ICL8201 A C / D C B u c k C o n t r o l l e r wi t h P F C f o r L E D Lamps Dat a She et Revision V2.0 2015-05-25 Po wer Ma nage m ent & M ul ti m ark et Edition 2015-05-25 Published by Infineon Technologies AG, 81726 Munich, Germany. © 2015 Infineon Technologies AG All Rights Reserved. LEGAL DISCLAIMER THE INFORMATION GIVEN IN THIS APPLICATION NOTE IS GIVEN AS A HINT FOR THE IMPLEMENTATION OF THE INFINEON TECHNOLOGIES COMPONENT ONLY AND SHALL NOT BE REGARDED AS ANY DESCRIPTION OR WARRANTY OF A CERTAIN FUNCTIONALITY, CONDITION OR QUALITY OF THE INFINEON TECHNOLOGIES COMPONENT. THE RECIPIENT OF THIS APPLICATION NOTE MUST VERIFY ANY FUNCTION DESCRIBED HEREIN IN THE REAL APPLICATION. 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) WITH RESPECT TO ANY AND ALL INFORMATION GIVEN IN THIS APPLICATION NOTE. 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. ICL8201 AC/DC Buck Controller with PFC for LED Lamps Trademarks of Infineon Technologies AG AURIX™, C166™, CanPAK™, CIPOS™, CIPURSE™, EconoPACK™, CoolMOS™, CoolSET™, CORECONTROL™, CROSSAVE™, DAVE™, DI-POL™, EasyPIM™, EconoBRIDGE™, EconoDUAL™, EconoPIM™, EconoPACK™, EiceDRIVER™, eupec™, FCOS™, HITFET™, HybridPACK™, I²RF™, ISOFACE™, IsoPACK™, MIPAQ™, ModSTACK™, my-d™, NovalithIC™, OptiMOS™, ORIGA™, POWERCODE™; PRIMARION™, PrimePACK™, PrimeSTACK™, PRO-SIL™, PROFET™, RASIC™, ReverSave™, SatRIC™, SIEGET™, SINDRION™, SIPMOS™, SmartLEWIS™, SOLID FLASH™, TEMPFET™, thinQ!™, TRENCHSTOP™, TriCore™. Other Trademarks Advance Design System™ (ADS) of Agilent Technologies, AMBA™, ARM™, MULTI-ICE™, KEIL™, PRIMECELL™, REALVIEW™, THUMB™, µVision™ of ARM Limited, UK. AUTOSAR™ is licensed by AUTOSAR development partnership. Bluetooth™ of Bluetooth SIG Inc. CAT-iq™ of DECT Forum. COLOSSUS™, FirstGPS™ of Trimble Navigation Ltd. EMV™ of EMVCo, LLC (Visa Holdings Inc.). EPCOS™ of Epcos AG. 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VERILOG™, PALLADIUM™ of Cadence Design Systems, Inc. VLYNQ™ of Texas Instruments Incorporated. VXWORKS™, WIND RIVER™ of WIND RIVER SYSTEMS, INC. ZETEX™ of Diodes Zetex Limited. Last Trademarks Update 2011-11-11 Data Sheet 3 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Revision History Major changes since previous revision Date Version 2015-05-25 2.0 Changed By Change Description First Release We Listen to Your Comments Is there any information in this document that you feel is wrong, unclear or missing? Your feedback will help us to continuously improve the quality of our documentation. Please send your proposal (including a reference to this document title/number) to: [email protected] Data Sheet 4 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Table of Contents Revision History ....................................................................................................................................................4 Table of Contents ..................................................................................................................................................5 1 Block Diagram ...................................................................................................................................8 2 2.1 2.2 2.3 2.4 IC and Application Feature Overview..............................................................................................9 Application Feature SET .....................................................................................................................9 IC Feature SET ...................................................................................................................................9 Regulation Feature SET......................................................................................................................9 Protection Feature SET.....................................................................................................................10 3 3.1 3.2 3.3 Pin Configuration and Functionality .............................................................................................12 Pin Configuration with PG-SOT23-6-1 ..............................................................................................12 Package ............................................................................................................................................12 Pin Description ..................................................................................................................................12 4 4.1 4.2 4.2.1 4.2.2 4.2.3 4.2.4 4.2.5 4.2.6 4.2.7 4.2.8 4.2.9 4.2.10 4.3 4.3.1 4.3.1.1 4.3.1.2 4.3.1.3 4.3.1.4 4.3.1.5 4.3.2 4.3.2.1 4.3.2.2 4.3.2.3 4.3.3 4.3.4 4.3.4.1 4.3.4.2 Functional Description ...................................................................................................................14 Typical Application Circuit .................................................................................................................14 Internal Functional Description..........................................................................................................15 VCC Pre-Charging and Typical VCC voltage profile During