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Quasi-Resonant PWM controller ICE2QS03G 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. FLEXGO™ of Microsoft Corporation. FlexRay™ is licensed by FlexRay Consortium. HYPERTERMINAL™ of Hilgraeve Incorporated. IEC™ of Commission Electrotechnique Internationale. IrDA™ of Infrared Data Association Corporation. ISO™ of INTERNATIONAL ORGANIZATION FOR STANDARDIZATION. MATLAB™ of MathWorks, Inc. MAXIM™ of Maxim Integrated Products, Inc. MICROTEC™, NUCLEUS™ of Mentor Graphics Corporation. MIPI™ of MIPI Alliance, Inc. MIPS™ of MIPS Technologies, Inc., USA. muRata™ of MURATA MANUFACTURING CO., MICROWAVE OFFICE™ (MWO) of Applied Wave Research Inc., OmniVision™ of OmniVision Technologies, Inc. Openwave™ Openwave Systems Inc. RED HAT™ Red Hat, Inc. RFMD™ RF Micro Devices, Inc. SIRIUS™ of Sirius Satellite Radio Inc. SOLARIS™ of Sun Microsystems, Inc. SPANSION™ of Spansion LLC Ltd. Symbian™ of Symbian Software Limited. TAIYO YUDEN™ of Taiyo Yuden Co. TEAKLITE™ of CEVA, Inc. TEKTRONIX™ of Tektronix Inc. TOKO™ of TOKO KABUSHIKI KAISHA TA. UNIX™ of X/Open Company Limited. 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 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Revision History Major changes since previous revision Date Version 2014-03-06 2.3 Changed By Change Description Added VVCCPD, and marking drawing. Removed VOUT. Revised typo, IVCCcharge1, IVCCcharge2, IZCMAX, outline dimension drawing and upgrade to -40°C operating temperature 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 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Table of Contents Revision History ...................................................................................................................................................4 Table of Contents .................................................................................................................................................5 1 1.1 1.2 Pin Configuration and Functionality ..............................................................................................7 Pin Configuration with PG-DSO-8......................................................................................................7 Pin Functionality.................................................................................................................................7 2 Representative Block Diagram .......................................................................................................8 3 3.1 3.2 3.3 3.3.1 3.3.1.1 3.3.1.2 3.3.2 3.3.2.1 3.3.3 3.3.4 3.4 3.4.1 3.5 3.5.1 3.5.2 3.5.3 3.6 Functional Description ....................................................................................................................9 VCC Pre-Charging and Typical VCC Voltage During Start-up...........................................................9 Soft-start ............................................................................................................................................9 Normal Operation.............................................................................................................................10 Digital Frequency Reduction.......................................................................................................10 Up/down counter....................................................................................................................10 Zero crossing (ZC counter) ....................................................................................................11 Ringing suppression time............................................................................................................12 Switch on determination ........................................................................................................12 Switch Off Determination ............................................................................................................12 Modulated gate drive ..................................................................................................................12 Current Limitation.............................................................................................................................13 Foldback Point Correction...........................................................................................................13 Active Burst Mode Operation ...........................................................................................................14 Entering Active Burst Mode Operation........................................................................................14 During