Application Note, V1.0, May 2010 AN-EVALSF3-ICE3B0365J 5W 2 outputs (5V & 18V) DC/DC SMPS Demo Board with CoolSET® F3 ICE3B0365J Power Management & Supply N e v e r s t o p t h i n k i n g . Edition 2010-05-19 Published by Infineon Technologies Asia Pacific, 8 Kallang Sector, 349282 Singapore © Infineon Technologies AP 2010. All Rights Reserved. Attention please! The information herein is given to describe certain components and shall not be considered as a guarantee of characteristics. Terms of delivery and rights to technical change reserved. We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding circuits, descriptions and charts stated herein. Information For further information on technology, delivery terms and conditions and prices please contact your 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 your nearest Infineon Technologies Office. Infineon Technologies Components may only be used in life-support devices or systems 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 ® 5W 2 outpus (5V & 18V) DC/DC Demo board with CoolSET F3 ICE3B0365J Revision History: 2010-05 Previous Version: none Page V1.0 Subjects (major changes since last revision) ® 5W 2 outputs (5V & 18V) DC/DC Demo Board with CoolSET F3 ICE3B0365J: License to Infineon Technologies Asia Pacific Pte Ltd Kyaw Zin Min Kok Siu Kam Eric He Yi Jeoh Meng Kiat 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] AN-PS0046 5W 2 outputs DC/DC Demo board using ICE3B0365J Table of Contents Page 1 Abstract..........................................................................................................................................5 2 Evaluation board ...........................................................................................................................5 3 List of features...............................................................................................................................6 4 Technical specifications...............................................................................................................6 5 Description of function and components...................................................................................7 6 6.1 6.2 PCB layout .....................................................................................................................................9 Top side...........................................................................................................................................9 Bottom side .....................................................................................................................................9 7 Component list ............................................................................................................................10 8 Transformer construction ..........................................................................................................11 9 9.1 9.2 9.3 9.4 Test results ..................................................................................................................................12 Efficiency .......................................................................................................................................12 Input standby power ......................................................................................................................12 Line regulation...............................................................................................................................14 Load regulation .............................................................................................................................14 10 10.1 10.2 10.3 10.4 Waveforms and scope plots ......................................................................................................15 Start up at low and high DC input voltage and max. load.............................................................15 Soft start at low and high DC input voltage and max. load ...........................................................15 Frequency jittering.........................................................................................................................16 Entering active burst mode ...........................................................................................................16 11 References ...................................................................................................................................17 Application Note 4 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 