Start-up .............................................15 Soft Start ......................................................................................................................................16 Normal Regulation Operation ......................................................................................................17 Zero Current Detection ................................................................................................................17 Peak Detection.............................................................................................................................19 Voltage to Current Converter .......................................................................................................20 ON time generation ......................................................................................................................20 How to calculate output average current .....................................................................................21 Leading Edge Blanking ................................................................................................................21 Driver Stage .................................................................................................................................21 System Functional description ..........................................................................................................22 Start-Up behaviour .......................................................................................................................22 Start-Up: Into Normal Operation .............................................................................................22 Start-Up: Soft-Start Phase ......................................................................................................23 Start-Up: Short Output ............................................................................................................24 Start-Up: Floating Load Protection .........................................................................................25 Start-Up and Run Mode: Short Winding Protection ................................................................26 Run Mode behaviour....................................................................................................................27 Typical Curves during RUN Mode ..........................................................................................27 Run Mode: Short Output .........................................................................................................28 Run Mode: Floating Load Protection ......................................................................................29 Intelligent Over-Temperature Protection (iOTP) ..........................................................................30 IC Working and Typical BUCK Curves ........................................................................................31 Critical Conduction operation with Constant TON Time and variable Frequency ....................31 Typical Curves of a BUCK Converter .....................................................................................32 5 5.1 5.2 Absolute Maximum Ratings and thermal Characteristics ..........................................................33 Absolute Maximum Ratings ..............................................................................................................33 Thermal Characteristics ....................................................................................................................34 6 Electrical Characteristics ...............................................................................................................35 Data Sheet 5 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps 6.1 6.2 DC Characteristics ............................................................................................................................35 Switching Characteristics ..................................................................................................................36 7 Application Example .......................................................................................................................37 8 Bill of Materials................................................................................................................................38 9 Package Outline ..............................................................................................................................39 Data Sheet 6 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps ICL8201 – Single-Stage Floating Buck Controller IC with Power Factor Correction for LED Lamps Product Highlights Low external component count for smallest form factors and easy design-in IC concept allows standard single chokes without auxiliary winding True universal AC line input voltage or DC supply Compensation of sudden line input voltage changes Supports wide output voltage Capable of providing an average LED output current up to 800 mA at 50% Duty Cycle Typical ± 5% output current accuracy over line, load