FSQ0365, FSQ0265, FSQ0165, FSQ321 Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter – Low EMI and High Efficiency Features Description Optimized for Valley Switching Converter (VSC) A Valley Switching Converter generally shows lower EMI and higher power conversion efficiency than a conventional hard-switched converter with a fixed switching frequency. The FSQ-series is an integrated Pulse-Width Modulation (PWM) controller and SenseFET specifically designed for valley switching operation with minimal external components. The PWM controller includes an integrated fixed-frequency oscillator, under-voltage lockout, Leading-Edge Blanking (LEB), optimized gate driver, internal soft-start, temperature-compensated precise current sources for loop compensation, and self-protection circuitry. Low EMI through Variable Frequency Control and Inherent Frequency Modulation High Efficiency through Minimum Voltage Switching Narrow Frequency Variation Range Over Wide Load and Input Voltage Variation Advanced Burst-Mode Operation for Low Standby Power Consumption Pulse-by-Pulse Current Limit Protection Functions: Overload Protection (OLP), Over-Voltage Protection (OVP), Abnormal OverCurrent Protection (AOCP), Internal Thermal Shutdown (TSD) Under-Voltage Lockout (UVLO) with Hysteresis Internal Startup Circuit Compared with discrete MOSFET and PWM controller solutions, the FSQ-series reduces total cost, component count, size and weight; while simultaneously increasing efficiency, productivity, and system reliability. This device provides a basic platform for cost-effective designs of valley switching fly-back converters. Related Application Notes AN-4137 - Design Guidelines for Offline Flyback Converters Using Fairchild Power Switch (FPS™) AN-4141 - Troubleshooting and Design Tips for Fairchild Power Switch (FPS™) Flyback Applications Power Supplies for DVP Player, DVD Recorder, AN-4147 - Design Guidelines for RCD Snubber of Flyback Converters Adapter AN-4150 - Design Guidelines for Flyback Converters Using FSQ-series Fairchild Power Switch (FPS™) AN-4134 - Design Guidelines for Off-line Forward Converters Using Fairchild Power Switch (FPS™) Internal High-Voltage SenseFET: 650V Built-in Soft-Start: 15ms Applications Set-Top Box Auxiliary Power Supply for PC, LCD TV, and PDP TV © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter August 2011 Maximum Output Table(1) Operating Current RDS(ON) 230VAC ±15%(2) 85-265VAC Part Number Package Temperature Limit (Max.) Open Open (3) Adapter(3) (4) Adapter (4) Frame Frame FSQ321 8-DIP FSQ321L 8-LSOP FSQ321LX 8-LSOP (Tape & Reel) FSQ0165RN 8-DIP FSQ0165RL 8-LSOP 8-LSOP FSQ0165RLX (Tape & Reel) FSQ0265RN 8-DIP FSQ0265RL 8-LSOP FSQ0365RN 8-DIP Replaces Devices -40 to +85°C 0.6A 19Ω 8W 12W 7W 10W FSDL321 FSDM311 -40 to +85°C 0.9A 10Ω 10W 15W 9W 13W FSDL0165RN -40 to +85°C 1.2A 6Ω 14W 20W 11W 16W FSDM0265RN FSDM0265RNB FSDM0365RN -40 to +85°C 1.5A 4.5Ω 17.5W 25W 13W 19W FSDM0365RNB FSQ0365RL 8-LSOP Notes: 1. The junction temperature can limit the maximum output power. 2. 230VAC or 100/115VAC with voltage doubler. The maximum power with CCM operation 3. Typical continuous power in a non-ventilated, enclosed adapter measured at 50C ambient temperature. 4. Maximum practical continuous power in an open-frame design at 50C ambient temperature. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 2 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Ordering Information Vo AC IN Vstr Drain PWM Sync Vfb GND Vcc Figure 1. Typical Flyback Application Internal Block Diagram Sync 4 Vstr Vcc 5 2 Drain 6 7 8 + OSC 0.7V/0.2V + + Vref VCC Idelay Vfb 3 0.35/0.55 VBurst Vref VCC Good - 8V/12V IFB PWM 3R R S SoftStart LEB 200ns Q Gate Driver R Q AOCP VSD Sync Vovp S TSD 6V 2.5 s Time Delay 1 Q VOCP (1.1V) GND R Q 6V VCC Good FSQ0365RN Rev.00 Figure 2. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 Internal Block Diagram www.fairchildsemi.com 3 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Application Circuit Figure 3. Pin Configuration (Top View) Pin Definitions Pin# Name 1 GND SenseFET source terminal on primary side and internal control ground. VCC Positive supply voltage input. Although connected to an auxiliary transformer winding, current is supplied from pin 5 (Vstr) via an internal switch during startup (see Figure 2). It is not until VCC reaches the UVLO upper threshold (12V) that the internal startup switch opens and device power is supplied via the auxiliary transformer winding. Vfb The feedback voltage pin is the non-inverting input to the PWM comparator. It has a 0.9mA current source connected internally while a capacitor and opto-coupler are typically connected externally. There is a time delay while charging external capacitor Cfb from 3V to 6V using an internal 5A current source. This delay prevents false triggering under transient conditions, but still allows the protection mechanism to operate under true overload conditions. 2 3 Description 4 Sync This pin is internally connected to the sync-detect comparator for valley switching. Typically the voltage of the auxiliary winding is used as Sync input voltage and external resistors and capacitor are needed to make delay to match valley point. The threshold of the internal sync comparator is 0.7V/0.2V. 5 Vstr This pin is connected to the rectified AC line voltage source. At startup, the internal switch supplies internal bias and charges an external storage capacitor placed between the Vcc pin and ground. Once the VCC reaches 12V, the internal switch is opened. 6, 7, 8 Drain The drain pins are designed to connect directly to the primary lead of the transformer and are capable of switching a maximum of 650V. Minimizing the length of the trace connecting these pins to the transformer decreases leakage inductance. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 4 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Pin Assignments Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. TA=25°C, unless otherwise specified. Symbol Parameter Min. Max. Unit VSTR Vstr Pin Voltage 500 V VDS Drain Pin Voltage 650 V VCC Supply Voltage VFB Feedback Voltage Range Sync Pin Voltage VSync IDM EAS Drain Current Pulsed(6) Single Pulsed Avalanche Energy(7) 20 V -0.3 9.0 V -0.3 9.0 V FSQ0365 12.0 FSQ0265 8.0 FSQ0165 4.0 FSQ321 1.5 FSQ0365 230 FSQ0265 140 FSQ0165 50 FSQ321 10 PD Total Power Dissipation TJ Recommended Operating Junction Temperature TA Operating Ambient Temperature Storage Temperature -55 TSTG ESD A mJ 1.5 W -40 Internally Limited C -40 +85 C +150 C Human Body Model; JESD22-A114 CLASS 1C Machine Model; JESD22-A115 CLASS B Notes: 5. Repetitive rating: Pulse width limited by maximum junction temperature. 6. L=51mH, starting TJ=25°C. Thermal Impedance Symbol Parameter Value Unit (7) 8-DIP θJA θJC Junction-to-Ambient Thermal Resistance(8) Junction-to-Case Thermal Resistance 80 (9) 20 θJT Junction-to-Top Thermal Resistance(10) Notes: 7. All items are tested with the standards JESD 51-2 and 51-10 (DIP). 8. Free-standing with no heat-sink, under natural convection. 9. Infinite cooling condition - refer to the SEMI G30-88. 10. Measured on the package top surface. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 °C/W 35 www.fairchildsemi.com 5 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Absolute Maximum Ratings T A=25C unless otherwise specified. Symbol Parameter Condition Min. Typ. Max. Unit SenseFET Section BVDSS Drain-Source Breakdown Voltage VCC=0V, ID=100µA IDSS Zero-Gate-Voltage Drain Current VDS=650V 650 100 3.5 4.5 5.0 6.0 8.0 10.0 FSQ321 14.0 19.0 FSQ0365 315 FSQ0365 RDS(ON) CISS COSS Drain-Source OnState Resistance(11) Input Capacitance Output Capacitance FSQ0265 FSQ0165 FSQ0265 FSQ0165 TJ=25C, ID=0.5A 550 VGS=0V, VDS=25V, f=1MHz FSQ321 162 FSQ0365 47 FSQ0265 FSQ0165 38 VGS=0V, VDS=25V, f=1MHz Reverse Transfer Capacitance 18 9.0 FSQ0265 17.0 