Active Burst Mode Operation ..........................................................................................14 Leaving Active Burst Mode Operation ........................................................................................15 Protection Functions ........................................................................................................................16 4 4.1 4.2 4.3 4.3.1 4.3.2 4.3.3 4.3.4 4.3.5 4.3.6 4.3.7 4.3.8 4.3.9 4.3.10 Electrical Characteristics ..............................................................................................................17 Absolute Maximum Ratings .............................................................................................................17 Operating Range..............................................................................................................................17 Characteristics .................................................................................................................................18 Supply Section ............................................................................................................................18 Internal Voltage Reference .........................................................................................................18 PWM Section ..............................................................................................................................19 Current Sense.............................................................................................................................19 Soft Start.....................................................................................................................................19 Foldback Point Correction...........................................................................................................19 Digital Zero Crossing ..................................................................................................................20 Active Burst Mode.......................................................................................................................20 Protection....................................................................................................................................21 Gate Drive...................................................................................................................................21 5 Outline Dimension .........................................................................................................................22 6 Marking ...........................................................................................................................................23 Data Sheet 5 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Off-Line SMPS Quasi-Resonant PWM Controller with integrated 500V startup cell in DSO8 Product Highlights Active burst mode for low standby power Quasi resonant operation Digital frequency reduction for better overall system efficiency Integrated 500V startup cell Pb-free lead plating, halogen free mold compound, RoHS compliant PG-DSO-8 Features • • • • • • • • Quasi resonant operation till very low load Active burst mode operation at light/no load for low standby input power (< 100mW) Digital frequency reduction with decreasing load Startup cell for VCC pre-charging with constant current Built-in digital soft-start Foldback correction and cycle-by-cycle peak current limitation Auto restart mode for VCC Over-voltage protection, VCC Under-voltage protection and open loop/over-load protection Latch-off mode for adjustable output over-voltage protection and short-winding protection Description ICE2QS03G is a quasi-resonant PWM controller optimized for off-line switch power supply. The digital frequency reduction with decreasing load enables a quasi-resonant operation till very low load. As a result, the overall system efficiency is significantly improved compared to other conventional solutions. The active burst mode operation enables ultra-low power consumption at standby mode with small and controllable output voltage ripple. Based on the BiCMOS technology, the product has a wide operation range (up to 25V) of IC power supply and lower power consumption. The numerous protection functions give a full protection of the power supply system in failure situations. All of these make the ICE2QS03G an outstanding controller for quasiresonant flyback converter in the market. Applications Adapter/Charger, LCD monitor, DVD R/W, DVD Combo, Blue-ray/DVD player, Set-top box, Auxiliary power supply for CRT TV, LCD TV, PC, Server, Printer, TV, Home