FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 Green Mode Fairchild Power Switch (FPS™) Features Description The highly integrated FSBH-series consists of an integrated current-mode Pulse Width Modulator (PWM) and an avalanche-rugged 700V SenseFET. It is specifically designed for high-performance offline Switch Mode Power Supplies (SMPS) with minimal external components. Brownout Protection with Hysteresis Built-In 5ms Soft-Start Function Internal Avalanche-Rugged 700V SenseFET No Acoustic Noise During Light-Load Operation High-Voltage Startup Linearly Decreasing PWM Frequency to 18KHz Peak-Current-Mode Control Cycle-by-Cycle Current Limiting Leading-Edge Blanking (LEB) Synchronized Slope Compensation Internal Open-Loop Protection VDD Under-Voltage Lockout (UVLO) VDD Over-Voltage Protection (OVP) Internal Auto-Restart Circuit (OVP, OTP) Constant Power Limit (Full AC Input Range) Internal OTP Sensor with Hysteresis VIN Pin for Pull-HIGH Latch Function and PullLOW Auto-Recovery Protection Applications General-purpose switch-mode power supplies and flyback power converters, including: Auxiliary Power Supply for PC and Server Adapter for Camcorder SMPS for VCR, SVR, STB, DVD & DVCD Player, Printer, Facsimile, and Scanner © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 The integrated PWM controller features include a proprietary green-mode function that provides off-time modulation to linearly decrease the switching frequency at light-load conditions to minimize standby power consumption. To avoid acoustic-noise problems, the minimum PWM frequency is set above 18kHz. This green-mode function enables the power supply to meet international power conservation requirements. The PWM controller is manufactured using the BiCMOS process to further reduce power consumption. The FSBH-series turns off some internal circuits to improve power saving when VFB is lower than 1.6V, which allows an operating current of only 2.5mA. The FSBH-series has built-in synchronized slope compensation to achieve stable peak-current-mode control. The proprietary external line compensation ensures constant output power limit over a wide AC input voltage range, from 90VAC to 264VAC. The FSBH-series provides many protection functions. In addition to cycle-by-cycle current limiting, the internal open-loop protection circuit ensures safety when an open-loop or output short occurs. PWM output is disabled until VDD drops below the VTH-OLP, then the controller starts up again. As long as VDD exceeds 28V, the internal OVP circuit is triggered. Compared with a discrete MOSFET and controller or RCC switching converter solution, the FSBH-series reduces total component count, design size, and weight; while increasing efficiency, productivity, and system reliability. These devices provide a basic platform that is well suited for the design of costeffective flyback converters, such as in PC auxiliary power supplies. www.fairchildsemi.com FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) April 2010 Sense FET Operating Temperature Range FSBH0F70ANY 0.5A 700V -40°C to +105°C FSBH0170ANY 1.0A 700V -40°C to +105°C Part Number FSBH0270ANY 2.0A 700V -40°C to +105°C FSBH0170NY 1.0A 700V -40°C to +105°C FSBH0270NY 2.0A 700V -40°C to +105°C FSBH0370NY 3.0A 700V -40°C to +105°C VIN Pin (PIN #4) Packing Method Package Not Available 8-Pin Dual In-Line Package (DIP) Tube Enabled Application Diagram HV Drain VIN FB VDD GND Figure 1. Typical Flyback Application Output Power Table (1) (2) 230VAC ± 15% Product (3) Adapter FSBH0F70A 7W 85-265VAC (4) Open Frame 10W (3) Adapter 6W (4) Open Frame 8W FSBH0170/A 10W 15W 9W 13W FSBH0270/A 14W 20W 11W 16W FSBH0370 17.5W 25W 13W 19W Notes: 1. The maximum output power can be limited by junction temperature. 2. 230 VAC or 100/115 VAC with doublers. 