VGS=0V, VDS=25V, f=1MHz tr td(off) tf Turn-On Delay Rise Time Turn-Off Delay Fall Time 3.8 FSQ0365 11.2 FSQ0265 20.0 FSQ0165 VDD=350V, ID=25mA 9.5 FSQ0365 34 FSQ0165 15 VDD=350V, ID=25mA 19 FSQ0365 28.2 FSQ0165 55.0 VDD=350V, ID=25mA 33.0 FSQ0365 32 FSQ0165 ns 30.0 FSQ321 FSQ0265 ns 4 FSQ321 FSQ0265 ns 12.0 FSQ321 FSQ0265 pF 10.0 FSQ321 td(on) pF 25 FSQ0365 FSQ0165 µA pF 250 FSQ321 CRSS V 25 VDD=350V, ID=25mA ns 10 FSQ321 42 Burst-Mode Section VBURH VBURL Burst-Mode Voltage TJ=25°C, tPD=200ns(12) VBUR(HYS) 0.45 0.55 0.65 0.25 0.35 0.45 200 V V mV Continued on the following page… © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 6 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Electrical Characteristics T A=25C unless otherwise specified. Symbol Parameter Conditions Min. Typ. Max. Unit All but T =25°C FSQ321 J 10.5 12.0 13.5 µs Control Section tON.MAX1 Maximum On Time1 tON.MAX2 Maximum On Time2 FSQ321 TJ=25°C 6.35 7.06 7.77 µs tB1 Blanking Time1 All but FSQ321 13.2 15.0 16.8 µs tB2 Blanking Time2 FSQ321 7.5 tW Detection Time Window (14) 8.2 µs TJ=25°C, Vsync=0V 3.0 µs ±5 ±10 % 700 900 1100 µA 0 % 11 12 13 V 7 8 9 V fS Switching Frequency Variation -25C < TJ < 85C IFB Feedback Source Current VFB=0V Minimum Duty Cycle VFB=0V DMIN VSTART VSTOP UVLO Threshold Voltage After Turn-on tS/S1 Internal Soft-Start Time 1 All but With Free-Running FSQ321 Frequency tS/S2 Internal Soft-Start Time 2 FSQ321 15 ms With Free-Running Frequency 10 ms Protection Section ILIM VSD IDELAY FSQ0365 TJ=25°C, di/dt=240mA/µs 1.32 1.50 1.68 FSQ0265 TJ=25°C, di/dt=200mA/µs 1.06 1.20 1.34 FSQ0165 TJ=25°C, di/dt=175mA/µs 0.8 0.9 1.0 FSQ321 TJ=25°C, di/dt=125mA/µs 0.53 0.60 0.67 Shutdown Feedback Voltage VCC=15V 5.5 6.0 6.5 V Shutdown Delay Current VFB=5V 4.0 5.0 6.0 µA Peak Current Limit tLEB Leading-Edge Blanking Time(13) VOVP Over-Voltage Protection tOVP Over-Voltage Protection Blanking Time TSD Thermal Shutdown Temperature(13) 200 VCC=15V, VFB=2V A ns 5.5 6.0 6.5 V 2 3 4 µs 125 140 155 °C Sync Section VSH VSL tSync Sync Threshold Voltage 0.55 0.70 0.85 V 0.14 0.20 0.26 V Sync Delay Time(13,14) 300 ns Total Device Section IOP ISTART ICH Operating Supply Current (Control Part Only) VCC=15V Start Current Startup Charging Current 1 3 5 mA VCC=VSTART - 0.1V (Before VCC Reaches VSTART) 270 360 450 µA VCC=0V, VSTR=Minimum 40V 0.65 0.85 1.00 mA VSTR Minimum VSTR Supply Voltage Notes: 11. Pulse test: Pulse-Width=300s, duty=2%. 12. Propagation delay in the control IC. 13. Though guaranteed, it is not 100% tested in production. 14. Includes gate turn-on time. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 26 V www.fairchildsemi.com 7 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Electrical Characteristics (Continued) Function FSDM0x65RNB FSQ-Series Operation Method Constant Frequency PWM Valley Switching Operation EMI Reduction Frequency Modulation Valley Switching & Inherent Frequency Modulation Advantages of FSQ-Series Improved efficiency by valley switching Reduced EMI noise Reduce EMI noise in two ways Improved standby power by valley switching also in Burst-Mode Operation Fixed Burst Peak Protection © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 burst-mode Advanced BurstMode Because the current peak during burst operation is AOCP Improved reliability through precise abnormal over- dependent on VFB, it is easier to solve audible noise current protection www.fairchildsemi.com 8 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Comparison Between FSDM0x65RNB and FSQ-Series 1.2 1.2 1.0 1.0 Normalized Normalized Characteristic graphs are normalized at TA=25°C. 0.8 0.6 0.4 0.2 0.0 -25 0.8 0.6 0.4 0.2 0 25 50 75 100 0.0 -25 125 0 Temperature [°C] Operating Supply Current (IOP) vs. TA Figure 5. 1.2 1.2 1.0 1.0 Normalized Normalized Figure 4. 0.8 0.6 0.4 0.2 0.0 -25 125 0.4 0.2 0 25 50 75 100 0.0 -25 125 0 25 50 75 100 125 Temperature [°C] UVLO Stop Threshold Voltage (VSTOP) vs. TA Figure 7. 