and temperature variation Supports PF > 90% / iATHD < 20% over a wide line input voltage range System efficiency up to 90% Thermally-optimized package PG-SOT23-6-1 for small form factor designs Smooth start-up with minimized current overshoot Advanced cascode topology eliminates the requirement of high voltage startup cell External power switch supports fast time-to-light and high operating temperature Operation specified for junction temperature up to Tj = 150 °C IC Features - Critical Conduction operation mode without detection winding Constant tON operation with variable frequency 40 kHz to 150 kHz Integrated low-side MOSFET for rated peak current up to 2.65A Digital soft-start Fully integrated protection: Short load Support open load Short winding at buck inductor Over-current protection (power limitation) Intelligent Over-Temperature Protection @ Tjmax = 150 °C VCC Under-Voltage Lock-Out Short-to-GND of CS pin and Con pin Floating CS pin and Con pin Phase cut dimmer-safe Target Applications A-lamps GU10 lamps PAR lamps Candelabra lamps Down lights T8 lamps Data Sheet 7 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Block Diagram 1 VCS 1 Block Diagram Bandgap UVLO & internal high-frequency oscillator bias Valley detection GND 2 6 DRAIN Timing control S Q R Q Internal NMOS softstart Constant on time 5 GND Overcurrent CON 3 Peak detection sample & hold Logic control Figure 1 Data Sheet V-to-I converter COMP 1 Thermal protection 4 VCC Vref Internal Block Diagram 8 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps IC and Application Feature Overview 2 IC and Application Feature Overview 2.1 Application Feature SET Table 1 Application Feature SET Single Choke Transformer Free Support the use of Standard Chokes BOM Count < 22 Components Form Factor Fit into: E14 / GU10 Sockets AC Line IN: Wide Range Opportunity 80VACIN - 325VACIN Real Wide Range Design / Regulation of sudden Line Jumps Star up behaviour Smooth Start Up of LED Current Expected Efficiency 86% up to 90% Maximum Junction Temperature TJunctionMAX = 150°C Maximum Ambient Temperature TAmbientMAX = 105°C 2.2 Temperature of PCB inside Bulb IC Feature SET Table 2 IC Feature SET IC Operation MODE Critical Conduction / DCM Op. / Constant tON DCM Operation with Critical Conduction Operation Package PG-SOT23-6-1 / Rthja = 264K/W / 6 PINs No Cooling Area ON PCB Active PINs 4 active PINs + 2 GND VCC / Con / VCS / DRAIN / GND MOS Stage inside RDSON25°C = 0.370 Ω / Low Voltage Low Side MOSFET Integrated ISWpeak= 0.5A Operating Condition VCCOp = 10V / ICCOp around 0.82mA @ active Gates for Applications up to 15W fRUN 40kHz up to 150kHz Operating Frequency Range Soft-Start 24ms Digital Internal System Accuracy (overall) 2.3 < 5% Up to TJmax = 150°C Stable Overall Accuracy in a wide Temperature Range up to TJ Regulation Feature SET Table 3 Regulation Feature SET Line Regulation ILED Variation < ± 5% 85V < VACINnom < 325V Load Regulation ILED Variation < ± 5% VFLED from 20V up to 60% VIN Constant OUTPUT Current Operation ILED Variation < ± 5% Data Sheet 9 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps IC and Application Feature Overview Compensation of Magnetic Impact LP Variation ± < 20% Power Factor Supports : EN61000-3-2 > 70% up to ~ 99% iATHD Supports : EN61000-3-2 < 20% Harmonic Distortion Supports : EN61000-3-2 PASS Lightning Surge Supports: EN61000-4-5 PASS EMI Supports: EN55015 PASS 2.4 Protection Feature SET Table 4 Protection Feature SET VCSth < 0.1V VCS Short (PIN 1) to GND & VDrain > 0.25V during tON Start UP / RUN Mode Latch Start UP / RUN Mode Latch Start UP Latch Start UP Latch tBlanking = 200ns Blanking Time VCSth > 1.2V & VCS Open (PIN 1) TBlanking=100ns After LEB triggered With 3 continuous switching cycle VCon Short (PIN 3) to GND VConth < 0.2V & tBlanking=5ms VCon > 1.5V VCon OPEN (PIN 3) & tBlanking = 18µs VCSth < 0.12V & Floating Load Protection (FLP) Start UP: After soft-start with 160ms blanking time Start UP / RUN Mode Disabled during OTP Latch Run MODE: After: 160ms Blanking Time VCSth > 0.62V & Short OUTPUT No Zero current Detection for continuous Start UP / RUN Mode Latch Start UP / RUN Mode Latch RUN Mode Limiting 126 Switching Cycles VCSth > 1.2V Short Winding (Main Choke) & TBlanking=100ns After LEB triggered With 3 continuous switching cycle Power Limitation Data Sheet VCSth = 0.9V Cycle by Cycle 10 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps IC and Application Feature Overview iOTP Intelligent Over Temperature Protection TJ > 150°C ± 10°C Start UP / RUN Mode IOUT from 100% to 50% De-rating within 7 digital Steps VCC Under Voltage (UVLO) VCC < 6.0V Start UP / RUN Mode Auto Restart Dimmer Input Acceptable UVLO Start UP / RUN Mode Auto Restart iATHD Feature On Time Reduction RUN Mode Disabled during OTP N.A. VCSth = 0.1V till 3 ms Soft Start digital 24 ms VCSth = 0.2V till 6 ms Start UP VCSth = 0.3V till 9 ms Limiting VCSth = 0.4V till 24 ms Data Sheet 11 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Pin Configuration and Functionality 3 Pin Configuration and Functionality 3.1 Pin Configuration with PG-SOT23-6-1 Table 5 Pin