Application Note, V1.0, 12 March 2012 A pp l i c at i on N ot e AN- EVAL-ICE2QR1065Z 24W 12V E valuation Board with Quasi Resonant CoolSET® ICE2QR1065Z Power Management & Supply N e v e r s t o p t h i n k i n g . Published by Infineon Technologies AG 81726 Munich, Germany © 2012 Infineon Technologies AG All Rights Reserved. Legal Disclaimer The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics. With respect to any examples or hints given herein, any typical values stated herein and/or any information regarding the application of the device, Infineon Technologies hereby disclaims any and all warranties and liabilities of any kind, including without limitation, warranties of non-infringement of intellectual property rights of any third party. Information For further information on technology, delivery terms and conditions and prices, please contact the nearest Infineon Technologies Office (www.infineon.com). Warnings Due to technical requirements, components may contain dangerous substances. For information on the types in question, please contact the nearest Infineon Technologies Office. Infineon Technologies components may be used in life-support devices or systems only with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body or to support and/or maintain and sustain and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may be endangered. EVAL-ICE2QR1065Z-24W 24W 12V Demoboard using ICE2QR1065Z on board Revision History: 12 March 2012 Previous Version: Page V1.0 none Subjects (major changes since last revision) ® 24W12V Evaluation Board with Quasi-Resonant CooLSET ICE2QR1065Z License to Infineon Technologies Asia Pacific Pte Ltd AN-PS0063 Winson Wong [email protected] Eric Kok [email protected] We Listen to Your Comments Any information within this document that you feel is wrong, unclear or missing at all? Your feedback will help us to continuously improve the quality of this document. Please send your proposal (including a reference to this document) to: [email protected] Application Note 4 12 March 2012 EVAL-ICE2QR1065Z-24W Table of Contents 1 Content ............................................................................................................... 6 2 Evaluation Board ............................................................................................... 6 3 List of Features .................................................................................................. 6 4 Technical Specifications ................................................................................... 7 5 Circuit Description............................................................................................. 7 5.1 Mains Input and Rectification..................................................................................................7 5.2 Integrated MOSFET and PWM Control ....................................................................................7 5.3 Snubber Network .....................................................................................................................7 5.4 Output Stage ............................................................................................................................7 5.5 Feedback Loop.........................................................................................................................7 6 Circuit Operation ............................................................................................... 8 6.1 Startup Operation.....................................................................................................................8 6.2 Normal Mode Operation...........................................................................................................8 6.3 Primary side peak current control...........................................................................................8 6.4 Digital Frequency Reduction ...................................................................................................8 6.5 Burst Mode Operation..............................................................................................................8 7 Protection Features ........................................................................................... 