1.0 1.0 Normalized Normalized 100 0.6 1.2 0.8 0.6 0.4 0.2 Startup Charging Current (ICH) vs. TA 0.8 0.6 0.4 0.2 0 25 50 75 100 0.0 -25 125 Temperature [°C] Figure 8. 75 0.8 1.2 0.0 -25 50 UVLO Start Threshold Voltage (VSTART) vs. TA Temperature [°C] Figure 6. 25 Temperature [°C] 25 50 75 100 125 Temperature [°C] Initial Switching Frequency (fS) vs. TA © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 0 Figure 9. Maximum On Time (tON.MAX) vs. TA www.fairchildsemi.com 9 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Typical Performance Characteristics 1.2 1.2 1.0 1.0 Normalized Normalized Characteristic graphs are normalized at TA=25°C. 0.8 0.6 0.4 0.2 0.0 -25 0.8 0.6 0.4 0.2 0 25 50 75 100 0.0 -25 125 0 Temperature [°C] 1.2 1.2 1.0 1.0 0.8 0.6 0.4 0.2 100 125 0.6 0.4 0.2 0 25 50 75 100 0.0 -25 125 0 25 50 75 100 125 Temperature [°C] Figure 12. Shutdown Delay Current (IDELAY) vs. TA Figure 13. Burst Mode High Threshold Voltage (Vburh) vs. TA 1.2 1.2 1.0 1.0 Normalized Normalized 75 0.8 Temperature [°C] 0.8 0.6 0.4 0.2 0.0 -25 50 Figure 11. Feedback Source Current (IFB) vs. TA Normalized Normalized Figure 10. Blanking Time (tB) vs. TA 0.0 -25 25 Temperature [°C] 0.8 0.6 0.4 0.2 0 25 50 75 100 0.0 -25 125 Temperature [°C] 25 50 75 100 125 Temperature [°C] Figure 14. Burst Mode Low Threshold Voltage (Vburl) vs. TA © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 0 Figure 15. Peak Current Limit (ILIM) vs. TA www.fairchildsemi.com 10 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Typical Performance Characteristics (Continued) 1.2 1.2 1.0 1.0 Normalized Normalized Characteristic graphs are normalized at TA=25°C. 0.8 0.6 0.4 0.2 0.0 -25 0.8 0.6 0.4 0.2 0 25 50 75 100 0.0 -25 125 0 Temperature [°C] 50 75 100 125 Figure 17. Sync Low Threshold Voltage (VSL) vs. TA 1.2 1.2 1.0 1.0 Normalized Normalized Figure 16. Sync High Threshold (VSH) vs. TA 0.8 0.6 0.4 0.2 0.0 -25 25 Temperature [°C] 0.8 0.6 0.4 0.2 0 25 50 75 100 0.0 -25 125 Temperature [°C] Figure 18. Shutdown Feedback Voltage (VSD) vs. TA © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 0 25 50 75 100 125 Temperature [°C] Figure 19. Over-Voltage Protection (VOP) vs. TA www.fairchildsemi.com 11 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Typical Performance Characteristics (Continued) 1. Startup: At startup, an internal high-voltage current source supplies the internal bias and charges the external capacitor (Ca) connected to the VCC pin, as illustrated in Figure 20. When VCC reaches 12V, the FPS™ begins switching and the internal high-voltage current source is disabled. The FPS continues its normal switching operation and the power is supplied from the auxiliary transformer winding unless VCC goes below the stop voltage of 8V. Vref VCC Idelay VFB VO IFB 3 FOD817A SenseFET OSC D1 CB D2 3R + VFB* KA431 Gate driver R - VDC OLP VSD Rsense FSQ0365RN Rev. 00 Ca Figure 21. Pulse-Width-Modulation (PWM) Circuit VCC 2 5 Vstr ICH Vref 8V/12V VCC good FSQ0365RN Rev.00 Internal Bias 3. Synchronization: The FSQ-series employs a valley switching technique to minimize the switching noise and loss. The basic waveforms of the valley switching converter are shown in Figure 22. To minimize the MOSFET's switching loss, the MOSFET should be turned on when the drain voltage reaches its minimum value, as shown in Figure 22. The minimum drain voltage is indirectly detected by monitoring the VCC winding voltage, as shown in Figure 22. Vds Figure 20. Startup Circuit 2. Feedback Control: FPS employs Current Mode control, as shown in Figure 21. An opto-coupler (such as FOD817A) and shunt regulator (such as KA431) are often used to implement the feedback network. Comparing the feedback voltage with the voltage across the RSENSE resistor makes it possible to control the switching duty cycle. When the reference pin voltage of the shunt regulator exceeds the internal reference voltage of 2.5V, the opto-coupler LED current increases, pulling down the feedback voltage and reducing the duty cycle. This event typically occurs when input voltage is increased or output load is decreased. 