configuration Pin Symbol Function 1 VCS Current Sense 2 GND Ground 3 Con Constant Current / Output Current Ripple 4 VCC Supply Voltage 5 6 GND DRAIN Ground DRAIN of integrated MOSFET 3.2 Package Figure 2 Pin configuration PG-SOT23-6-1 (top view) 3.3 Pin Description Vcs (current sense, pin 1) This pin is directly connected to the shunt resistor, which is located between the source terminal of the integrated low-side MOSFET and ground. Internal clamping structures and filtering measures allow sensing of the source current for the low-side power MOSFET without additional filter components. This pin is for power limitation, output average current regulation & the integrated protection features. GND (ground, pin 2) This pin is connected to ground and represents the ground level of the IC for the supply voltage, gate drive and sense signals. Con (constant current, pin 3) Regulate the constant current in the output stage of the Floating BUCK converter. Data Sheet 12 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Pin Configuration and Functionality Vcc (supply voltage, pin 4) This pin provides the power supply of the ground-related section of the IC. There is a UVLO turn-on threshold at 7.5 V (VCC.ON) and a UVLO turn-off threshold at 6.0 V (VCC.OFF). The maximum VCC supply voltage level is 18.0 V. The chip supply current is typically at IVCC = 0.82 mA. GND (ground, pin 5) This pin is connected to ground and represents the ground level of the IC for the supply voltage, gate drive and sense signals. DRAIN (DRAIN, pin 6) This pin is connected to the drain of the internal low side MOSFET. It is also used for protection features. Data Sheet 13 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4 Functional Description 4.1 Typical Application Circuit Figure 3 Application Circuit of a LED Driver in a Floating BUCK Topology Description The ICL8201 is a cascode structure current mode controller for non-isolated single-choke floating BUCK topologies. The device is tailored for LED applications and provides constant current operation with low output current ripple in a real universal line input voltage range as well as load compensation for a wide output voltage range. The low PIN count PG-SOT23-6-1 package supports small form factor and low-cost designs. The high level of integration enables a minimum of effort for addition of external components. The ICL8201 control concept supports DC and AC input as well as high Power Factor Correction (PFC), high efficiency levels and reduced EMI designs in critical conduction operation mode without zero crossing detection winding. Along with outstanding integrated regulation and protection features, the cascode arrangement simplifies VCC supply of the IC, that eliminates the need of a depletion MOS. The regulation is done without detecting the AC line input voltage or sensing the output voltage. All these features are implemented with a minimum amount of external components. The device operates in a wide junction temperature range from -25°C to 150°C. The highly efficient integrated low-voltage MOSFET will eliminate the need for any additional thermal management. Data Sheet 14 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.2 Internal Functional Description 4.2.1 VCC Pre-Charging and Typical VCC voltage profile During Start-up In ICL8201, a startup cell is not needed. As shown in Figure 4, once the mains input voltage is applied, a rectified voltage VBUS appears across the capacitor CIN. The pull up resistor RGD provides a current to charge the CGD capacitor and gradually generate one voltage level for the gate of external power MOSFET Q1. If voltage over CGD is high enough, VCC capacitor will be charged through external LED load, choke inductor LBUCK, external power MOSFET Q1, and diode DVCC. Because capacitor CGD is quite small (around 10nF), so charging this capacitor and consequently charging VCC capacitor CVCC will be within very short time. There is one zener diode, DZGD which is used to clamp voltage over CGD and its breakdown voltage can be 12V, so during startup, VCC voltage will be charged up to 12V - Vthreshold - VF (where Vthreshold is threshold voltage of power MOSFET Q1 and VF is forward voltage of DVCC). When VCC voltage reach UVLO turn-on threshold (which is 7.5V), the whole chip will be turned on and system will enter into normal operation after soft start. During normal operation, VCC capacitor will be charged through bypass capacitor CDS and power MOSFET (when VCC is lower than 12V - Vthreshold - VF). Figure 4 VCC voltage at start up When the VCC voltage exceeds the VCC turned-on threshold VVCC.ON at time t1, the IC begins to operate with softstart. VCC capacitor will be charged through bypass capacitor CDS, as shown in Figure 6. After some time, when VCC voltage is high enough, it will be clamped by the external Zener diode DZGD. Data Sheet 15 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description Figure 5 Charging current to VCC capacitor during normal operation 4.2.2 Soft Start Figure 6 Soft-Start profile Data Sheet 16 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description As shown in Figure 7, at time ton, the IC begins to operate with a soft-start. By using this soft-start, the switching stresses for the switch, diode and choke inductor are minimized. The Soft-Start implemented in ICL8201 is a digital time-based function. The preset soft-start time is tSS (24ms) with 4 steps. If not limited by other functions, the peak voltage on Vcs pin will increase step by step from 0.1V to 0.4V finally. After soft start, the peak VCS is limited by 0.9V current limitation. 