theater/Audio System, etc. Figure 1 Data Sheet Typical Application Type Package Marking ICE2QS03G PG-DSO-8 2QS03G 6 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Pin Configuration and Functionality 1 Pin Configuration and Functionality 1.1 Pin Configuration with PGDSO-8 Table 1 1.2 ZC (Zero Crossing) At this pin, the voltage from the auxiliary winding after a time delay circuit is applied. Internally, this pin is connected to the zero-crossing detector for switch-on determination. Additionally, the output overvoltage detection is realized by comparing the voltage Vzc with an internal preset threshold. Pin configuration Pin Symbol 1 ZC Zero Crossing 2 FB Feedback 3 CS Current Sense 4 GATE Gate Drive Output 5 HV High Voltage input 6 N.C. Not Connected 7 VCC Controller Supply Voltage 8 GND Controller Ground Pin Functionality Function FB (Feedback) Normally an external capacitor is connected to this pin for a smooth voltage VFB. Internally this pin is connected to the PWM signal generator block for switch-off determination (together with the current sensing signal), to the digital signal processing block for the frequency reduction with decreasing load during normal operation, and to the Active Burst Mode controller block for entering Active Burst Mode operation determination and burst ratio control during Active Burst Mode operation. Additionally, the open-loop / over-load protection is implemented by monitoring the voltage at this pin. CS (Current Sense) This pin is connected to the shunt resistor for the primary current sensing externally and to the PWM signal generator block for switch-off determination (together with the feedback voltage) internally. Moreover, short-winding protection is realized by monitoring the voltage Vcs during on-time of the main power switch. GATE (Gate Drive Output) This output signal drives the external main power switch, which is a power MOSFET in most case. Figure 2 HV (High Voltage) The pin HV is connected to the bus voltage externally and to the startup cell internally. The current through this pin pre-charges the VCC capacitor with constant current once the supply bus voltage is applied. Pin configuration PG-DSO-8 (top view) VCC (Power supply) VCC pin is the positive supply of the IC. The operating range is between VVCCoff and VVCCOVP. GND (Ground) This is the common ground of the controller. Data Sheet 7 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Representative Block Diagram 2 Representative Block Diagram Figure 3 Representative Block Diagram Data Sheet 8 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description 3 Functional Description 3.1 VCC Pre-Charging and Typical VCC Voltage During Start-up In ICE2QS03G, a high voltage startup cell is integrated. As shown in Figure 3, the start cell consists of a high voltage device and a controller, whereby the high voltage device is controlled by the controller. The startup cell provides a pre-charging of the VCC capacitor till VCC voltage reaches the VCC turned-on threshold VVCCon and the IC begins to operate. Once the mains input voltage is applied, a rectified voltage shows across the capacitor Cbus. The high voltage device provides a current to charge the VCC capacitor Cvcc. Before the VCC voltage reaches a certain value, the amplitude of the current through the high voltage device is only determined by its channel resistance and can be as high as several mA. After the VCC voltage is high enough, the controller controls the high voltage device so that a constant current around 1mA is provided to charge the VCC capacitor further, until the VCC voltage exceeds the turned-on threshold VVCCon. As shown as the time phase I in Figure 4, the VCC voltage increase near linearly and the charging speed is independent of the mains voltage level. Figure 4 VCC voltage at start up The time taking for the VCC pre-charging can then be approximately calculated as: where IVCCcharge2 is the charging current from the startup cell which is 1.05mA, typically. When the VCC voltage exceeds the VCC turned-on threshold VVCCon at time t1, the startup cell is switched off and the IC begins to operate with soft-start. Due to power consumption of the IC and the fact that there is still no energy from the auxiliary winding to charge the VCC capacitor before the output voltage is built up, the VCC voltage drops (Phase II). Once the output voltage is high enough, the VCC capacitor receives the energy from the auxiliary winding from the time point t2 onward. The VCC then will reach a constant value depending on output load. 3.2 Soft-start As shown in Figure 5, at the time ton, the IC begins to operate with a soft-start. By