2.1 Pulse-by-Pulse Current Limit: Because Current Mode control is employed, the peak current through the SenseFET is limited by the inverting input of PWM comparator (VFB*), as shown in Figure 21. Assuming that the 0.9mA current source flows only through the internal resistor (3R + R = 2.8kΩ), the cathode voltage of diode D2 is about 2.5V. Since D1 is blocked when the feedback voltage (VFB) exceeds 2.5V, the maximum voltage of the cathode of D2 is clamped at this voltage, clamping VFB*. Therefore, the peak value of the current through the SenseFET is limited. 2.2 Leading-Edge Blanking (LEB): At the instant the internal SenseFET is turned on, a high-current spike usually occurs through the SenseFET, caused by primary-side capacitance and secondary-side rectifier reverse recovery. Excessive voltage across the Rsense resistor would lead to incorrect feedback operation in the Current Mode PWM control. To counter this effect, the FPS employs a leading-edge blanking (LEB) circuit. This circuit inhibits the PWM comparator for a short time (tLEB) after the SenseFET is turned on. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 VRO VRO VDC tF Vsync Vovp (6V) 0.7V 0.2V 300ns Delay MOSFET Gate ON ON FSQ0365RN Rev.00 Figure 22. Valley Resonant Switching Waveforms 4. Protection Circuits: The FSQ-series has several self-protective functions, such as Overload Protection (OLP), Abnormal Over-Current protection (AOCP), Over-Voltage Protection (OVP), and Thermal Shutdown (TSD). All the protections are implemented as AutoRestart Mode. Once the fault condition is detected, switching is terminated and the SenseFET remains off. This causes VCC to fall. When VCC falls down to the Under-Voltage Lockout (UVLO) stop voltage of 8V, the protection is reset and the startup circuit charges the VCC capacitor. When the VCC reaches the start voltage of 12V, the FSQ-series resumes normal operation. If the fault condition is not removed, the SenseFET remains off and VCC drops to stop voltage again. In this manner, www.fairchildsemi.com 12 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Functional Description VDS Power on Fault occurs VFB FSQ0365RN Rev.00 Overload protection 6.0V 2.8V Fault removed t12= CFB*(6.0-2.8)/Idelay t1 t2 t Figure 24. Overload Protection 8V t FSQ0365RN Rev. 00 Normal operation Fault situation Normal operation Figure 23. Auto-Restart Protection Waveforms 4.1 Overload Protection (OLP): Overload is defined as the load current exceeding its normal level due to an unexpected abnormal event. In this situation, the protection circuit should trigger to protect the SMPS. However, even when the SMPS is in the normal operation, the overload protection circuit can be triggered during load transition. To avoid this undesired operation, the overload protection circuit is designed to trigger only after a specified time to determine whether it is a transient situation or a true overload situation. Because of the pulse-by-pulse current limit capability, the maximum peak current through the SenseFET is limited, and therefore the maximum input power is restricted with a given input voltage. If the output consumes more than this maximum power, the output voltage (VO) decreases below the set voltage. This reduces the current through the opto-coupler LED, which also reduces the opto-coupler transistor current, thus increasing the feedback voltage (VFB). If VFB exceeds 2.8V, D1 is blocked and the 5µA current source starts to charge CB slowly up to VCC. In this condition, VFB continues increasing until it reaches 6V, when the switching operation is terminated, as shown in Figure 24. The delay for shutdown is the time required to charge CB from 2.8V to 6V with 5µA. A 20 ~ 50ms delay is typical for most applications. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 3R OSC PWM LEB 200ns S Q R Q Gate driver R Rsense 1 GND AOCP - 12V 4.2 Abnormal Over-Current Protection (AOCP): When the secondary rectifier diodes or the transformer pins are shorted, a steep current with extremely high-di/dt can flow through the SenseFET during the LEB time. Even though the FSQ-series has Overload Protection (OLP), it is not enough to protect the FSQ-series in that abnormal case, since severe current stress is imposed on the SenseFET until OLP triggers. The FSQ-series has an internal Abnormal Over-Current Protection (AOCP) circuit as shown in Figure 25. When the gate turn-on signal is applied to the power SenseFET, the AOCP block is enabled and monitors the current through the sensing resistor. The voltage across the resistor is compared with a preset AOCP level. If the sensing resistor voltage is greater than the AOCP level, the set signal is applied to the latch, resulting in the shutdown of the SMPS. + VCC FSQ0365RN Rev.00 VOCP Figure 25. Abnormal Over-Current Protection www.fairchildsemi.com 13 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter the auto-restart can alternately enable and disable the switching of the power SenseFET until the fault condition is eliminated. Because these protection circuits are fully integrated into the IC without external components, the reliability is improved without increasing cost. 4.4 Thermal Shutdown (TSD): The SenseFET and the control IC are built in one package. This makes it easy for the control IC to detect the abnormal over temperature of the SenseFET. If the temperature exceeds ~150°C, the thermal shutdown triggers. 5. Soft-Start: An internal soft-start circuit increases PWM comparator inverting input voltage with the SenseFET current slowly after it starts up. The typical soft-start time is 15ms. The pulsewidth to the power switching device is progressively increased to establish the correct working conditions for transformers, inductors, and capacitors. The voltage on the output capacitors is progressively increased with the intention of smoothly establishing the required output voltage. This helps prevent transformer saturation and reduces stress on the secondary diode during startup. 6. Burst Operation: To minimize power dissipation in Standby Mode, the FPS enters Burst-Mode operation. As the load decreases, the feedback voltage decreases. As shown in Figure 26, the device automatically enters Burst Mode when the feedback voltage drops below VBURL (350mV). At this point, switching stops and the output voltages start to drop at a rate dependent on standby current load. This causes the feedback voltage to rise. Once it passes VBURH (550mV), switching resumes. The feedback voltage then falls and the process repeats. Burst Mode alternately enables and disables switching of the power SenseFET, reducing switching loss in Standby Mode. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 VO VOset VFB 0.55V 0.35V IDS VDS time FSQ0365RN Rev.00 t1 Switching disabled t2 t3 Switching disabled t4 Figure 26. Waveforms of Burst Operation 7. Switching Frequency Limit: To minimize switching loss and Electromagnetic Interference (EMI), the MOSFET turns on when the drain voltage reaches its minimum value in valley switching operation. However, this causes switching frequency to increases at light load conditions. As the load decreases, the peak drain current diminishes and the switching frequency increases. This results in severe switching losses at light-load condition, as well as intermittent switching and audible noise. Because of these problems, the valley switching converter topology has limitations in a wide range of applications. To overcome this problem, FSQ-series employs a frequency-limit function, as shown in Figure 27 and Figure 28. Once the SenseFET is turned on, the next turn-on is prohibited during the blanking time (tB). After the blanking time, the controller