4.2.3 Normal Regulation Operation Figure 7 Normal regulation operation of ICL8201 4.2.4 Zero Current Detection In the ICL8201 system, when power MOSFET is being turned on, current through choke inductor LBUCK will linearly ramp up, when power MOSFET is being turned off, current through choke inductor will linearly ramp down until 0A. Later when current through choke inductor reaches 0A, system will start to oscillate. In order to turn on power MOSFET when current through choke inductor reduce to 0A, it is necessary to do zero current detection for system. As shown in Figure 9, zero current detection is achieved by the following circuit. Data Sheet 17 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description Figure 8 Zero current detection circuit implemented in ICL8201 The above block diagram shown in Figure 9, where capacitor CDS is used to couple the high frequency signal to IC Drain and internally IC will accept the oscillation signal and do zero current detection. Internally, capacitor C1 will be used to further couple oscillation signal at DRAIN pin into low voltage signal; current source I1 and operational amplifier is used to ensure the maximum Vcross voltage to be 1.4V when there is no oscillation at the Drain pin; diode D1 is used to clamp point Vcross voltage not lower than -0.7V when power MOSFET is being turned on; when there is some high frequency signal transferred to point Vcross, the Vcross will be pulled down, and there is one comparator which is used to detect if Vcross is lower than 1.0V. When Vcross is lower than 1.0V, zero current point is detected. The typical DRAIN voltage Slew Rate necessary for zero current detection is 50V/µs for a delta VDRAIN of 0.5V and 2.5V/µs for a delta VDRAIN of 0.8V. As shown in Figure 10, upper side power MOSFET drain voltage and lower side power MOSFET drain & current through choke inductor with zero current detection used. Data Sheet 18 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description Time Figure 9 Waveform to show how is the drain voltage and current through choke inductor behave when zero current detection used 4.2.5 Peak Detection In order to do output current measurement and regulation, it is necessary to do VCS voltage peak detection. As shown in Figure 11, the peak voltage value of VCS is sample and hold for output current regulation purpose. Figure 10 Data Sheet Waveform to show peak detection of VCS signal 19 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.2.6 Voltage to Current Converter Figure 11 Block diagram to show peak detection & Voltage to Current block with current mirror circuit diagram From the above block diagram, at first VCS peak voltage is sample and hold, which will be applied to one Voltage to Current converter block, this voltage to Current converter block includes OPAMP A3, NMOS transistor N4 and resistor R2. The current ICSpeak will be equal to VCSpeak / R2. This ICSpeak will be mirrored by P2 and P3 into 7-times current source to charge external capacitor CON. Also there is one resistor R3 which is connected from Con to GND. The external CON works together with this internal resistor R3 establish the Con voltage which will be applied to the internal coarse and fine tuning block to determine the ON time, TON. 4.2.7 ON time generation ICL8201 uses constant on time control method, it can accept universal input voltage with wide output voltage range. The On time range is between 0.8µs and 20µs. The On Time is preset to 800ns during start up. The percentage of On time change is dependent on VCon voltage. VCon voltage is sensed every 12ms typically. The percentage of On time change with respect to VCon voltage is shown in Table 2. Table 6 Tuning mechanism used in ICL8201 VCon voltage VCon>1.8V 1.8V>VCon>1.6V 1.6V>VCon>1.5V 1.4V<VCon <1.5V 1.2V<VCon<1.4V VCon<1.2V Data Sheet On time Decrease by 50% Decrease by 10% Decrease by 0.2% Increase by 0.2% Increase by 10% Increase by 50% 20 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.2.8 How to calculate output average current The average of the VCS peak voltage divided by external sense resistor RCS will be the 2 times of the average current through choke inductor. Output average current only depends on sense resistor value, in order to get target output average current, equation 5.1 can be followed . . ×( ) (5.1) Where Rcs is sense resistor value and 3.5 is Peak VCS amplifier gain, 1.5V is CON threshold voltage. 