 W notebook adapter with TEA1752T and TEA1791T UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 20 of 22 NXP Semiconductors UM10781 TEA1892DB1226 synchronous rectifier controller add on board 9 Legal information 9 1 Definitions Draft The document is a draft version only The content is still under internal review and subject to formal approval which may result in modifications or additions NXP Semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences
16. rive resistor R2 value 0 Q Pass criteria CISPR22 Class B m am r n FERES Pod HE guka lt a 18 cae 002815 Remark The conducted EMI measurement result for 115 V neutral is comparable to the 115 V line Fig 12 Conducted EMI at 115 V AC line UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 15 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board aaa 002816 Remark The conducted EMI measurement result for 230 V neutral is comparable to the 230 V line Fig 13 Conducted EMI at 230 V AC line UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 16 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board 6 Schematic and Bill Of Materials BOM The components used are shown in Figure 14 Table 5 describes the components required for the add on board application SEC GND GND SRSENSE DRIVER FRONT GROUND PLANE SOURCE DRAIN GATE aaa 012395 Fig 14 Schematic diagram SR add on board TEA1892DB1226 UM10781 All information provided in this document is s
17. round This configuration sets the regulation level to 42 mV UM10781 All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 13 of 22 NXP Semiconductors U M1 0781 UM10781 TEA1892DB1226 synchronous rectifier controller add on board YOKOGAWA 2012 02 20 14 28 51 Norm Hi Res Stopped H H IntP 2 5GS s Suv GS AR 2 DC Full OC Full Fx 500V dw 5 00 A div 21 30 V 10 1 00A 1V aaa 002794 a 4Aload SELREG pin open regulation level 30 mV YOKOGAWA 2012 02 20 14 26 17 Norm HiRes Stopped 19 Intp 2 5GS s Sus div 4 FL IP d em Pda DC Full DC Full a t 5 00 V div 5 00 A diy 21 30 V 10 1 100A 1V DCOF aaa 002814 1 Purple gate drive current 2 Green secondary output current b 4A load SELREG pin connected to ground regulation level 42 mV Fig 11 TEA1892DB1226 SR and 90 W TEA1752 as a high side application All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 14 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchronous rectifier controller add on board 5 4 Conducted EMI Tests Test conditions The adapter is subjected to maximum load The ground connection of the output cable is connected to EMC ground e The gate d
18. rsedes and replaces all information supplied prior to the publication hereof Suitability for use NXP Semiconductors products are not designed authorized or warranted to be suitable for use in life support life critical or safety critical systems or equipment nor in applications where failure or malfunction of an NXP Semiconductors product can reasonably be expected to result in personal injury death or severe property or environmental damage NXP Semiconductors and its suppliers accept no liability for inclusion and or use of NXP Semiconductors products in such equipment or applications and therefore such inclusion and or use is at the customer s own risk Applications Applications that are described herein for any of these products are for illustrative purposes only NXP Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification Customers are responsible for the design and operation of their applications and products using NXP Semiconductors products and NXP Semiconductors accepts no liability for any assistance with applications or customer product design It is customer s sole responsibility to determine whether the NXP Semiconductors product is suitable and fit for the customer s applications and products planned as well as for the planned application and use of customer s third party customer s Customers should provide appropriate de
19. sign and operating safeguards to minimize the risks associated with their applications and products UM10781 All information provided in this document is subject to legal disclaimers NXP Semiconductors does not accept any liability related to any default damage costs or problem which is based on any weakness or default in the customer s applications or products or the application or use by customer s third party customer s Customer is responsible for doing all necessary testing for the customer s applications and products using NXP Semiconductors products in order to avoid a default of the applications and the products or of the application or use by customer s third party customer s NXP does not accept any liability in this respect Export control This document as well as the item s described herein may be subject to export control regulations Export might require a prior authorization from competent authorities Evaluation products This product is provided on an as is and with all faults basis for evaluation purposes only NXP Semiconductors its affiliates and their suppliers expressly disclaim all warranties whether express implied or statutory including but not limited to the implied warranties of non infringement merchantability and fitness for a particular purpose The entire risk as to the quality or arising out of the use or performance of this product remains with customer In no event shall NXP S
20. tput of the board The arithmetic average of the four efficiency measurements must be 2 87 for adapters to comply with ENERGY STAR EPS2 0 Universal mains adapters must pass the criteria at both 115 V 60 Hz and 230 V 50 Hz To meet this criteria the PFC must be off at 25 load and preferably on at 50 load The performance was measured with and without SR so diode ISO MOSFET All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 11 of 22 NXP Semiconductors UM10781 UM10781 TEA1892DB1226 synchronous rectifier controller add on board Table 1 Efficiency using TEA1892TS with MOSFET PSMN3RG3 at 115 V 60 Hz Load Pin W Vour V lo A n 26 25 24 79 19 398 1 165 91 16 50 49 05 19 384 2 31 91 29 75 73 48 19 371 3 477 91 66 100 98 13 19 357 4 622 91 17 Table 2 Efficiency using TEA1892TS with MOSFET PSMN3RG3 at 230 V 50 Hz Load Pin W Vour V lo A n 96 25 24 90 19 399 1 165 90 76 50 50 44 19 385 2 31 88 78 75 74 14 19 372 3 477 90 85 100 97 74 19 360 4 622 91 55 Table 3 Efficiency using STPS20M100S Schottky diode at 115 V 60 Hz Load Pin W Vout V lo A n 26 25 25 29 19 288 1 1634 88 73 50 50 24 19 257 2 3091 88 50 75 75 52 19 242 3 4709 88 44 100 101 33 19 218 4 6262 87 74 Table4 Efficiency using STPS20M100S Schottky diode at 230 V 50 Hz Load Pin W Vour V lo A n
21. ubject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 17 of 22 NXP Semiconductors UM10781 UM10781 TEA1892DB1226 synchronous rectifier controller add on board Table 5 Bill of materials Reference Component Package Remark R1 100 kQ 0805 R2 4 7 Q 0805 R3 1 ko 0805 R4 not mounted 0805 S R5 not mounted 0805 R6 not mounted 0805 C1 47 nF 50V 0805 C2 1 uF 50V 0805 C3 200 pF 200 V 0805 C4 not mounted 0805 5 not mounted 0805 D1 BAS321 SOD523 D3 BAV99 SOT23 DZ1 BZX84J C15 SOD323F DZ2 not mounted SOD323F M1 2N7002 SOT23 M2 MOSFET PSMN3R3 100P TO220AB Rpson 3 3 MQ U1 TEA1892TS TSOP6 Components C2 R2 R3 R6 C5 and M2 are needed for the TEA1892TS standard application Components R1 C1 DZ1 D1 and M1 combine to the charge pump circuit The charge pump circuit that generates the supply voltage for the TEA1892TS Mount optional components R4 R5 C4 and DZ2 when false MOSFET switch off occurs False MOSFET switch off occurs when large ringing is present on the transformer secondary side e a MOSFET with a very low Rpgon is used See Ref 2 for more detailed information All information provided in this document is subject to legal disclaimers NXP B V 2014 All rights reserved User manual Rev 1 20 May 2014 18 of 22 NXP Semiconductors U M1 0781 TEA1892DB1226 synchron
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