1 Abstract ® This application note describes a non-isolated flyback converter power supply utilizing IFX F3 CoolSET ICE3B0365J. The application demo board works with an input voltage from 275VDC to 375VDC and it has two output voltages, 5V and 18V with simple single transistor control regulation. The sum of the output power is up to 5W shared to both outputs. It is operated in Discontinuous Conduction Mode (DCM) and is running at 67 kHz switching frequency with jittering mode. It is especially suitable for auxiliary power supply of consumer home appliance such as white goods, air conditioner, refrigerator, cookers, etc. The particular features needs to be stressed are the best in class low standby power and the good EMI performance. 2 Evaluation board Figure 1 – EVALSF3-ICE3B0365J This document contains the list of features, the power supply specification, schematic, bill of material and the transformer construction documentation. Typical operating characteristics such as performance curve and scope waveforms are showed at the rear of the report. Application Note 5 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 3 List of features ® 650V avalanche rugged CoolMOS with built in switchable Startup Cell Active Burst Mode for lowest Standby Power @ light load controlled by Feedback signal BiCMOS technology provide wide Vcc voltage range Fast load jump response in Active Burst Mode 67kHz fixed switching frequency Auto Restart Mode for Over temperature protection, Overvoltage protection, Overload protection, Open Loop protection and VCC Undervoltage protection Blanking Window for short duration max current User defined Soft Start Max Duty Cycle 72% Propagation delay compensation provide accurate primary current limit Frequency jittering for low EMI 4 Technical specifications Input voltage 275Vdc~375Vdc Output 1 voltage and current 5V +/- 5%, (0.2A) Output 2 voltage and current 18V +/- 10%, (0.22A) Output power 5W Acitve mode average efficiency (25%, 50%, 75%, 100%) >80% Switching frequency 67kHz Application Note 6 2010-05-19 Application Note 7 R2 5R1 Vcc 1uF C5 SoftS CS 0.1uF C3 FB C6 1nF IC1 ICE3B0365J GND DRAIN 33uF/35V C4 D1 UF4006 22R R3 C2 2.2nF/400V 4 Nov 2009 5W 18V, 5V Non-isolated flyback SMPS converter using ICE3B0365J GND C1 10uF/400V 10uF R1 330k 8 5 7 Q1 BC547B 2.2nF C7 1N4148 D2 5.67mH(195:12:40) 1 3 T1 2K R4 ZD1 5V1 C8 47uF/25V Res2 22R R5 D4 C9 47uF/25V UF4003 D3 UF4005 Gnd 5V/0.2A 18V/0.22A 5 Gnd DC(275~375)V 4 5W 2 outputs DC/DC Demo board using ICE3B0365J Description of function and components Figure 2 – 5W 2 outpus (18V & 5V) ICE3B0365J power supply schematic 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J The circuit, shown in Figure 2, details a 5V & 18V, 5W non-isolated flyback converter module that operates from an DC input voltage range of 275Vdc to 375Vdc. Since there is a built-in startup cell in the ICE3B0365J, there is no need for external start up resistor. The startup cell is connecting the drain pin of the IC. Once the voltage is built up at the Drain pin of the ICE3B0365J, the startup cell will charge up the Vcc capacitor C3 and C4. When the Vcc voltage exceeds the UVLO at 18V, the IC starts up. Then the Vcc voltage is bootstrapped by the 18V winding of T1 to sustain the operation. The ICE3B0365J (IC1) begins a soft start cycle (programmed by C5). In parallel, the both output voltages across C8 and C9 rise until the zener voltage of ZD1 is reached. ZD1 and R4 forms the voltage sense circuit and the Q1 acts as an error amplifier with VBE as the reference voltage and C7 is the loop gain compensator. R1, C2 and D1 form a clamper snubber circuit on the primary transformer side. This circuit limits the excess transient voltage rising on the switching transistors drain caused by the transformers leakage inductance after switching off. R2 is the current sense resistor used in two ways: The voltage drop across this resistor provides the current ramp to be compare with FB signal by the PWM comparator of the current mode regulation circuit of the IC. Additionally, this value is compared with a fix VCS_max threshold to prevent any overcurrent condition in each switching cycle. The SoftS capacitor (CSoftS), C5 can be used to program 3 functions; 1. Soft Start time : t Softs = 0.793 ⋅ C SoftS * RSoftS = 35ms , where CSoftS=1uF, RSoftS=45KΩ 2. Over load blanking time / enter burst mode blanking time : where CSoftS=1uF, RSoftS=45KΩ 3. Frequency jittering period : t blanking = 0.47 ⋅ C SoftS * RSoftS = 21ms , t jittering = 3200 ⋅ C SoftS = 3.2ms , where CSoftS=1uF In order to obtain the lowest standby power performance, the IC provides the active burst mode. When the output loading decreases, the feeback voltage decreases at the same time. When the feedback, FB voltage drops below 1.35V, the system will enter the “Active burst mode”; standby mode. In the standby mode, the only active part in the IC is the FB and thus the IC has very limited power consumption. Together with the active burst mode, the standby power can be reduced tremendously. Operation of the active burst mode is as below. 