4.2.9 Leading Edge Blanking Figure 12 Leading Edge Blanking Whenever the power MOSFET is switched on, a leading edge spike is generated due to parasitic capacitances. This spike can cause the gate drive to switch off unintentionally. In order to avoid a premature termination of the switching pulse, this spike is blanked out with a time constant of tLEB=205ns. 4.2.10 Driver Stage Cascode topology is adopted in ICL8201 system, one fixed voltage (for example: 12V) is applied to the Gate of the upper side power MOSFET, then if lower side power MOSFET is turned on, the whole current path will be turned on; if lower side power MOSFET is turned off, the whole current path will also be turned off. Data Sheet 21 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3 System Functional description 4.3.1 Start-Up behaviour 4.3.1.1 Start-Up: Into Normal Operation Start-up is executed in 3 phases: UVLO, power-up and soft start, as shown in figure 14. When the bus voltage is applied, the VCC capacitor CVCC is charged up until VCC reaches the VCC ‘ON’ threshold of VCC.ON = 7.5 V. After exceeding this threshold, the IC powers up into the soft start. VCON is charged up, the internal MOSFET starts switching. There is one fast charge function which is used to charge Con pin quickly to 1.5V after IC start to work. Start UP Curves: Vcc / Vcon / Iout 11 10 9 8 Voltage [V] 7 Vcc 6 Vcon Iout 5 Vccoff Vccon 4 3 2 1 0 Figure 13 Data Sheet Time Start Up 22 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.1.2 Start-Up: Soft-Start Phase During the digital Soft-Start phase, the current sensing voltage VCS is limited from 0.1 V up to 0.4 V. After the soft start phase (24 ms), the peak current sensing voltage threshold is set to VCS = 0.9 V for current limitation. Two additional thresholds are set in order to detect output short and short winding conditions. The first set to be VCSthShort = 0.6 V with no zero current detection as protection against short OUTPUT and second set to be VCSthShort = 1.2 V when a short winding at the BUCK choke, LBUCK, happens. In figure 15, shows the voltage behavior during start-up into normal operation. Start UP into Normal Operation 1.7 1.6 1.5 Current Sense Voltage Vcs [V] 1.4 1.3 VcsthShort = 1.2V: Short Winding Threshold 1.2 1.1 1 Vcsth = 0.9V: Cycle by Cycle Power Limiting Soft Start in 4 Steps 0.9 0.8 0.7 VcsthShort = 0.6V: Short OUT Threshold 0.6 0.5 0.4 0.3 0.2 VcsthFLP = 0.1V: Floating Load Threshold 0.1 0 0 3 6 9 12 15 18 21 24 27 30 33 36 Time [ms] VCSth [V] Figure 14 Data Sheet VCS [V] VCSthShort [V] VCSthFLP [V] Soft-Start 23 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.1.3 Start-Up: Short Output During the digital Soft-Start phase, a short output is detected when the current sensing voltage VCS exceeds the VCSthShort = 0.6 V threshold and the internal zero current detection signal is missing. The controller stops working after a consecutive 126 switching cycles and enters into the LATCH OFF mode. Short Output during Start UP 1.2 1.1 Current Sense Voltage Vcs [V] 1 Shut OFF into Latch Mode after 126 Cycles when: 0.9 0.8 VcsthShort = 0.6V: Short OUT Threshold 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 3 6 9 12 15 18 21 24 27 30 33 36 Time [ms] Vcsth Figure 15 Data Sheet Vcs VcsthShort Short Output 24 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.1.4 Start-Up: Floating Load Protection There is no effective floating load protection available. The risks during open or floating load are that the output voltage will be charged to the same voltage as input. If output capacitor, COUT, is not selected above the rated input voltage, it is recommended to include an output clamp circuit to prevent output capacitor, COUT, from operating above its rated voltage during open or floating load conditions. An open output (floating load) is detected when the current sensing voltage VCS stays below VCSthFLP = 0.12 V for 24 ms (soft start time) + 160 ms. After this blanking time, the controller stops working and enters into the LATCH OFF mode. Floating Load Protection (FLP) during Start UP 1.2 1.1 Current Sense Voltage Vcs [V] 1 0.9 0.8 0.7 0.6 0.5 Shut OFF into Latch Mode after first 24 ms +160ms 0.4 0.3 first 24 ms Blanking Time 0.2 VcsthFLP = 0.1V: Floating Load Threshold 0.1 0 0 3 6 9 12 15 18 21 24 27 30 33 36 Time [ms] Vcsth Figure 16 Data Sheet Vcs VcsFLP Floating Load Protection 25 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.1.5 Start-Up and Run Mode: Short Winding Protection A short winding (short on LBUCK) is detected when the current sensing voltage VCS exceeds the VCSthShort = 1.2 V threshold with a blanking time of 100ns and triggered after LEB signal with 3 continuous switching cycles. The controller stops working and enters into the LATCH OFF mode. Short WINDING Protection 2 1.9 1.8 1.7 Shut OFF into Latch Mode after 100ns when: 3 continuous pulses detected after LEB, VCS is still higher than 1.2V Current Sense Voltage Vcs [V] 1.6 1.5 1.4 1.3 VcsthShort = 1.2V: Short Winding Threshold 1.2 1.1 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 3 6 9 12 15 18 21 24 27 30 33 36 Time [ms] Vcsth Figure 17 Data Sheet Vcs VCSthShort [V] Short Winding Protection 26 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.2 Run Mode behaviour 4.3.2.1 Typical Curves during RUN Mode The chart below