9 7.1 Vcc under voltage and over voltage protection......................................................................9 7.2 Foldback point protection .......................................................................................................9 7.3 Open loop/over load protection...............................................................................................9 7.4 Adjustable output overvoltage protection ..............................................................................9 7.5 Short winding protection .........................................................................................................9 7.6 Auto restart for over temperature protection..........................................................................9 8 Circuit diagram ................................................................................................ 10 8.1 PCB Topover layer .................................................................................................................11 8.2 PCB Bottom Layer .................................................................................................................12 9 Component List ............................................................................................... 13 10 Transformer Construction .............................................................................. 15 11 Test Results ..................................................................................................... 16 11.1 Efficiency and standby performance ....................................................................................16 11.2 EMI Performance....................................................................................................................17 12 Waveforms and scope plots ........................................................................... 19 12.1 Startup at 85Vac and 24W load..............................................................................................19 12.2 Soft-Start with 24W Load .......................................................................................................20 12.3 Load Transient Response......................................................................................................20 12.4 Burst Mode Operation............................................................................................................21 12.5 Protection modes...................................................................................................................22 13 References ....................................................................................................... 23 Application Note 5 12 March 2012 EVAL-ICE2QR1065Z-24W 1 Content This application note is a description of 24W switching mode power supply evaluation board designed in a ® quasi resonant flyback converter topology using ICE2QR1065Z Quasi-resonant CoolSET .The target application of ICE2QR1065Z are for set-top box, portable game controller, DVD player, netbook adapter and ® auxiliary power supply for LCD TV, etc. With the CoolMOS integrated in this IC, it greatly simplifies the design and layout of the PCB. Due to valley switching, the turn on voltage is reduced and this offers higher conversion efficiency comparing to hard-switching flyback converter. With the DCM mode control, the reverse recovery problem of secondary rectify diode is relieved. And for its natural frequency jittering with line voltage, the EMI performance is better. Infineon’s digital frequency reduction technology enables a quasi-resonant operation till very low load. As a result, the system efficiency, over the entire load range, is significantly improved compared to conventional free running quasi resonant converter implemented with only maximum switching frequency limitation at light load. In addition, numerous adjustable protection functions have been implemented in ICE2QR1065Z to protect the system and customize the IC for the chosen application. In case of failure modes, like open control-loop/over load, output overvoltage, and transformer short winding, the device switches into Auto Restart Mode or Latch-off Mode. By means of the cycle-by-cycle peak current limitation plus foldback point correction, the dimension of the transformer and current rating of the secondary diode can both be optimized.Thus, a cost effective solution can be easily achieved. 