3. Typical continuous power in a non-ventilated enclosed adapter with sufficient drain pattern as a heat sink at 50°C ambient. 4. Maximum practical continuous power in an open-frame design with sufficient drain pattern as a heat sink at 50°C ambient. © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 2 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Ordering Information FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 Green — Mode Fairchild Power Switch (FPS™) Internal Block Diagrams Figure 2. FSBH0170, FSBH0270, FSBH0370 Internal Block Diagram Figure 3. FSBH0F70A, FSBH0170A, FSBH0270A Internal Block Diagram © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 3 8 F – Fairchild Logo Z – Plant Code X – 1-Digit Year Code Y – 1-Digit Week Code TT – 2-Digit Die Run Code T – Package Type (N:DIP) P – Y: Green Package M – Manufacture Flow Code 8 ZXYTT BH0F70A TPM ZXYTT BH0170A TPM 1 1 8 8 ZXYTT BH0270A TPM ZXYTT BH0170 TPM 1 1 8 8 ZXYTT BH0270 TPM ZXYTT BH0370 TPM 1 1 Figure 4. Pin Configuration and Top Mark Information Pin Definitions Pin # Name 1 GND Ground. SenseFET source terminal on primary side and internal controller ground. 2 VDD Power Supply. The internal protection circuit disables PWM output as long as VDD exceeds the OVP trigger point. 3 FB Feedback. The signal from the external compensation circuit is fed into this pin. The PWM duty cycle is determined in response to the signal on this pin and the internal current-sense signal. VIN Line-Voltage Detection. The line-voltage detection is used for brownout protection with hysteresis and constant output power limit over universal AC input range. This pin has additional protections that are pull-HIGH latch and pull-LOW auto recovery, depending on the application. NC No Connection for FSBH0F70A, FSBH0170A and FSBH0270A. 5 HV Startup. For startup, this pin is pulled HIGH to the line input or bulk capacitor via resistors. 6 Drain SenseFET Drain. High-voltage power SenseFET drain connection. 7 Drain SenseFET Drain. High-voltage power SenseFET drain connection. 8 Drain SenseFET Drain. High-voltage power SenseFET drain connection. 4 Description © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 4 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Pin Configuration 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. Symbol VDRAIN IDM Parameter Drain Pin Voltage Min. (5,6) Drain Current Pulsed FSBH0x70/A (7) (8) Max. Unit 700 V FSBH0F70A 1.5 FSBH0170/A 4.0 FSBH0270/A 8.0 FSBH0370 12.0 FSBH0F70A 10 FSBH0170/A 50 FSBH0270/A 140 FSBH0370 230 EAS Single Pulsed Avalanche Energy VDD DC Supply Voltage VFB FB Pin Input Voltage -0.3 -0.3 A mJ 30 V 7.0 V VIN VIN Pin Input Voltage 7.0 V VHV HV Pin Input Voltage 700 V PD Power Dissipation (TA<50°C) 1.5 W θJA Junction-to-Air Thermal Resistance 80 °C/W θJC Junction-to-Case Thermal Resistance 20 °C/W TJ TSTG TL ESD (9) °C +150 °C +260 °C Operating Junction Temperature Internally limited Storage Temperature Range -55 Lead Temperature (Wave Soldering or IR, 10 Seconds) Electrostatic Discharge Capability, All pins except HV pin Human Body Model: JESD22-A114 3 Charged Device Model: JESD22-C101 1 kV Notes: 5. All voltage values, except differential voltages, are given with respect to the network ground terminal. 6. Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. 7. Non-repetitive rating: pulse width is limited by maximum junction temperature. 