shows the typical curves of a BUCK converter: The black signal is the drain-to-source voltage of the MOSFET The blue signal is the MOSFET current during ON time The red signal shows the inductor current through the BUCK choke The red signal is the voltage at the BUCK choke Purple is the current through the free-wheeling diode when the MOSFET is turned OFF BLM Floating BUCK: Typical Curves in DCM Drain Source Voltage of Power MOS Q1 0V Propagation Delay Time Transistor Current 0A Inductor Current 0A Inductor Voltage 0V Diode Current 0V Time VDS Figure 18 Data Sheet ITransistor ILBuck VLBuck IDiode Typical Curves for Floating BUCK Topology 27 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.2.2 Run Mode: Short Output During normal operation (RUN mode), a short output is detected when the current sensing voltage VCS exceeds the VCSthShort = 0.6 V threshold and the internal zero current detection signal is missing. The controller stops working after 126 switching cycles and enters into the LATCH OFF mode. Short Output / Over Current Protection in RUN Mode 1.2 1.1 Current Sense Voltage Vcs [V] 1 Vcsth = 0.9V: Cycle by Cycle Power Limiting 0.9 Shut OFF into Latch Mode after 126 Cycles when: 0.8 VcsthShort = 0.6V: Short OUT Threshold 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 3 6 9 12 15 18 21 24 27 30 33 36 Time [ms] Vcsth Figure 19 Data Sheet Vcs VcsthShort Short Output During Run Mode 28 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.2.3 Run Mode: Floating Load Protection There is no effective floating load protection available. The risks during open or floating load are that the output voltage will be charged to the same voltage as input. If output capacitor, COUT, is not selected above the rated input voltage, it is recommended to include an output clamp circuit to prevent output capacitor, COUT, from operating above its rated voltage during open or floating load conditions. An open output (floating load) is detected when the current sensing voltage VCS stays below the VCSthFLP = 0.12 V threshold. The controller stops working after 160 ms blanking time and enters into the LATCH OFF mode. Floating Load Protection in Normal Mode Condition 1.2 1.1 1 Current Sense Voltage Vcs [V] 0.9 0.8 0.7 0.6 0.5 Shut OFF into Latch Mode after 160ms when 0.4 0.3 160ms Blanking Time 0.2 VcsthFLP = 0.1V: Floating Load Threshold 0.1 0 0 50 100 150 200 250 300 350 400 Time [ms] Vcsth Figure 20 Data Sheet Vcs VcsFLP Floating Load Protection in Run Mode 29 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.3 Intelligent Over-Temperature Protection (iOTP) The chart below shows the digital integrated intelligent over-temperature protection. In the event of overheating of the IC (Tj > 150 °C), the integrated thermal sensing on the IC reduces the output current (black signal) in 7 digital steps down to 50% of the target value of IOUT. This thermal downgrading is independent of time. When the temperature decreases, the IC returns in reverse into the value which is allowed, or back to the target value of IOUT. If the temperature continues to increase and exceeds Tj > 160 °C, the IC will enter LATCH OFF mode. Over Temperature Protection ICL8201 110 100 90 Output LED Current [%] 80 70 60 50 Digital Steps 40 30 20 10 0 138 140 142 144 146 148 150 152 154 156 158 160 162 164 166 168 170 Junction Temperature [°C] Figure 21 Data Sheet Intelligent Over-Temperature Protection iOTP 30 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.4 IC Working and Typical BUCK Curves 4.3.4.1 Critical Conduction operation with Constant TON Time and variable Frequency The chart below shows the working behavior over one AC half-cycle in critical conduction operation with constant tON time (see Gate Voltage) with variable frequency. The red signal shows the primary current through the MOSFET during ON time. The secondary (free-wheeling diode) current is shown in black. Ton Curves 3 2 1 Gate Signal Ipripk 0 Isec 0 20 40 60 80 100 120 140 160 180 ILBuck Vacin Iout -1 -2 -3 Figure 22 Data Sheet Time TON Characteristics 31 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Functional Description 4.3.4.2 Typical Curves of a BUCK Converter BLM Floating BUCK: Typical Curves in DCM Drain Source Voltage of Power MOS Q1 0V Propagation Delay Time Transistor Current 0A Inductor Current 0A Inductor Voltage 0V Diode Current 0V Time VDS Figure 23 Data Sheet ITransistor ILBuck VLBuck IDiode Typical Curves of a Floating BUCK converter 32 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Absolute Maximum Ratings and thermal Characteristics 5 Absolute Maximum Ratings and thermal Characteristics 5.1 Absolute Maximum Ratings Absolute maximum ratings are defined as ratings, which when exceeded may lead to destruction of the Integrated Circuit. For the same reason make sure that any capacitor connected to pin 3 (VCC) is discharged before assembling the application circuit. Table 7 Absolute Maximum Ratings Values Parameter Symbol Min. Typ. Max. Notes/Test Conditions Units Supply voltage VCC -0.3 - 18 V - Con VCon -0.3 - 3.3 V - VCS VCS -0.3 - 3.3 V - VDRAIN -0.3 - 27 V - IDRAINPeak - - 2.65 A