2 Evaluation Board Figure 1 EVAL-ICE2QR1065Z-24W 3 List of Features Industry first IC in DIP7 package with 24W maximum output power ® 650V avalanche rugged CoolMOS with built in depletion startup cell Quasi-resonant operation Digital frequency reduction with decreasing load Cycle-by-cycle peak current limitation with foldback point correction Built-in digital soft-start Direct current sensing with internal Leading Edge Blanking Time VCC under voltage protection: IC stop operation, recover with softstart VCC over voltage protection: IC stop operation, recover with softstart Openloop/Overload protection: Auto Restart Output overvoltage protection: Latch-off with adjustable threshold Short-winding protection: Latch-off Over temperature protection: Autorestart Application Note 6 12 March 2012 EVAL-ICE2QR1065Z-24W 4 Technical Specifications Input voltage Input frequency Output voltage and current Output power Efficiency Standby power Minimum switching frequency at full load, minimum input voltage 5 85Vac~265Vac 50Hz, 60Hz 12V 2A 24W >83% at full load <100mW@no load 40kHz Circuit Description 5.1 Mains Input and Rectification The AC line input side comprises the input fuse F1 as overcurrent protection. The X2 Capacitors C1, C2 and Choke L1 form a main filter to minimize the feedback of RFI into the main supply. After the bridge rectifier BD1, together with a smoothing capacitor C3, provide a voltage of 70VDC to 380 VDC depending on mains input voltage. A 5.0 Ω NTC resistor is placed in series with input to limit the initial peak inrush current whenever the power supply is switched on when C3 is fully discharged. 5.2 Integrated MOSFET and PWM Control ICE2QR1065Z is comprised of a power MOSFET and the quasi-resonant controller; this integrated solution greatly simplifies the circuit layout and reduces the cost of PCB manufacturing. The PWM switch-on is determined by the zero-crossing input signal and the value of the up/down counter. The PWM switch-off is determined by the feedback signal VFB and the current sensing signal VCS. ICE2QR1065Z also performs all necessary protection functions in flyback converters. Details about the information mentioned above are illustrated in the product datasheet. 5.3 Snubber Network A snubber network R1, C4, R2, R16, ZD2 and D1 dissipate the energy of the leakage inductance and suppress ringing on the SMPS transformer. Due to the resonant capacitor C10 paralled to MOSFET drain souce pin, the overshoot is relatively smaller than fixed frequency flyback converter. Thus the snubber resistor can be used with a larger one which will reduce the snubber loss. 5.4 Output Stage On the secondary side, 12V output, the power is coupled out via a dual schottky diode D3. The capacitors C11 and C16 provide energy buffering followed by the L-C filters L2, C12 and C17 to reduce the output ripple and prevent interference between SMPS switching frequency and line frequency considerably. Storage capacitors C11 and C16 are designed to have an internal resistance (ESR) as small as possible. This is to minimize the output voltage ripple caused by the triangular current. 5.5 Feedback Loop For feedback, the output is sensed by the voltage divider of R10, R11 and R12 and compared to TL431 internal reference voltage. C15, C14 and R8 comprise the compensation network. The output voltage of TL431 is converted to the current signal via optocoupler IC2 and two resistors R6 and R7 for regulation control. Application Note 7 12 March 2012 EVAL-ICE2QR1065Z-24W 6 Circuit Operation 6.1 Startup Operation Since there is a built-in startup cell in the ICE2QR1065Z, there is no need for external start up resistor, which can improve standby performance significantly. When VCC reaches the turn on voltage threshold 18V, the IC begins with a soft start. The soft-start implemented in ICE2QR1065Z is a digital time-based function. The preset soft-start time is 12ms with 4 steps. If not limited by other functions, the peak voltageon CS pin will increase step by step from 0.32V to 1V finally. After IC turns on, the Vcc voltage is supplied by auxiliary windings of the transformer. 6.2 Normal Mode Operation The secondary output voltage is built up after startup. The secondary regulation control is adopted with TL431 and optocoupler. The compensation network C14, C15 and R8 constitutes the external circuitry of the error amplifier of TL431. This circuitry allows the feedback to be precisely controlled with respect to dynamically varying load conditions, therefore providing stable control. 