1. Enter burst mode condition : VFB < 1.35V and after blanking time (programmed by CSoftS) 2. Working in burst mode : Burst “On” (with switching pulses) when VFB reaches 3.6V and Burst “Off” ( no switching pulse) when VFB drops to 3.0V, at the same time Vcs reduces to 0.32V ( Note the Vcc voltage must be kept above 10.3V to maintain IC on ) 3. Leave burst mode : VFB reaches 4.5V The IC also implements with frequency jittering to achieve good EMI performance. The jittering frequency is ±4% of the switching frequency and the frequency jittering period can be programmed by the CSoftS. Besides, there are various built-in protections (auto restart mode) to protect the system from damages. The protection conditions are as below. Protection function Failure condition Vcc Over-voltage Vcc > 20.5V & VFB > 4.5V & VSoftS > 4.0V Auto Restart Over-temperature (controller junction) TJ > 140°C Auto Restart Over-load / Open loop / output short circuit VFB > 4.5V and VSoftS > 4.0V Auto Restart Vcc Under-voltage / short Opto-coupler Vcc < 10.3V Auto Restart Application Note Protection Mode 8 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 6 6.1 PCB layout Top side Figure 4 – Top side component legend 6.2 Bottom side Figure 5 – Bottom side copper Application Note 9 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 7 Component list No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Designator C1 C2 C3 C4 C5 C6 C7 C8,C9 D1 D2 D3 D4 IC1 Q1 R1 R2 R3,R5 R4 T1 ZD1 Application Note Component description 10uF/400V 2.2nF/400V 0.1uF 33uF/35V 1uF 1nF 2.2nF 47uF/25V UF4006 1N4148 UF4005 UF4003 ICE3B0365J BC547B 330k(1W,5%) 5R1(0.5W,1%) 22R 2k 5670uH(195:12:40) 5V1 10 Part No. Manufacturer RPER71H104K2K1A03B B41851A7336M000 MURATA EPCOS RPER71H102K2K1A03B MURATA B41821A5476M000 EPCOS ICE3B0365J INFINEON E16/8/5,N87 EPCOS 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 8 Transformer construction Core: E16/8/5, N87(EPCOS) Bobbin: vertical Version Primary Inductance, Lp=5.67mH, measured between pin 4 and pin 1 (Gapped to inductance) Transformer structure: 4 7 3 5 8 1 Pin 1 Pin 2 Pin 3 Pin 4 TOP VIEW Vertical bobbin Pin 8 Pin 7 Pin 6 Pin 5 Figure 6 – Transformer structure and top view of transformer complete Wire size requirement: Start 3 5 8 4 Application Note Stop 1 7 5 3 No. of turns 65 28 12 130 Wire size 1XAWG#38 1XAWG#27 1XAWG#27 1XAWG#38 11 Layer /2 Primary Secondary2 Secondary1 1 /2 Primary 1 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 9 Test results 9.1 Efficiency Active-Mode Efficiency versus DC Input Voltage Efficiency [ % ] 88.00 85.1 86.00 85.5 85.3 85.4 84.00 83.1 82.4 81.1 82.00 80.6 80.00 275 300 350 375 DC Input Voltage [ Vdc ] Full load Ef ficiency Average Eff iciency(25%,50%,75%,100%) Figure 7 – Efficiency vs. DC input voltage Active-Mode Efficiency versus Output Power 90.00 Efficiency [ % ] 85.4 85.00 79.5 80.00 84.3 83.5 83.1 80.0 78.1 85.1 83.3 75.8 75.00 73.6 73.0 70.00 1.0 1.3 1.5 2.6 3.9 5.1 Onput Power [ W ] 275Vdc 375Vdc Figure 8 – Efficiency vs. output power @ low and high DC input voltage 9.2 Input standby power Stanby Power @ no-load versus DC Input Voltage Input Power [ mW] 50 40 30 17.450 17.590 17.590 21.34 20 10 0 275 300 350 375 DC Input Voltage [ Vdc ] Po = 0W Figure 9 – Input standby power @ no load vs. DC input voltage (measured by Yokogawa WT210 power meter - integration mode) Application Note 12 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J Standby Efficiency & Input Power Vs DC Input Voltage 0.776 0.78 69.88 69.80 0.772 Input Power (W) 70.20 69.40 69.36 0.768 0.767 0.764 69.00 68.60 0.760 0.756 68.20 68.07 0.753 0.752 Efficiency (%) 0.780 67.80 0.748 0.747 0.744 67.40 67.25 67.00 0.740 275 300 350 375 DC Input Voltage(Vdc) Input Power at 0.5W load Efficiency at 0.5W Load Figure 10 – Input standby power & efficiency @ 0.5W ( 0.25W(5V)+0.25W(18V) ) vs. DC input voltage (measured by Yokogawa WT210 power meter - integration mode) Input versus DC Input