For DC Input less than 31% Duty Cycle IDRAIN - - 400 mA RCS 0.34 - - Ω VESD_HBM - - 2 kV DRAIN Maximum Peak Drain current Maximum DC Drain current CS Shunt Resistor ESD capability at all pins HBM according to. JESD22-A114 Attention: Stresses above the maximum values listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Maximum ratings are absolute ratings; exceeding only one of these values may cause irreversible damage to the integrated circuit. Data Sheet 33 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Absolute Maximum Ratings and thermal Characteristics 5.2 Thermal Characteristics Table 8 Maximum Thermal Resistance Values Parameter Symbol Min. Typ. Max. Units Junction temperature range Tj -25 - 150 o Storage temperature range TSTG -65 - 150 o Total power dissipation Ptot - - 0.12 W Rthja - 264 - K/W 1 Junction-ambient point Notes/Test Conditions C C Based on footprint only at 105 °C ambient temperature. 1 For calculation of RthJS, please refer to application note AN077 (Thermal Resistance Calculation) The major part of the IC power dissipation is caused by the switch resistance in the conductive state. Therefore Equation 6.1 is an initial estimation used to calculate the power dissipation of the IC: = Data Sheet × (6.1) 34 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Electrical Characteristics 6 Electrical Characteristics All voltages without the high-side signals are measured in reference to ground (pin 2 & 5). The voltage levels are valid if other ratings are not violated. 6.1 DC Characteristics All parameters at Tamb = +25 °C, unless otherwise specified. Table 9 DC Characteristics Values Parameter Symbol Notes/Test Conditions Units Min. Typ. Max. VCC VCC.OFF - 18 V - VCC.OFF 5.7 6.0 6.5 V IC deactivated VCC.ON 7.2 7.5 8.0 V IC operating Supply current consumption open load ICC.open.load 0.60 0.82 1.10 mA ILED=0 mA Supply current consumption during latch ICC.latch 0.10 0.14 0.21 mA VCC=5.5V, VCS=0.85V Short winding current protection VCS threshold VCS.OCP 1.16 1.20 1.27 V Output load short protection VCS threshold VCS.OLP 0.58 0.62 0.66 V Output load short protection blanking time tout.SO - 126 - Switching cycle Output floating load protection VCS threshold voltage VCS.FLP 0.08 0.12 0.17 V Output floating load protection blanking time Tout.FLP - 160 - ms Peak VCS limitation voltage threshold VCSpeak 0.84 0.90 0.96 V Soft thermal protection temperature threshold TOTP.start 140 150 160 °C Junction temperature Soft thermal protection temperature range TOTP.range - 10 - °C Junction temperature Hard thermal protection temperature threshold TOTP.off 150 160 170 °C Junction temperature Peak VCS amplifier gain G - 3.5 - V/V VCon.TH 1.47 1.50 1.53 V Operating supply voltage 1 Under-Voltage Lock-Out Con threshold voltage Data Sheet 35 No zero current crossing is detected Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Electrical Characteristics 1 IC is deactivated once the supply voltage drops below VCC.OFF and becomes operative once the supply voltage rises above VCC.ON 6.2 Switching Characteristics All parameters at Tamb = +25 °C, unless otherwise specified. Table 10 Switching Characteristics Parameter Symbol Values Min. Typ. Max. Unit Test Condition Switching frequency fswitch 40 - 150 kHz Minimum On time tonmin - - 800 ns Maximum On time tonmax 20 - - µs Maximum Off time toffmax 30 40 - µs Leading Edge Blanking Time tLEB 110 205 300 ns Preset Soft-Start time tSS 17 24 31 ms LED Output current drift over supply voltage Iout.Vs - ±5 - % LED Output current drift over temperature Iout.Ts - ±5 - % For ambient temperature -25°C to +85°C LED Output current drift over load Iout.load - ±5 - % VOUT = 20V up to 60% VIN Switch on resistance RON.25°C - 370 470 mΩ ISWpeak=0.5 A, TJ=+25°C Switch on resistance RON.150°C - 530 610 mΩ ISWpeak=0.5 A, TJ=+150°C Data Sheet 36 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Application Example 7 Application Example Figure 24 Application Circuit for a 10W LED Lamp Data Sheet 37 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Bill of Materials 8 Bill of Materials ICL8201 BOM : Floating BUCK Single Choke Design: Demonstrator Input Voltage: VACIN = LED Voltage: VLED = LED Current: ILED = Nr. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Figure 25 Data Sheet QR Floating BUCK using ICL8201 110 - 275 VACIN 24 VOUT 350 mA Component Value Package FUSE OnBoard 175V / Varistor EPCOS S10K275 IC ICL8201 PG-SOT23-6-1 500V Q DSO CoolMOS BR DBL106 SMD DFREE MURS160 SMB DZGD BZX84C20 MiniMelf DVCC LL4148 MiniMelf D1 LL4148 MiniMelf CXCap 47nF / 275V~X RM5 33nF / CIN RM5 400VAC CVCC 10µF / 35V 1206 Ceramic CGD 100nF / 50V 1206 Ceramic CDS 120pF / 400V 1206 Ceramic CON 2.2µF / 50V 1206 Ceramic COUT 10µF LFilterCM 2X45mH/0.3A Wurth: 750311650 Single Choke Buck LBUCK 470µH Inductor RGD 1.0MΩ RM10 RSENSE 0.5Ω 1206 Bill of Materials(BOM) 38 Revision V2.0, 2015-05-25 ICL8201 AC/DC Buck Controller with PFC for LED Lamps Package Outline 9 Package Outline Figure 26 Package Outline (dimensions in mm) Data Sheet 39 Revision V2.0, 2015-05-25 w w w . i n f i n e o n . c o m Published by Infineon Technologies AG