8. L = 51mH, starting TJ = 25°C. 9. Internally Limited of TJ refers to TOTP Recommended Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings. Symbol TA Parameter Conditions Operating Ambient Temperature © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 Min. -40 Typ. Max. Unit +105 °C www.fairchildsemi.com 5 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Absolute Maximum Ratings VDD=15V and TA=25°C unless otherwise specified. Symbol Parameter SenseFET Section Condition Min. VDS = 700V, VGS = 0V 700 BVDSS Drain-Source Breakdown Voltage IDSS Zero-Gate-Voltage Drain Current FSBH0x70/A CISS COSS FSBH0x70/A VDS = 560V, VGS = 0V, TC = 125°C 200 Drain-Source On(11) State Resistance Input Capacitance Output Capacitance Reverse Transfer Capacitance Turn-On Delay Time 19.00 8.80 11.00 6.00 7.20 FSBH0370 4.00 4.75 FSBH0F70A 162 211 250 325 550 715 FSBH0370 315 410 FSBH0F70A 18 24 25 33 38 50 47 61 FSBH0170/A FSBH0270/A FSBH0170/A FSBH0270/A FSBH0170/A FSBH0270/A VGS = 10V, ID = 0.5A VGS = 0V, VDS = 25V, f = 1MHz VGS = 0V, VDS = 25V, f = 1MHz FSBH0F70A 3.8 5.7 FSBH0170/A 10.0 15.0 17.0 26.0 9.0 24.0 FSBH0270/A VGS = 0V, VDS = 25V, f = 1MHz FSBH0F70A 9.5 29.0 FSBH0170/A 12.0 34.0 20.0 50.0 11.2 33.0 19 48 4 18 15 40 34 78 33.0 76.0 FSBH0270/A VDS = 350V, ID = 1.0A FSBH0370 FSBH0F70A tR Rise Time FSBH0170/A FSBH0270/A VDS = 350V, ID = 1.0A FSBH0370 FSBH0F70A tD(OFF) Turn-Off Delay Time FSBH0170/A FSBH0270/A VDS = 350V, ID = 1.0A FSBH0370 tF Fall Time μA 14.00 FSBH0370 tD(ON) Unit V 50 FSBH0370 CRSS Max. VDS = 700V, VGS = 0V FSBH0F70A RDS(ON) Typ. (10) 30.0 70.0 55.0 120.0 28.2 67.0 FSBH0F70A 42 94 FSBH0170/A 10 30 25 60 32 74 FSBH0270/A VDS = 350V, ID = 1.0A FSBH0370 Ω pF pF pF ns ns ns ns Continued on the following page… © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 6 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Electrical Characteristics VDD=15V and TA=25°C unless otherwise specified. Symbol Parameter Condition Min. Typ. Max. Unit Control Section VDD Section VDD-ON Start Threshold Voltage 11 12 13 V VDD-OFF Minimum Operating Voltage 7 8 9 V IDD-ST Startup Current FSBH0170 FSBH0270 FSBH0370 VDD-ON – 0.16V FSBH0F70A FSBH0170A FSBH0270A VDD-ON – 0.16V 240 320 400 30 µA IDD-OP Operating Supply Current VDD = 15V, VFB = 3V 3.0 3.5 4.0 mA IDD-ZDC Operating Current for VFB<VFB-ZDC VDD = 12V, VFB = 1.6V 1.5 2.5 3.5 mA VTH-OLP+0.1V IDD-OLP Internal Sink Current 30 70 90 µA VTH-OLP IDD-OLP Off Voltage 5 6 7 V VDD-OVP VDD Over-Voltage Protection 27 28 29 V tD-VDD-OVP VDD Over-Voltage Protection Debounce Time 75 130 200 µs 1.5 3.5 5.0 mA 1 20 µA 94 100 106 kHz 14 18 22 kHz HV Section IHV IHV-LC Maximum Current Drawn from HV Pin HV 120VDC, VDD = 0V with 10µF Leakage Current after Startup HV = 700V, VDD = VDD-OFF+1V Oscillator Section fOSC Frequency in Nominal Mode fOSC-G Green-Mode Frequency DMAX Maximum Duty Cycle Center Frequency 85 % fDV Frequency Variation vs. VDD Deviation VDD = 11V to 22V 5 % fDT Frequency Variation vs. Temperature (10) Deviation TA = -25 to 85°C 5 % VIN Section (FSBH0170, FSBH0270, FSBH0370) VIN-ON PWM Turn-On Threshold Voltage 1.08 1.13 1.18 V VIN-OFF PWM Turn-Off Threshold Voltage VIN-ON – 0.48 VIN-ON – 0.60 V tIN-OFF PWM Turn-Off Debounce Time VIN-ON – 0.54 500 4.4 4.7 5.0 VIN-H Pull-HIGH Latch Trigger Level tIN-H Pull-HIGH Latch Debounce Time VIN-L Pull-LOW Auto-Recovery Trigger Level ms 100 V µs 0.2 0.3 0.4 1/4.5 1/4.0 1/3.5 V/V 7 kΩ V Feedback Input Section AV FB Voltage to Current-Sense Attenuation ZFB Input Impedance 4 Continued on the following page… © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 7 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Electrical Characteristics (Continued) VDD=15V and TA=25°C unless otherwise specified. Symbol VFB-OPEN Parameter Condition Output High Voltage FB Pin Open Min. Typ. Max. 5.5 Unit V VFB-N Green-Mode Entry FB Voltage 2.3 2.5 2.7 V VFB-G Green-Mode Ending FB Voltage 1.9 2.0 2.1 V VFB-ZDC VFB-OLP tD-OLP Zero Duty Cycle FB Voltage FB Open-Loop Trigger Level tSS V 5.2 5.4 5.6 V FSBH0x70/A 4.4 4.6 4.8 V 50 56 59 ms FB Open-Loop Protection Delay Current-Sense Section ILIM 1.6 FSBH0F70A (14) Peak Current Limit FSBH0F70A VIN Open 0.63 0.73 0.83 FSBH0170/A VIN = 1.2V / VIN Open 0.70 0.80 0.90 FSBH0270/A VIN = 1.2V / VIN Open 0.90 1.00 1.10 FSBH0370 VIN = 1.2V 1.10 1.20 1.30 4.5 5.0 5.5 (10) Period During