6.3 Primary side peak current control The MOSFET drain source current is sensed via external resistor R5, R5A, R5B and R5C. Since ICE2QR1065Z is a current mode controller, it would have a cycle-by-cycle primary current and feedback voltage control which can make sure the maximum power of the converter is controlled in every switching cycle. 6.4 Digital Frequency Reduction During normal operation, the switching frequency for ICE2QR1065Z is digitally reduced with decreasing load. At light load, the MOSFET will be turned on not at the first minimum drain-source voltage time, but on the nth. The counter is in range of 1 to 7, which depends on feedback voltage in a time-base. The feedback voltage decreases when the output power requirement decreases, and vice versa. Therefore, the counter is set by monitoring voltage VFB. The counter will be increased with low VFB and decreased with high VFB. The thresholds are preset inside the IC. 6.5 Burst Mode Operation At light load condition, the SMPS enters into Active Burst Mode. At this stage, the controller is always active but the Vcc must be kept above the switch off threshold. During active burst mode, the efficiency increase significantly and at the same time it supports low ripple on Vout and fast response on load jump. For determination of entering Active Burst Mode operation, three conditions apply: .the feedback voltage is lower than the threshold of VFBEB(1.25V). Accordingly, the peak current sense voltage across the shunt resistor is 0.18; .the up/down counter is 7; .and a certain blanking time tBEB (24ms). Once all of these conditions are fulfilled, the Active Burst Mode flip-flop is set and the controller enters Active Burst Mode operation. This multi-condition determination for entering Active Burst Mode operation prevents mistriggering of entering Active Burst Mode operation, so that the controller enters Active Burst Mode operation only when the output power is really low during the preset blanking time. During active burst mode, the maximum current sense voltage is reduced from 1V to 0.34V so as to reduce the conduction loss and the audible noise. At the burst mode, the FB voltage is changing like a sawtooth between 3.0 and 3.6V. The switching frequency is set to a fix frequency of 52kHz. The feedback voltage immediately increases if there is a high load jump. This is observed by one comparator. As the current limit is 34% during Active Burst Mode a certain load is needed so that feedback voltage can Application Note 8 12 March 2012 EVAL-ICE2QR1065Z-24W exceed VLB (4.5V). After leaving active busrt mode, maximum current can now be provided to stabilize V O. In addition, the up/down counter will be set to 1 immediately after leaving Active Burst Mode. This is helpful to decrease the output voltage undershoot 7 Protection Features 7.1 Vcc under voltage and over voltage protection During normal operation, the VCC voltage is continuously monitored. When the Vcc voltage falls below the under voltage lock out level (VCCoff) or the Vcc voltage increases up to VCCovp, the IC will enter into autorestart mode. 7.2 Foldback point protection For a quasi-resonant flyback converter, the maximum possible output power is increased when a constant current limit value is used for all the mains input voltage range. This is usually not desired as this will increase additional cost on transformer and output diode in case of output over power conditions. The internal fold back protection is implemented to adjust the VCS voltage limit according to the bus voltage. Here, the input line voltage is sensed using the current flowing out of ZC pin, during the MOSFET on-time. As the result, the maximum current limit will be lower at high input voltage and the maximum output power can be well limited versus the input voltage. 7.3 Open loop/over load protection In case of open control loop, feedback voltage is pulled up with internally block. After a fixed blanking time 30ms, the IC enters into auto restart mode. In case of secondary short-circuit or overload, regulation voltage VFB will also be pulled up, same protection is applied and IC will auto restart. 7.4 Adjustable output overvoltage protection During off-time of the power switch, the voltage at the zero-crossing pin ZC is monitored for output overvoltage detection. If the voltage is higher than the preset threshold 3.7V for a preset period 100μs, the IC is latched off. 7.5 Short winding protection The source current of the MOSFET is sensed via four shunt resistors R5, R5A, R5B and R5C in parallel. If the voltage at the current sensing pin is higher than the preset threshold VCSSW of 1.68V during the on-time of the power switch, the IC is latched off. This constitutes a short winding protection. To avoid an accidental latch off, a spike blanking time of 190ns is integrated in the output of internal comparator. 