this soft-start the switching stresses for the switch, diode and transformer are minimized. The soft-start implemented in ICE2QS03G is a digital time-based function. The preset soft-start time is tSS (12ms) with 4 steps. If not limited by other functions, the peak voltage on CS pin will increase step by step from 0.32V to 1V finally. Data Sheet 9 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description Vcs_sst (V) 1.00 0.83 0.66 0.49 0.32 ton 3 6 9 Figure 5 Maximum current sense voltage during soft start 3.3 Normal Operation 12 Time(ms) The PWM controller during normal operation consists of a digital signal processing circuit including an up/down counter, a zero-crossing counter (ZC counter) and a comparator, and an analog circuit including a current measurement unit and a comparator. The switch-on and -off time points are each determined by the digital circuit and the analog circuit, respectively. As input information for the switch-on determination, the zerocrossing input signal and the value of the up/down counter are needed, while the feedback signal V FB and the current sensing signal VCS are necessary for the switch-off determination. Details about the full operation of the PWM controller in normal operation are illustrated in the following paragraphs. 3.3.1 Digital Frequency Reduction As mentioned above, the digital signal processing circuit consists of an up/down counter, a ZC counter and a comparator. These three parts are key to implement digital frequency reduction with decreasing load. In addition, a ringing suppression time controller is implemented to avoid mis-triggering by the high frequency oscillation, when the output voltage is very low under conditions such as soft start period or output short circuit. Functionality of these parts is described as in the following. 3.3.1.1 Up/down counter The up/down counter stores the number of the zero crossing where the main power switch is switched on after demagnetization of the transformer. This value is fixed according to the feedback voltage, V FB, which contains information about the output power. Indeed, in a typical peak current mode control, a high output power results in a high feedback voltage, and a low output power leads to a low regulation voltage. Hence, according to V FB, the value in the up/down counter is changed to vary the power MOSFET off-time according to the output power. In the following, the variation of the up/down counter value according to the feedback voltage is explained. The feedback voltage VFB is internally compared with three threshold voltages VFBZL, VFBZH and VFBR1, at each clock period of 48ms. The up/down counter counts then upward, keep unchanged or count downward, as shown in Table 2. Table 2 Operation of the up/down counter VFB up/down counter action Always lower than VFBZL Count upwards till 7 Once higher than VFBZL, but always lower than VFBZH Stop counting, no value changing Once higher than VFBZH, but always lower than VFBR1 Count downwards till 1 Once higher than VFBR1 Set up/down counter to 1 Data Sheet 10 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description In the ICE2QS03G, the number of zero crossing is limited to 7. Therefore, the counter varies between 1 and 7, and any attempt beyond this range is ignored. When VFB exceeds VFBR1 voltage, the up/down counter is reset to 1, in order to allow the system to react rapidly to a sudden load increase. The up/down counter value is also reset to 1 at the start-up time, to ensure an efficient maximum load start up. Figure 6 shows some examples on how up/down counter is changed according to the feedback voltage over time. The use of two different thresholds VFBZL and VFBZH to count upward or downward is to prevent frequency jittering when the feedback voltage is close to the threshold point. However, for a stable operation, these two thresholds must not be affected by the foldback current limitation (see section 3.4.1), which limits the V CS voltage. Hence, to prevent such situation, the threshold voltages, VFBZL and VFBZH, are changed internally depending on the line voltage levels. Figure 6 Up/down counter operation 3.3.1.2 Zero crossing (ZC counter) In the system, the voltage from the auxiliary winding is applied to the zero-crossing pin through a RC network, which provides a time delay to the voltage from the auxiliary winding. Internally this pin is connected to a clamping network, a zero-crossing detector, an output overvoltage detector and a ringing suppression time controller. During on-state of the power switch a negative voltage applies to the ZC pin. Through the internal clamping network, the voltage at the pin