Soft-Start Time A ms Constant Power Limit (FSBH0170, FSBH0270, FSBH0370) VLMT1 Threshold Voltage 1 for Current Limit VIN = 1.2V 0.73 0.80 0.87 V VLMT2 Threshold Voltage 2 for Current Limit VIN = 3.6V 0.56 0.63 0.70 V FSBH0F70A 0.97 1.00 1.03 V FSBH0170A/0270A 0.77 0.80 0.83 V +142 +150 °C Current Limit (FSBH0F70A, FSBH0170A, FSBH0270A) VLMT Threshold Voltage for Current Limit Over-Temperature Protection Section (OTP) TOTP TRESTART Protection Junction Temperature Restart Junction Temperature (10, 12) +135 (10, 13) TOTP-25 °C Notes: 10. These parameters, although guaranteed, are not 100% tested in production. 11. Pulse test: pulse width ≤ 300ìs, duty ≤ 2%. 12. When activated, the output is disabled and the latch is turned off. 13. The threshold temperature for enabling the output again and resetting the latch after over-temperature protection has been activated. 14. These parameters, although guaranteed, are tested in wafer process. PWM Frequency fOSC fOSC-G VFB-ZDC VFB-G VFB-N VFB Figure 5. VFB vs. PWM Frequency © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 8 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Electrical Characteristics (Continued) 14 3.02 12 3.00 2.98 2.96 IDD-OP(µA) IDD-ST(µA) 10 8 6 2.94 2.92 4 2.90 2 2.88 0 2.86 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 Temperature(°C) 12.4 8.3 12.2 8.2 12.0 8.1 11.8 11.6 11.4 65 80 95 110 125 95 110 125 95 110 125 8.0 7.9 7.8 11.2 7.7 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 Temperature(°C) Figure 8. 20 35 50 65 80 Temperature(°C) VDD-ON vs. Temperature Figure 9. VDD-OFF vs. Temperature 6.6 28.42 6.4 28.41 6.2 28.40 V DD-OVP(V) V TH-OLP(V) 50 Figure 7. IDD-OP vs. Temperature V DD-OFF (V) V DD-ON (V) Figure 6. IDD-ST vs. Temperature 6.0 5.8 5.6 28.39 28.38 28.37 5.4 28.36 5.2 5.0 28.35 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 Temperature(°C) Figure 10. 35 50 65 80 Temperature(°C) VTH-OLP vs. Temperature Figure 11. 4.0 7 3.5 6 VDD-OVP vs. Temperature 5 IHV-LC(µA) 3.0 IHV(mA) 35 Temperature(°C) 2.5 2.0 4 3 2 1.5 1 1.0 0 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 Temperature(°C) Figure 12. 20 35 50 65 80 95 110 125 Temperature(°C) IHV vs. Temperature © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 5 Figure 13. IHV-LC vs. Temperature www.fairchildsemi.com 9 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 Green — Mode Fairchild Power Switch (FPS™) Typical Characteristics (Continued) 101.5 19.2 101.0 19.1 FOSC-G(kHz) FOSC(kHz) 100.5 100.0 99.5 99.0 19.0 18.9 18.8 98.5 18.7 98.0 18.6 97.5 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 fOSC vs. Temperature Figure 15. 0.64 1.17 0.63 1.16 0.62 1.15 V IN-ON (V) V IN-OFF(V) Figure 14. 0.61 0.60 50 65 80 95 110 125 110 125 95 110 125 95 110 125 fOSC-G vs. Temperature 1.14 1.13 1.12 0.59 1.11 0.58 -40 -25 -10 5 20 35 50 65 80 95 110 -40 125 -25 -10 5 20 Figure 16. 35 50 65 80 95 Temperature(°C) Temperature(°C) VIN-OFF vs. Temperature Figure 17. 4.63 0.34 4.62 0.33 4.61 0.32 V IN-L(V) V IN-H (V) 35 Temperature(°C) Temperature(°C) 4.60 0.31 4.59 0.30 4.58 0.29 4.57 VIN-ON vs. Temperature 0.28 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 Temperature(°C) Figure 18. 35 50 65 80 Temperature(°C) VIN-H vs. Temperature Figure 19. 4.75 VIN-L vs. Temperature 2.60 4.70 2.55 4.60 V FB-N (V) V FB-OLP(V) 4.65 4.55 4.50 2.50 2.45 2.40 4.45 2.35 4.40 4.35 2.30 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 Temperature(°C) Figure 20. 20 35 50 65 80 Temperature(°C) VFB-OLP vs. Temperature © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 5 Figure 21. VFB-N vs. Temperature www.fairchildsemi.com 10 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Typical Characteristics (Continued) 2.20 1.800 2.15 1.700 2.05 V FB-ZDC (V) V FB-G(V) 2.10 2.00 1.95 1.600 1.500 1.400 1.90 1.300 1.85 1.80 1.200 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 Temperature(°C) VFB-G vs. Temperature Figure 23. 