7.6 Auto restart for over temperature protection The IC has a built-in over temperature protection function. When the controller’s temperature reaches 140 °C, the IC will shut down switch and enters into autorestart. This can protect power MOSFET from overheated. Application Note 9 12 March 2012 EVAL-ICE2QR1065Z-24W 8 Circuit diagram Figure 2 Schematic Application Note 10 12 March 2012 EVAL-ICE2QR1065Z-24W 8.1 PCB Topover layer Figure 3 Component Legend – View from topside Application Note 11 12 March 2012 EVAL-ICE2QR1065Z-24W 8.2 PCB Bottom Layer Figure 4 Solder side copper – View from bottom side Application Note 12 12 March 2012 EVAL-ICE2QR1065Z-24W 9 Component List Table 1– Component List Items Designator Part Type Quantity 1 BD1 DF08M, 1.5A/800V 2 C1 0.22uF/275Vac, X2, B32922C3104K000 3 C10 47pF/1000V 4 C11 1000uF/25V 5 C12 470uF/25V 6 C13 N/A 7 C14 100pF/50V, 0805, COG 8 C15 104k/50V, 0805, X7R 9 C16 1000uF/25V 10 C17 104k/50V, 0805, X7R 11 C2 0.22uF/275Vac, X2, B32922C3104K000 12 C3 47uF/400V, B43501A9476M000 13 C4 2.2nF/400V, B32529C8222K000 14 C5 2.2nF/250V, Y1, DE1E3KX222MA4BL01 15 C6 33uF/35V, B41851A7336M000 16 C7 104k/50V, 0805, X7R 17 C8 47pF/50V, 0805, COG 18 C9 102k/50V, 0805, X7R 19 D1 UF4007, 1.0A/1000V 20 D2 UF4007, 1.0A/1000V 21 D3 20A/100V, V20100SG 22 F1 1.6A, Fuse 23 HS1 heatsink 24 IC1 ICE2QR1065Z 25 IC2 PS2501 26 IC3 AZ431 27 J1 wire jumper 28 J2 wire jumper 29 J3 wire jumper 30 JP1 connector 31 JP2 connector 32 L1 2X27mH, 0.9A 33 L2 1.5uH 34 L3 short 35 NTC S236, 5Ohm 36 R1 150kOhm/2W 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Manufacturer Epcos Epcos Epcos Epcos Epcos Infineon Epcos Epcos To be contined Application Note 13 12 March 2012 EVAL-ICE2QR1065Z-24W Table 1– Component List continued Items Designator Part Type Quantity 37 R10 28kOhm, 0805, 1% 38 R11 10kOhm, 0805, 1% 39 R12 10kOhm, 0805, 1% 40 R13 N/A 41 R14 43.2kOhm, 0805, 1% 42 R15 10kOhm, 0805, 1% 43 R16 47Ohm, 1206, 1% 44 R2 47Ohm, 1206, 1% 45 R3 100Ohm, 0805 46 R4 N/A 47 R5 3.0Ohm, 0.25W, 1% 48 R5A 3.0Ohm, 0.25W, 1% 49 R5B 2.49Ohm, 0.25W, 1% 50 R5C 2.49Ohm, 0.25W, 1% 51 R6 680Ohm, 0805, 1% 52 R7 1.2kOhm, 0805, 1% 53 R8 20kOhm, 0805, 1% 54 RJ1 0Ohm, 1206, 1% 55 SG1 N/A 56 SG2 N/A 57 TR1 700uH, EE2520, PC40 58 VAR S07k275 59 ZD1 Zener diode, 22V 60 ZD2 6KE150A 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Application Note 14 Manufacturer 12 March 2012 EVAL-ICE2QR1065Z-24W 10 Transformer Construction Core and material: EE 2520, TDK PC40 (made by Wurth ) Bobbin: Vertical Version Primary Inductance, Lp=700μH, measured between pin 4 and pin 5 (Gapped to Inductance) Figure 5 – Transformer structure Figure 6 Transformer complete – top view Start 4 6 3 7 a 1 End 3 8 a 9 5 2 No. of turn 28 13 28 13 28 16 Wire size 1 x φ0.32 1 x trippleφ0.45 1 x φ0.32 1 x trippleφ0.45 1 x φ0.32 1 x φ0.32 Layer 1/3 primary secondary 1/3 primary secondary 1/3 primary Auxiliary Method Tight one layer Tight Tight one layer Tight Tight one layer Tight Table 2 wire gauge used of the transformer windings Application Note 15 12 March 2012 EVAL-ICE2QR1065Z-24W 11 Test Results 11.1 Efficiency and standby performance Table 3 – Efficiency vs. AC line voltage Vin(Vac) 85 115 230 265 Iin(A) 0.1635 0.3004 0.4282 0.5636 0.1372 0.2432 0.3451 0.4446 0.0832 0.1485 0.2102 0.2715 0.0078 0.135 0.1903 0.2447 PF 0.506 0.5554 0.5854 0.5998 0.4596 0.4987 0.5253 0.5444 0.3675 0.4065 0.4285 0.44 0.3546 0.3913 0.4124 0.4254 Pin(W) 7.036 14.2 21.336 28.75 6.954 13.955 20.85 27.89 7.321 13.89 20.72 27.47 7.456 13.98 20.81 27.61 Vout(V) 11.995 11.991 11.987 11.984 11.995 11.991 11.987 11.984 11.995 11.991 11.987 11.984 11.995 11.991 11.987 11.984 Iout(A) 0.5 1 1.5 2 0.5 1 1.5 2 0.5 1 1.5 2 0.5 1 1.5 2 Pout(W) 5.9975 11.991 17.9805 23.968 5.9975 11.991 17.9805 23.968 5.9975 11.991 17.9805 23.968 5.9975 11.991 17.9805 23.968 eff(%) 85.24019 84.44366 84.27306 83.36696 86.24533 85.92619 86.23741 85.93761 81.92187 86.32829 86.77847 87.25155 80.43857 85.77253 86.40317 86.80913 Efficiency (%) Efficiency Vs Output Current Ta = 25 Deg C. 88 87 86 85 84 83 82 81 80 0.5 1 1.5 Output Current (A) Vin=85Vac Vin=230Vac 2 Vin=115Vac Vin=265Vac