is clamped to certain level. The ZC counter has a minimum value of 0 and maximum value of 7. After the internal MOSFET is turned off, every time when the falling voltage ramp of on ZC pin crosses the VZCCT (100mV) threshold, a zero crossing is detected and ZC counter will increase by 1. It is reset every time after the DRIVER output is changed to high. The voltage VZC is also used for the output overvoltage protection. Once the voltage at this pin is higher than the threshold VZCOVP during off-time of the main switch, the IC is latched off after a fixed blanking time. To achieve the switch-on at voltage valley, the voltage from the auxiliary winding is fed to a time delay network (the RC network consists of Dzc, Rzc1, Rzc2 and Czc as shown in Figure 1) before it is applied to the zero-crossing detector through the ZC pin. The needed time delay to the main oscillation signal Δt should be approximately one fourth of the oscillation period, Tosc (by transformer primary inductor and drain-source capacitor) minus the propagation delay from the detected zero-crossing to the switch-on of the main switch tdelay. Data Sheet 11 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description This time delay should be matched by adjusting the time constant of the RC network which is calculated as: 3.3.2 Ringing suppression time After MOSFET is turned off, there will be some oscillation on VDS, which will also appear on the voltage on ZC pin. To avoid mis-triggering by such oscillations to turn on the MOSFET, a ringing suppression timer is implemented. This suppression time is depended on the voltage VZC. If the voltage VZC is lower than the threshold VZCRS, a longer preset time tZCRS2 is applied. However, if the voltage VZC is higher than the threshold, a shorter time tZCRS1 is set. 3.3.2.1 Switch on determination After the gate drive goes to low, it cannot be changed to high during ring suppression time. After ring suppression time, the gate drive can be turned on when the ZC counter value is higher or equal to up/down counter value. However, it is also possible that the oscillation between primary inductor and drain-source capacitor damps very fast and IC cannot detect enough zero crossings and ZC counter value will not be high enough to turn on the gate drive. In this case, a maximum off time is implemented. After gate drive has been remained off for the period of TOffMax, the gate drive will be turned on again regardless of the counter values and V ZC. This function can effectively prevent the switching frequency from going lower than 20kHz. Otherwise it will cause audible noise during start up. 3.3.3 Switch Off Determination In the converter system, the primary current is sensed by an external shunt resistor, which is connected between low-side terminal of the main power switch and the common ground. The sensed voltage across the shunt resistor VCS is applied to an internal current measurement unit, and its output voltage V1 is compared with the regulation voltage VFB. Once the voltage V1 exceeds the voltage VFB, the output flip-flop is reset. As a result, the main power switch is switched off. The relationship between the V1 and the VCS is described by: To avoid mis-triggering caused by the voltage spike across the shunt resistor at the turn on of the main power switch, a leading edge blanking time, tLEB, is applied to the output of the comparator. In other words, once the gate drive is turned on, the minimum on time of the gate drive is the leading edge blanking time. In addition, there is a maximum on time, tOnMax, limitation implemented in the IC. Once the gate drive has been in high state longer than the maximum on time, it will be turned off to prevent the switching frequency from going too low because of long on time. 3.3.4 Modulated gate drive The drive-stage is optimized for EMI consideration. The switch on speed is slowed down before it reaches the TM CoolMOS turn on threshold. That is a slope control of the rising edge at the output of driver (Figure 7). Thus the leading switch spike during turn on is minimized. Data Sheet 12 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description Figure 7 Gate rising waveform 3.4 Current Limitation There is a cycle by cycle current limitation realized by the current limit comparator to provide an over-current detection. The source current of the MOSFET is sensed via a sense resistor R CS. By means of RCS the source current is transformed to a sense voltage VCS which is fed into the pin CS. If the voltage VCS exceeds an internal voltage limit, adjusted according to the Mains voltage, the comparator immediately turns off the gate drive. To prevent the Current Limitation process from distortions caused by leading edge spikes, a Leading Edge Blanking time (tLEB) is integrated in the current sensing path. A further comparator is implemented to detect dangerous current levels (V CSSW) which could occur if one or more transformer windings are shorted or if the secondary diode is shorted. To avoid an accidental latch off, a spike blanking time of tCSSW is integrated in the output path of the comparator. 