finds the valley within the detection time window (tW ) and turns on the MOSFET, as shown in Figure 27 and Figure 28 (cases A, B, and C). If no valley is found during tW , the internal SenseFET is forced to turn on at the end of tW (case D). Therefore, FSQ devices have a minimum switching frequency of 55kHz and a maximum switching frequency of 67kHz, as shown in Figure 28. www.fairchildsemi.com 14 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter 4.3 Over-Voltage Protection (OVP): If the secondaryside feedback circuit malfunctions or a solder defect causes an opening in the feedback path, the current through the opto-coupler transistor becomes almost zero. Then VFB climbs up in a similar manner to the overload situation, forcing the preset maximum current to be supplied to the SMPS until the overload protection triggers. Because more energy than required is provided to the output, the output voltage may exceed the rated voltage before the overload protection triggers, resulting in the breakdown of the devices in the secondary side. To prevent this situation, an OVP circuit is employed. In general, the peak voltage of the sync signal is proportional to the output voltage and the FSQ-series uses a sync signal instead of directly monitoring the output voltage. If the sync signal exceeds 6V, an OVP is triggered, shutting down the SMPS. To avoid undesired triggering of OVP during normal operation, the peak voltage of the sync signal should be designed below 6V. When the resonant period is 2s 67kHz IDS IDS A A 59kHz 55kHz B C Constant frequency D tB=15s Burst mode ts IDS IDS B PO FSQ0365RN Rev. 00 tB=15s Figure 28. Switching Frequency Range ts IDS IDS C tB=15s ts IDS IDS tB=15s D tW=3s tsmax=18s FSQ0365RN Rev. 00 Figure 27. Valley Switching with Limited Frequency © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 15 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter tsmax=18s Application Input Voltage Range FPS Device DVD Player Power Supply FSQ0365RN Rated Output Power Output Voltage (Maximum Current) 19W 5.1V (1.0A) 3.4V (1.0A) 12V (0.4A) 16V (0.3A) 85-265VAC Features High efficiency ( >77% at universal input) Low standby mode power consumption (<1W at 230VAC input and 0.5W load) Reduce EMI noise through Valley Switching operation Enhanced system reliability through various protection functions Internal soft-start: 15ms Key Design Notes The delay time for overload protection is designed to be about 30ms with C107 of 47nF. If faster/slower triggering of OLP is required, C107 can be changed to a smaller/larger value (eg. 100nF for 60ms). The input voltage of Vsync must be higher than -0.3V. By proper voltage sharing by R106 & R107 resistors, the input voltage can be adjusted. The SMD-type 100nF capacitor must be placed as close as possible to VCC pin to avoid malfunction by abrupt pulsating noises and to improved surge immunity. Schematic C209 47pF T101 EER2828 RT101 5D-9 1 R105 100kΩ C104 10nF 630V R102 56kΩ C103 33F 400V L201 11 C210 47pF 2 R108 62Ω 12V, 0.4A 3 10 IC101 FSQ0365RN 1 5 3 Sync 8 Drain 7 Drain 6 Drain FB Vcc Vstr 4 3 4 C102 100nF,275VAC GND 1 C105 47nF 50V C202 470F 35V C201 470F 35V L202 D101 1N 4007 2 BD101 Bridge Diode 16V, 0.3A D201 UF4003 D202 UF4003 C203 470F 35V C204 470F 35V 12 C106 C107 100nF 22F 2 SMD 50V L203 6 R103 5Ω 4 D102 1N 4004 R104 12kΩ 5.1V, 1A D203 SB360 C205 1000F 10V C206 1000F 10V L204 5 9 ZD101 1N4746A 3.4V, 1A D204 SB360 D103 1N4148 R106 R107 6.2kΩ 6.2kΩ LF101 40mH C110 33pF 50V 8 C302 3.3nF C101 100nF 275VAC R201 510Ω R203 6.2kΩ R202 1kΩ TNR 10D471K C208 1000F 10V C207 1000F 10V R204 20kΩ C209 100nF IC202 FOD817A F101 FUSE IC201 KA431 AC IN R205 6kΩ FSQ0365RN Rev:00 Figure 29. Demo Circuit of FSQ0365RN © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 16 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Typical Application Circuit of FSQ0365RN EER2828 Np/2 12 Np/2 1 Np/2 2 3 Na 4 11 N16V N16V 10 N12V N12V 9 N 