Figure 7 – Efficiency vs. AC line voltage Application Note 16 12 March 2012 EVAL-ICE2QR1065Z-24W Input Power (W) Standby Power Vs Input Voltage 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 0.0695 0.0348 0.0384 85 115 0.0447 0.0744 0.0496 no load 150 180 Input Voltage (Vac) 230 265 Figure 8 Standby input power vs AC line voltage 11.2 EMI Performance Figure 9 EMI performance of 115Vac Line Application Note 17 12 March 2012 EVAL-ICE2QR1065Z-24W Figure 10 EMI performance of 115Vac Neutral Figure 11 EMI performance of 230Vac Line Application Note 18 12 March 2012 EVAL-ICE2QR1065Z-24W Figure 12 EMI performance of 230Vac Neutral Remarks: To further improve the EMI performance on 230Vac low frequency, it can increase the capacitance on the XCAP. 12 Waveforms and scope plots 12.1 Startup at 85Vac and 24W load Figure 13 Startup @ 85Vac Figure 14 Startup @ 265Vac Ch1 VCC Supply Voltage Ch1 VCC Supply Voltage Ch2 Zero Crossing Voltage, VZC Ch2 Zero Crossing Voltage, VZC Ch3 Current Sense Voltage, VCS Ch3 Current Sense Voltage, VCS Ch4 Feedback Voltage, VFB Ch4 Feedback Voltage, VFB Test Condition: 85Vac input, 2A Load Test Condition: 265Vac input, 2A Load Application Note 19 12 March 2012 EVAL-ICE2QR1065Z-24W 12.2 Soft-Start with 24W Load Figure 15 Soft-Start @ 85Vac Figure 16 Soft-Start @ 265Vac Ch1 VCC Supply Voltage Ch1 VCC Supply Voltage Ch2 Zero Crossing Voltage, VZC Ch2 Zero Crossing Voltage, VZC Ch3 Current Sense Voltage, VCS Ch3 Current Sense Voltage, VCS Ch4 Feedback Voltage, VFB Ch4 Feedback Voltage, VFB Test Condition: 85Vac input, 2A Load Test Condition: 265Vac input, 2A Load 12.3 Load Transient Response Figure 17 AC output ripple overshoot Figure 18 AC output ripple undershoot Ch1 Output Current, Iout Ch1 Output Current, Iout Ch4 Output Voltage, Vout Ch4 Output Voltage, Vout Test Condition: Load 100% to 10% 100Hz, 0.4A/us Test Condition: Load 10% to 100% 100Hz, 0.4A/us Measured with decouple capacitor 0.1uF, and 10uF Measured with decouple capacitor 0.1uF, and 10uF Application Note 20 12 March 2012 EVAL-ICE2QR1065Z-24W 12.4 Burst Mode Operation Figure 19 Entering Burst Mode Operation Figure 20 Leaving Burst Mode Operation Ch1 Feedback Voltage, VFB Ch1 Feedback Voltage, VFB Ch2 Zero Crossing Voltage, VZC Ch2 Zero Crossing Voltage, VZC Ch3 Current Sense Voltage, VCS Ch3 Current Sense Voltage, VCS Ch4 Output Voltage, Vo Ch4 Output Voltage, Vo th Test Condition: 265Vac, Load changed fr. 6 ZC to 0A Test Condition: 265Vac, Load changed fr. 0A to 2A Figure 21 Active Burst Mode Operation Figure 22 Active Burst Mode Operation Ch1 Feedback Voltage, VFB Ch1 Feedback Voltage, VFB Ch2 Zero Crossing Voltage, VZC Ch2 Zero Crossing Voltage, VZC Ch3 Current Sense Voltage, VCS Ch3 Current Sense Voltage, VCS Ch4 Output Voltage, Vo Ch4 Output Voltage, Vo Test Condition: 85Vac, under BMO Test Condition: 265Vac, under BMO Application Note 21 12 March 2012 EVAL-ICE2QR1065Z-24W 12.5 Protection modes Figure 23 VCC Over-voltage Protection Figure 24 Over Load/ Open Loop Protection Ch1 Feedback Voltage, VFB Ch1 Feedback Voltage, VFB Ch2 Zero Crossing Voltage. VZC Ch2 Zero Crossing Voltage. VZC Ch3 Current Sense Voltage, VCS Ch3 Current Sense Voltage, VCS Ch4 VCC Supply Voltage Ch4 VCC Supply Voltage Test Condition: open the zener clamping with Test Condition: Load Stepping fr. 2A to 3A overload at high-line Figure 25 Output Over-voltage Protection Figure 26 Drain Source Voltage @ low line Ch1 Feedback Voltage, VFB Ch2 Drain-source voltage, VDS Ch2 Zero Crossing Voltage. VZC Ch3 Current Sense Voltage, VCS Ch3 Current Sense Voltage, VCS Test Condition: 85Vac, Full Load (2A) Ch4 VCC Supply Voltage Test Condition: change the ZC resistor divider ratio Application Note 22 12 March 2012 EVAL-ICE2QR1065Z-24W Figure 27 Drain Source Voltage @ low line Ch2 Drain-source voltage, VDS Ch3 Current Sense Voltage, VCS Test Condition: 265Vac, Full Load (2A) 13 References [1] ICE2QR1065Z datasheet, Infineon Technologies AG, 2011 [2] ICE2Qxx65/80x Quasi Resonance CoolSET Design Guide (ANPS0053), Infineon Technologies AG, 2010 [3] Design Tips for flyback converters using the Quasi-Resonant (ANPS0005), Infineon Technologies AG, 2006 [4] Converter Design Using the Quasi-Resonant PWM Controller ICE2QS01 (ANPS0003), Infineon Technologies AG, 2006 [5] Determine the Switching Frequency of Quasi-Resonant Flyback Converters Designed with ICE2QS01 (ANPS0004), Infineon Technologies AG, 2006 Application Note 23 12 March 2012