3.4.1 Foldback Point Correction When the main bus voltage increases, the switch on time becomes shorter and therefore the operating frequency is also increased. As a result, for a constant primary current limit, the maximum possible output power is increased which is beyond the converter design limit. To avoid such a situation, the internal foldback point correction circuit varies the V CS voltage limit according to the bus voltage. This means the VCS will be decreased when the bus voltage increases. To keep a constant maximum input power of the converter, the required maximum VCS versus various input bus voltage can be calculated, which is shown in Figure 8. Figure 8 Data Sheet Variation of the VCS limit voltage according to the IZC current 13 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description According to the typical application circuit, when MOSFET is turned on, a negative voltage proportional to bus voltage will be coupled to auxiliary winding. Inside ICE2QS03G, an internal circuit will clamp the voltage on ZC pin to nearly 0V. As a result, the current flowing out from ZC pin can be calculated as When this current is higher than IZC_FS, the amount of current exceeding this threshold is used to generate an offset to decrease the maximum limit on VCS. Since the ideal curve shown in Figure 8 is a nonlinear one, a digital block in ICE2QS03G is implemented to get a better control of maximum output power. Additional advantage to use digital circuit is the production tolerance is smaller compared to analog solutions. The typical maximum limit on VCS versus the ZC current is shown in Figure 9. Figure 9 VCS-max versus IZC 3.5 Active Burst Mode Operation At light load condition, the IC enters Active Burst Mode operation to minimize the power consumption. Details about Active Burst Mode operation are explained in the following paragraphs. 3.5.1 Entering Active Burst Mode Operation 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 0.17V; the up/down counter is NZC_ABM (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. 3.5.2 During Active Burst Mode Operation After entering the Active Burst Mode the feedback voltage rises as VOUT starts to decrease due to the inactive PWM section. One comparator observes the feedback signal if the voltage level V FBBOn (3.6V) is exceeded. In that case the internal circuit is again activated by the internal bias to start with switching. Data Sheet 14 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description Turn-on of the power MOSFET is triggered by the timer. The PWM generator for Active Burst Mode operation composes of a timer with a fixed frequency of fsB (52kHz, typical) and an analog comparator. Turn-off is resulted if the voltage across the shunt resistor at CS pin hits the threshold VcsB (0.34V). A turn-off can also be triggered if the duty ratio exceeds the maximal duty ratio DmaxB (50%). In operation, the output flip-flop will be reset by one of these signals which come first. If the output load is still low, the feedback signal decreases as the PWM section is operating. When feedback signal reaches the low threshold VFBBOff (3.0V), the internal bias is reset again and the PWM section is disabled until next time regulation signal increases beyond the VFBBOn (3.6V) threshold. If working in Active Burst Mode the feedback signal is changing like a saw tooth between VFBBOff and VFBBOn shown in Figure 10. 3.5.3 Leaving Active Burst Mode Operation The feedback voltage immediately increases if there is a high load jump. This is observed by a comparator. As the current limit is 34% during Active Burst Mode a certain load is needed so that feedback voltage can exceed VFBLB (4.5V). After leaving active burst 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. Figure 10 Data Sheet Signals in Active Burst Mode 15 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Functional Description 3.6 Protection Functions The IC provides full protection functions. The following table summarizes these protection functions. Table 3 Protection features VCC Over-voltage VCC Under-voltage Over-load/Open Loop Over-temperature Output Over-voltage Short Winding Auto Restart Mode Auto Restart