2.56 55.0 2.54 54.5 2.52 54.0 tD-OLP(ms) IDD-ZDC (mA) Figure 22. 35 50 65 80 95 110 125 110 125 Temperature(°C) 2.50 2.48 VFB-ZDC vs. Temperature 53.5 53.0 2.46 52.5 2.44 52.0 51.5 2.42 -40 -25 -10 5 20 35 50 65 80 95 110 -40 125 -25 -10 Figure 24. IDD-ZDC vs. Temperature © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 5 20 35 50 65 80 95 Temperature(°C) Temperature(°C) Figure 25. tD-OLP vs. Temperature www.fairchildsemi.com 11 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Typical Characteristics (Continued) Startup Operation Brown-In/Out Function The HV pin is connected to bulk voltage through an external resistor, RHV, as shown in Figure 26. When AC voltage is applied to power system, an internal HV startup circuit provides a high current (around 3.5mA) to charge an external VDD capacitor until VDD voltage exceeds the turn-on threshold voltage (VDD-ON). For better power consumption, the HV startup circuit shuts down during normal operation. The external VDD capacitor and auxiliary winding maintain the VDD voltage and provide operating current to controller. FSBH0x70 has a built-in internal brown-in/out protection comparator monitoring voltage of VIN pin. Figure 28 shows a resistive divider with low-pass filtering for linevoltage detection on the VIN pin. Figure 28. Once the VIN pin voltage is lower than 0.6V and lasts for 500ms, the PWM gate is disabled to protect the system from over current. FSBH0x70 starts up as VIN increases above 1.1V. Because the divider resistors of the VIN pin are connected behind the bridge, the ratio calculation for brownout in PFC and non-PFC system are different, as shown in Figure 29. The formulas are provided in the following equations: Figure 26. Startup Circuit Slope Compensation The FSBH-series is designed for flyback power converters. The peak-current-mode control is used to optimize system performance. Slope compensation is added to reduce current loop gain and improve power system stability. The FSBH-series has a built-in, synchronized, positive slope for each switching cycle. Brownout with PFC: RC 2 ⋅ 2VAC _ OUT ⋅ = 0.6 RA + RB + RC π RC ⋅ 2VAC _ OUT = 0.6 RA + RB + RC The FSBH-series has an internal soft-start circuit that reduces the SenseFET switching current during power system startup. The characteristic curve of soft-start time versus VLMT level is shown in Figure 27. The VLMT level slopes up like a six-step staircase. In doing so, power system can smoothly build up the rated output voltage and effectively reduce voltage stress on the PWM switch and output diode. (2) Brown-in level is determined by: VAC _ IN = Soft-Start Function © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 (1) Brownout with non-PFC: Soft-Start Figure 27. Brown-In/Out Function on VIN Pin Figure 29. 1.1 RA + RB + RC ⋅ RC 2 (3) VIN Level According to PFC Operation www.fairchildsemi.com 12 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Functional Description H/L Line Over-Power Compensation The VIN pin functions are disabled from FSBH0x70A, but FSBH0x70A has brown-in protection in the VDD pin. There is a discharge current internal from VDD to ground during startup. The HV source current must be larger than IDD-ST to charge the capacitor of VDD. Therefore, the brown-in level can be determined by RHV according to the equation: To limit the output power of the converter constantly, high/low line over-power compensation is included. Sensing the converter input voltage through the VIN pin, the high/low line compensation function generates a relative peak-current-limit threshold voltage for constant power control, as shown in Figure 32. RHV = 2VAC − 12 IDD −ST (4) Green-Mode Operation The FSBH-series uses feedback voltage (VFB) as an indicator of the output load and modulates the PWM frequency, as