3.4V Na N5.1V 8 6mm 5 3mm N3.4V 7 Np/2 6 N 5.1V FSQ0365RN Rev: 00 Figure 30. Transformer Schematic Diagram of FSQ0365RN Table 1. Winding Specification No. Pin (sf) Wire Turns Winding Method Np/2 32 0.25 x 1 50 Center Solenoid Winding 4 Center Solenoid Winding 2 Center Solenoid Winding 16 Center Solenoid Winding 14 Center Solenoid Winding 18 Center Solenoid Winding 50 Center Solenoid Winding Insulation: Polyester Tape t = 0.050mm, 2-Layer 0.33 x 2 98 N3.4V Insulation: Polyester Tape t = 0.050mm, 2-Layer 0.33 x 1 69 N5V Insulation: Polyester Tape t = 0.050mm, 2-Layer 0.25 x 1 45 Na Insulation: Polyester Tape t = 0.050mm, 2-Layer 0.33 x 3 1012 N12V Insulation: Polyester Tape t = 0.050mm, 3-Layer 0.33 x 3 1112 N16V Insulation: Polyester Tape t = 0.050mm, 2-Layer 0.25 x 1 21 Np/2 Insulation: Polyester Tape t = 0.050mm, 2-Layer Table 2. Electrical Characteristics Pin Specification Remarks Inductance 1-3 1.4mH ± 10% 100kHz, 1V Leakage 1-3 25µH Maximum Short All Other Pins Core & Bobbin Core: EER2828 (Ae=86.66mm2) Bobbin: EER2828 © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 17 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Transformer Part Demo Board Part List Value Note Part Value Note Resistor Inductor R102 56k 1W L201 10µH R103 5 1/2W L202 10µH R104 12k 1/4W L203 4.9µH R105 100k 1/4W L204 4.9µH R106 6.2k 1/4W R107 6.2k 1/4W D101 IN4007 R108 62 1W D102 IN4004 R201 510 1/4W ZD101 1N4746A R202 1k 1/4W D103 1N4148 R203 6.2k 1/4W D201 UF4003 R204 20k 1/4W D202 UF4003 R205 6k 1/4W D203 SB360 D204 SB360 Capacitor Diode C101 100nF/275VAC Box Capacitor C102 100nF/275VAC Box Capacitor C103 33µF/400V Electrolytic Capacitor IC101 FSQ0365RN FPS™ C104 10nF/630V Film Capacitor IC201 KA431 (TL431) Voltage reference C105 47nF/50V Mono Capacitor IC202 FOD817A Opto-coupler C106 100nF/50V SMD (1206) C107 22µF/50V Electrolytic Capacitor C110 33pF/50V Ceramic Capacitor C201 470µF/35V Electrolytic Capacitor C202 470µF/35V Electrolytic Capacitor C203 470µF/35V Electrolytic Capacitor C204 470µF/35V Electrolytic Capacitor C205 1000µF/10V Electrolytic Capacitor C206 1000µF/10V Electrolytic Capacitor C207 1000µF/10V Electrolytic Capacitor C208 1000µF/10V Electrolytic Capacitor C209 100nF /50V Ceramic Capacitor © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 IC Fuse Fuse 2A/250V RT101 5D-9 NTC Bridge Diode BD101 2KBP06M2N257 Bridge Diode Line Filter LF101 40mH Transformer T101 Varistor TNR 10D471K www.fairchildsemi.com 18 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Table 3. [ .400 10.15 .373 9.46 A ] .036 [0.9 TYP] (.092) [Ø2.337] (.032) [R0.813] PIN #1 .250±.005 [6.35±0.13] PIN #1 B TOP VIEW OPTION 1 TOP VIEW OPTION 2 [ ] .070 1.78 .045 1.14 .310±.010 [7.87±0.25] .130±.005 [3.3±0.13] .210 MAX [5.33] 7° TYP 7° TYP C .015 MIN [0.38] .140 3.55 .125 3.17 [ ] .021 0.53 .015 0.37 .001[.025] .300 [7.62] [ ] C .100 [2.54] .430 MAX [10.92] NOTES: .060 MAX [1.52] A. CONFORMS TO JEDEC REGISTRATION MS-001, VARIATIONS BA B. CONTROLING DIMENSIONS ARE IN INCHES REFERENCE DIMENSIONS ARE IN MILLIMETERS C. DOES NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCHES OR 0.25MM. D. DOES NOT INCLUDE DAMBAR PROTRUSIONS. DAMBAR PROTRUSIONS SHALL NOT EXCEED .010 INCHES OR 0.25MM. E. DIMENSIONING AND TOLERANCING PER ASME Y14.5M-1994. [ +0.127 .010+.005 -.000 0.254-0.000 ] N08EREVG Figure 31. 8-Lead, Dual Inline Package (DIP) Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 19 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Package Dimensions FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter Package Dimensions (Continued) MKT-MLSOP08ArevA Figure 32. 8-Lead, MLSOP Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/. © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 20 FSQ0365/0265/0165/321 — Green Mode Fairchild Power Switch (FPS™) for Valley Switching Converter © 2007 Fairchild Semiconductor Corporation FSQ0365, FSQ0265, FSQ0165, FSQ321 • Rev. 1.0.6 www.fairchildsemi.com 21