Mode Auto Restart Mode Auto Restart Mode Latched Off Mode Latched Off Mode During operation, the VCC voltage is continuously monitored. In case of an under-voltage or an over-voltage, the IC is reset and the main power switch is then kept off. After the VCC voltage falls below the threshold VVCCoff, the startup cell is activated. The VCC capacitor is then charged up. Once the voltage exceeds the threshold VVCCon, the IC begins to operate with a new soft-start. In case of open control loop or output over load, the feedback voltage will be pulled up. After a blanking time of tOLP_B (30ms), the IC enters auto-restart mode. The blanking time here enables the converter to provide a peak power in case the increase in VFB is due to a sudden load increase. This output over load protection is disabled during burst mode. During off-time of the power switch, the voltage at the zero-crossing pin is monitored for output over-voltage detection. If the voltage is higher than the preset threshold VZCOVP, the IC is latched off after the preset blanking time tZCOVP. This latch off mode can only be reset if the Vcc < VVCCPD. If the junction temperature of IC controller exceeds TjCon (130 °C), the IC enters into OTP auto restart mode. This OTP is disabled during burst mode. If the voltage at the current sensing pin is higher than the preset threshold VCSSW during on-time of the power switch, the IC is latched off. This is short-winding protection. The short winding protection is disabled during burst mode. During latch-off protection mode, the VCC voltage drops to VVCCoff (10.5V) and then the startup cell is activated. The VCC voltage is then charged to VVCCon (18V). The startup cell is shut down again. This action repeats again and again. There is also a maximum on time limitation implemented inside the ICE2QS03G. Once the gate voltage is high and longer than tOnMax, the switch is turned off immediately. Data Sheet 16 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Electrical Characteristics 4 Electrical Characteristics Note : All voltages are measured with respect to ground (Pin 8). The voltage levels are valid if other ratings are not violated. 4.1 Absolute Maximum Ratings Note : Absolute maximum ratings are defined as ratings, which when being exceeded may lead to destruction of the integrated circuit. For the same reason it needs to make sure that any capacitor that will be connected to pin 7 (VCC) is discharged before assembling the application circuit. Parameter Limit Values Symbol min. HV Voltage VHV VCC Supply Voltage VVCC -0.3 27 V FB Voltage VFB -0.3 5.5 V ZC Voltage VZC -0.3 5.5 V CS Voltage VCS -0.3 5.5 V IZCMAX - 3 mA Junction Temperature Tj -40 150 °C Storage Temperature TS -55 150 °C Thermal Resistance Junction -Ambient RthJA - 185 K/W ESD Capability (incl. Drain Pin) VESD - 2 kV Current out from ZC pin 4.2 - Unit max. 500 Remarks V Human body 1 model Operating Range Note : Within the operating range the IC operates as described in the functional description. Parameter Symbol Limit Values min. max. Unit VCC Supply Voltage VVCC VVCCoff VVCCOVP V Junction Temperature of Controller TjCon -40 130 °C 1 Remarks Limited by over temperature protection According to EIA/JESD22-A114-B (discharging a 100pF capacitor through a 1.5kW series resistor) Data Sheet 17 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Electrical Characteristics 4.3 Characteristics 4.3.1 Supply Section Note : The electrical characteristics involve the spread of values within the specified supply voltage and junction temperature range Tj from – 40 °C to 125 °C. Typical values represent the median values, which are related to 25°C. If not otherwise stated, a supply voltage of VCC = 18 V is assumed. Parameter Symbol Limit Values Unit Test Condition min. typ. max. IVCCstart - 300 550 μA VVCC =VVCCon -0.2V IVCCcharge1 - 1.22 5.0 mA VVCC = 0V IVCCcharge2 0.8 1.1 - mA VVCC = 1V IVCCcharge3 - 1 - mA VVCC =VVCCon -0.2V IDrainIn - - 2 mA VVCC =VVCCon -0.2V Leakage Current of Startup Cell IDrainLeak - 0.2 50 μA VDrain = 500V at Tj=100°C Supply Current in normal operation IVCCNM - 1.5 2.3 mA IFB = 0A Supply Current in Auto Restart Mode with Inactive Gate IVCCAR - 300 - μA IFB = 0A Supply Current in Latch-off Mode IVCClatch - 300 - μA IFB = 0A Supply Current in Burst Mode with inactive Gate IVCCburst - 500 950 μA VFB = 2.5V, exclude the current flowing out from FB pin VCC Turn-On Threshold VVCCon 17.0 18.0 19.0 V VCC Turn-Off Threshold VVCCoff 9.8 10.5 11.2 V VCC Turn-On/Off Hysteresis VVCChys - 7.5 - V Start Up Current VCC Charge Current Maximum Input Current of Startup Cell 4.3.2 Internal Voltage Reference Parameter Internal Reference