shown in Figure 30, such that the switching frequency decreases as load decreases. In heavy load conditions, the switching frequency is 100kHz. Once VFB decreases below VFB-N (2.5V), the PWM frequency starts to linearly decrease from 100kHz to 18kHz for reducing switching losses. As VFB decreases below VFB-G (2.0V), the switching frequency is fixed at 18kHz and FSBH-series enters “deep” green mode to reduce the standby power consumption. Figure 32. Constant Power Control Protections The FSBH-series provides full protection functions to prevent the power supply and the load from being damaged. The protection features include: Latch/Auto-Recovery Function Besides the brownout protection and high/low line overpower compensation, the FSBH0170/0270/0370 has additional protections via the VIN pin, such as pullHIGH latch and pull-LOW auto-recovery that depends on the application. As shown in Figure 33, VIN level is higher than 4.7V, FSBH-series is latched until the VDD is discharged. FSBH-series is auto-recovery when the VIN level is lower than 0.3V. Figure 30. PWM Frequency As VFB decreases below VFB-ZDC (1.6V), FSBH-series enters into burst-mode operation. When VFB drops below VFB-ZDC, FSBH-series stops switching and the output voltage starts to drop, which causes the feedback voltage to rise. Once VFB rises above VFB-ZDC, switching resumes. Burst mode alternately enables and disables switching, thereby reducing switching loss to improve power saving, as shown in Figure 31. VO Figure 33. VIN Pin Function Open-Loop / Overload Protection (OLP) When the upper branch of the voltage divider for the shunt regulator (KA431 shown) is broken, as shown in Figure 34, or over current or output short occurs, there is no current flowing through the opto-coupler transistor, which pulls the feedback voltage up to 6V. VFB VFB.ZDC (1.6V) IDrain Switching Disabled When feedback voltage is above 4.6V for longer than 56ms, OLP is triggered. This protection is also triggered when the SMPS output drops below the nominal value longer than 56ms due to the overload condition. Switching Disabled Figure 31. Burst-Mode Operation © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 13 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) Brown-In Function of FSBH0x70A VFB Vo PWM 3R Over-Temperature Protection (OTP) The SenseFET and the control IC are integrated, making it easier to detect the temperature of the SenseFET. When the temperature exceeds approximately 142°C, thermal shutdown is activated. R KA431 Feedback Open Loop 56ms OLP 4.6V Figure 34. OLP Operation © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 14 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) VDD Over-Voltage Protection (OVP) VDD over-voltage protection prevents IC damage caused by over voltage on the VDD pin. The OVP is triggered when VDD voltage reaches 28V. Debounce time (typically 130µs) prevents false trigger by switching noise. 6V FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 Green — Mode Fairchild Power Switch (FPS™) Physical Dimensions 9.83 9.00 6.67 6.096 8.255 7.61 3.683 3.20 5.08 MAX 7.62 0.33 MIN 3.60 3.00 (0.56) 2.54 0.56 0.355 0.356 0.20 9.957 7.87 1.65 1.27 7.62 NOTES: UNLESS OTHERWISE SPECIFIED A) THIS PACKAGE CONFORMS TO JEDEC MS-001 VARIATION BA B) ALL DIMENSIONS ARE IN MILLIMETERS. C) DIMENSIONS ARE EXCLUSIVE OF BURRS, MOLD FLASH, AND TIE BAR EXTRUSIONS. D) DIMENSIONS AND TOLERANCES PER ASME Y14.5M-1994 E) DRAWING FILENAME AND REVSION: MKT-N08FREV2. Figure 35. 8-Pin Dual In-Line 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/. © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 15 FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 — Green Mode Fairchild Power Switch (FPS™) © 2009 Fairchild Semiconductor Corporation FSBH0F70A, FSBH0170/A, FSBH0270/A, FSBH0370 • Rev. 1.0.3 www.fairchildsemi.com 16