Voltage Input Power [ W ] 2.500 1.86 2.000 1.500 1.000 1.36 1.94 1.89 1.40 1.37 1.98 1.41 0.75 0.75 0.77 0.78 275 300 350 375 0.500 0.000 DC Line Input Voltage [ Vdc ] I/P pow er @ 0.5W Load I/P Pow er @ 1W Load I/P Power @ 1.5W Load Figure 11 – Light load input power vs. DC input voltage ( 0.5W : 0.25W(5V)+0.25W(18V), 1W : 0.25(5V)+0.75W(18V), 1.5W : 0.25W(5V)+1.25W(18V) ) Efficiency versus DC Input Voltage 83.11 85.00 81.79 Efficiency [ % ] 79.68 80.00 75.00 75.8 69.9 70.00 75.2 73.6 69.4 68.1 78.07 73.0 67.3 65.00 60.00 275 300 350 375 DC Line Input Voltage [ Vdc ] Ef ficiency @ 0.5W Load Eff iciency @ 1W Load Efficiency @ 1.5W Load Figure 12 – Light load Efficiency vs. DC input voltage ( 0.5W : 0.25W(5V)+0.25W(18V), 1W : 0.25(5V)+0.75W(18V), 1.5W : 0.25W(5V)+1.25W(18V) ) Application Note 13 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 9.3 Line regulation Line Regulation @ max. Load vs DC input Voltage 5V output 5.15 5.05 4.95 18.70 18.70 18.71 5.06 5.06 5.07 18.72 18.50 5.07 18.00 4.85 17.50 4.75 17.00 275 300 350 18V output 19.00 5.25 375 DC input voltage(Vdc) 5V @ max. load 18V @ max. load Figure 13 – Line regulation @ full load vs. DC input voltage 9.4 Load regulation Load Regulation Vout vs Output Power 5.25 5V output 19.45 5.05 5V @ 0.05A & 18V @ 0.055A 5V @ 0.1A & 18V @ 0.11A 5.11 5.10 5.08 5V @ 0.15A & 18V @ 0.165A 5V @ 0.2A & 18V @ 0.22A 19.50 5.06 5.08 19.00 4.95 18.76 18.79 18.75 4.85 18.72 4.75 18V output 5.15 20.00 5V @ 0.05A & 18V @ 0.014A 18.50 18.00 0.5 1.3 2.6 3.9 5.1 DC input voltage(Vdc) 5V o/p @ 275Vdc 18V o/p @ 275Vdc Figure 14 – Load regulation Vout vs. output power Application Note 14 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 10 Waveforms and scope plots All waveforms and scope plots were recorded with a LeCroy 6050 oscilloscope 10.1 Start up at low and high DC input voltage and max. load 873ms 873ms Channel 1; C1 : Current sense voltage (VCS) Channel 2; C2 : Supply voltage (VCC) Channel 3; C3 : Feedback voltage (VFB) Channel 4; C4 : SoftS voltage (VsoftS) Channel 1; C1 : Current sense voltage (VCS) Channel 2; C2 : Supply voltage (VCC) Channel 3; C3 : Feedback voltage (VFB) Channel 4; C4 : SoftS voltage (VsoftS) Startup time = 873ms Startup time = 873ms Figure 15 – Startup @ 275Vdc & max. load Figure 16 – Startup @ 375Vdc & max. load 10.2 Soft start at low and high DC input voltage and max. load 43ms 43ms Channel 1; C1 : Current sense voltage (VCS) Channel 2; C2 : Supply voltage (VCC) Channel 3; C3 : Feedback voltage (VFB) Channel 4; C4 : SoftS voltage (VsoftS) Channel 1; C1 : Current sense voltage (VCS) Channel 2; C2 : Supply voltage (VCC) Channel 3; C3 : Feedback voltage (VFB) Channel 4; C4 : SoftS voltage (VsoftS) Soft Star time = 43ms Soft Star time = 43ms Figure 17 – Soft Start @ 275Vdc & max. load Figure 18– Soft Start @ 375Vdc & max. load Application Note 15 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 10.3 Frequency jittering 63 kHz 68 kHz 63 kHz 68 kHz Channel 1; C1 : Drain voltage (VDrain) Channel 1; C1 : Drain voltage (VDrain) Frequency jittering from 63 kHz ~ 68 kHz, Jitter period is set at 4ms internally , VDrain_PP=475V Frequency jittering from 63kHz ~ 68 kHz, Jitter period is set at 4ms internally, VDrain_PP=575V Figure 19 – Frequency jittering @ 275Vdc and max. load Figure 20 – Frequency jittering @ 375Vdc and max. load 10.4 Entering active burst mode 19ms 19ms Channel 1; C1 : Current sense voltage (VCS) Channel 2; C2 : Supply voltage (VCC) Channel 3; C3 : Feedback voltage (VFB) Channel 4; C4 : SoftS voltage (VsoftS) Blanking time to enter burst mode : 19ms (load step down from 4A to 0.2A) Figure 21 – Entering Active burst mode @ 275Vdc Application Note Channel 1; C1 : Current sense voltage (VCS) Channel 2; C2 : Supply voltage (VCC) Channel 3; C3 : Feedback voltage (VFB) Channel 4; C4 : SoftS voltage (VsoftS) Blanking time to enter burst mode : 19ms (load step down from 4A to 0.2A) Figure 22 – Entering Active burst mode @ 375Vdc 16 2010-05-19 5W 2 outputs DC/DC Demo board using ICE3B0365J 11 References ® [1] Infineon Technologies, Datasheet “CoolSET -F3 ICE3BXX65J Off-Line SMPS Current Mode Controller ® with integrated 650V CoolMOS and Startup cell” [2] Luo Junyang, Jeoh Meng Kiat, Lim Chee Siong Simon, Kok Eric, Infineon Technologies, Design Guide ® “ICE3AXXX/ICE3BXXX CoolSET - F3 Design Guide” [3] Harald Zoellinger, Rainer Kling, Infineon Technologies, Application Note “AN-SMPS-ICE2xXXX-1, ® CoolSET ICE2xXXXX for Off-Line Switching Mode Power supply (SMPS )” Application Note 17 2010-05-19