Voltage Data Sheet Symbol VREF Limit Values min. typ. max. 4.80 5.00 5.20 18 Unit V Test Condition Measured at pin FB IFB=0 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Electrical Characteristics 4.3.3 PWM Section Parameter Symbol Limit Values Unit min. typ. max. RFB 14 23 33 kΩ PWM-OP Gain GPWM 3.18 3.3 - - Offset for Voltage Ramp VPWM 0.6 0.7 - V Maximum on time in normal operation tOnMax 22 30 41 μs Feedback Pull-Up Resistor 4.3.4 Current Sense Parameter Symbol Limit Values min. typ. max. Unit Peak current limitation in normal operation VCSth 0.97 1.03 1.09 V Leading Edge Blanking time tLEB 200 330 460 ns Peak Current Limitation in Active Burst Mode VCSB 0.29 0.34 0.39 V 4.3.5 Test Condition Soft Start Parameter Soft-Start time Symbol Limit Values min. typ. max. 8.5 12 - tSS Unit soft-start time step - 3 - ms Internal regulation voltage at first step VSS1 1 - 1.76 - V Internal regulation voltage step at soft start VSS_S - 0.56 - V 4.3.6 1 Test Condition ms 1 tSS_S Foldback Point Correction Parameter Symbol ZC current first step threshold Limit Values Unit min. typ. max. IZC_FS 0.35 0.5 0.621 mA ZC current last step threshold IZC_LS 1.3 1.7 2.2 mA CS threshold minimum VCSMF - 0.66 - V 1 Test Condition Test Condition Izc=2.2mA, VFB=3.8V The parameter is not subjected to production test - verified by design/characterization Data Sheet 19 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Electrical Characteristics 4.3.7 Digital Zero Crossing Parameter Symbol Limit Values min. typ. max. Unit Test Condition Zero crossing threshold voltage VZCCT 50 100 170 mV Ringing suppression threshold VZCRS - 0.7 - V Minimum ringing suppression time tZCRS1 1.62 2.5 4.5 μs VZC > VZCRS Maximum ringing suppression time tZCRS2 - 25 - μs VZC < VZCRS Threshold to set Up/Down Counter to one VFBR1 - 3.9 - V Threshold for downward counting at low line VFBZHL - 3.2 - V Threshold for upward counting at low line VFBZLL - 2.5 - V Threshold for downward counting at high line VFBZHH - 2.9 - V Threshold for upward counting at high line VFBZLH - 2.3 - V ZC current for IC switch threshold to high line IZCSH - 1.3 - mA ZC current for IC switch threshold to low line IZCSL - 0.8 - mA tCOUNT - 48 - ms tOffMax 30 42 57.5 μs Counter time 1 Maximum restart time in normal operation 4.3.8 Active Burst Mode Parameter Symbol Limit Values Unit min. typ. max. VFBEB - 1.25 - NZC_ABM - 7 - tBEB - 24 - ms Feedback voltage for leaving Active Burst Mode VFBLB - 4.5 - V Feedback voltage for burst-on VFBBOn - 3.6 - V Feedback voltage for burst-off VFBBOff - 3.0 - V Feedback voltage for entering Active Burst Mode Minimum Up/down value for entering Active Burst Mode Blanking time for entering Active Burst Mode 1 Test Condition V The parameter is not subjected to production test - verified by design/characterization Data Sheet 20 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Electrical Characteristics Fixed Switching Frequency in Active Burst Mode Max. Duty Cycle in Active Burst Mode 4.3.9 fsB 39 52 65 DmaxB - 0.5 - kHz Protection Parameter Symbol VCC overvoltage threshold Limit Values Unit min. typ. max. VVCCOVP 24.0 25.0 26.0 V Over Load or Open Loop Detection threshold for OLP protection at FB pin VFBOLP - 4.5 - V Over Load or Open Loop Protection Blanking Time tOLP_B 20 30 44 ms Output Overvoltage detection threshold at the ZC pin VZCOVP 3.55 3.7 3.84 V Blanking time for Output Overvoltage protection tZCOVP - 100 - μs Threshold for short winding protection VCSSW 1.63 1.68 1.78 V Blanking time for short-winding protection tCSSW - 190 - ns TjCon 130 140 150 °C VVCCPD 5.2 - 7.8 V Over temperature protection 1 Power Down Reset threshold for Latched Mode Test Condition After Latched Off Mode is entered Note : The trend of all the voltage levels in the Control Unit is the same regarding the deviation except VVCCOVP & VVCCPD. 4.3.10 Gate Drive Parameter Symbol Limit Values min. typ. max. Unit Test Condition Output voltage at logic low VGATElow - - 1.0 V VVCC=18V IOUT = 10mA Output voltage at logic high VGATEhigh 9.0 10.0 - V VVCC=18V IOUT = -10mA Output voltage active shut down VGATEasd - - 1.0 V VVCC = 7V IOUT = 10mA Rise Time trise - 117 - ns COUT = 1.0nF VGATE= 2V ... 8V Fall Time tfall - 27 - ns COUT = 1.0nF VGATE= 8V ... 2V Data Sheet 21 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Outline Dimension 5 Outline Dimension Figure 11 PG-DSO-8 (Pb-free lead plating Plastic Dual Small Outline Package) Data Sheet 22 V2.3, 2014-03-06 Quasi-Resonant PWM controller ICE2QS03G Marking 6 Marking Figure 12 Marking for ICE2QS03G Data Sheet 23 V2.3, 2014-03-06 w w w . i n f i n e o n . c o m Published by Infineon Technologies AG