Green Current-Mode PWM Controller

FAN7602B — Green Current-Mode PWM Controller March 2007 FAN7602B Green Current-Mode PWM Controller Features Green Current-Mode PWM Control Fixed 65kHz Operation Internal High-Voltage Start-up Switch Burst-Mode Operation Line Voltage Feedforward to Limit Maximum Power Line Under-Voltage Protection Latch Protection & Internal Soft-Start (10ms) Function Overload Protection Over-Voltage Protection Low Operation Current: 1mA Typical 8-pin DIP/SOP Description The FAN7602B is a green current-mode PWM controller. It is specially designed for off-line adapter applications; DVDP, VCR, LCD monitor applications; and auxiliary power supplies. The internal high-voltage start-up switch and the burstmode operation reduce the power loss in standby mode. As a result, it is possible to supply 0.5W load, limiting the input power under 1W when the input line voltage is 265VAC. On no-load condition, input power is under 0.3W. The maximum power can be limited constantly, regardless of the line voltage change, using the power limit function. The switching frequency is internally fixed at 65kHz. The FAN7602B includes various protections for the system reliability and the internal soft-start prevents the output voltage over-shoot at start-up. www.DataSheet4U.com Applications Adapter LCD Monitor Power Auxiliary Power Supply Related Application Notes AN6014 - Green Current Mode PWM Controller FAN7602 Ordering Information Part Number FAN7602BN FAN7602BM FAN7602BMX -25°C to +125°C Yes Operating Temp. Range Pb-Free Package 8-DIP 8-SOP Packing Method Rail Rail Tape & Reel Marking Code FAN7602B FAN7602B FAN7602B © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Typical Application Diagram FAN7602B Figure 1. Typical Flyback Application Internal Block Diagram VSTR 8 6 VCC LUVP 1 2V/1.5V LUVP OLP OVP Latch Auto Restart Protection Latch Protection Reset Circuit VCC OVP SS End 19V 5V Ref UVLO 12V/8V 10ms Soft Start SS End PWM Block 65kHz clock Delay Circuit Latch/ Plimit 0.95V/0.88V 2 4V Plimit Offset Generator Plimit Offset Soft Start Latch PWM+ OLP Soft Start Driver Circuit Plimit Offset 5 OUT 3 CS/FB Power Limit Plimit Offset OLP 4 GND Figure 2. Functional Block Diagram of FAN7602B © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 2 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Pin Assignments VSTR 8 NC 7 VCC 6 Out 5 FAN7602B YWW 1 LUVP 2 Latch/ Plimit 3 CS/FB 4 GND Figure 3. Pin Configuration (Top View) Pin Definitions Pin # 1 2 Name LUVP Latch/Plimit Description Line Under-Voltage Protection Pin. This pin is used to protect the set when the input voltage is lower than the rated input voltage range. Latch Protection and Power Limit Pin. When the pin voltage exceeds 4V, the latch protection works; the latch protection is reset when the VCC voltage is lower than 5V. For the power limit function, the OCP level decreases as the pin voltage increases. Current Sense and Feedback Pin. This pin is used to sense the MOSFET current for the current mode PWM and OCP. The output voltage feedback information and the current sense information are added using an external RC filter. Ground Pin. This pin is used for the ground potential of all the pins. For proper operation, the signal ground and the power ground should be separated. Gate Drive Output Pin. This pin is an output pin to drive an external MOSFET. The peak sourcing current is 450mA and the peak sinking current is 600mA. For proper operation, the stray inductance in the gate driving path must be minimized. Supply Voltage Pin. IC operating current and MOSFET driving current are supplied using this pin. No Connection. Start-up Pin. This pin is used to supply IC operating current during IC start-up. After start-up, the internal JFET is turned off to reduce power loss. 3 4 5 6 7 8 CS/FB GND OUT VCC NC VSTR © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 3 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Absolute Maximum Ratings 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 VCC IOH, IOL VCS/FB VLUVP VLatch VSTR TJ TA TSTG PD VESD_HBM VESD_MM VESD_CDM Supply Voltage Parameter Peak Drive Output Current CS/FB Input Voltage LUVP Input Voltage Latch/Plimit Input Voltage VSTR Input Voltage Operating Junction Temperature Operating Temperature Range Storage Temperature Range Power Dissipation ESD Capability, Human Body Model ESD Capability, Machine Model ESD Capability, Charged Device Model Value 20 +450/-600 -0.3 to 20 -0.3 to 10 -0.3 to 10 600 150 -25 to 125 -55 to 150 1.2 2.0 200 500 Unit V mA V V V V °C °C °C W kV V V Thermal Impedance Symbol θJA Note: 1. Regarding the test environment and PCB type, please refer to JESD51-2 and JESD51-10. Parameter Thermal Resistance, Junction-to-Ambient 8-DIP Value 100 Unit °C/W © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 4 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Electrical Characteristics VCC = 14V, TA = -25°C~125°C, unless otherwise specified Symbol START UP SECTION ISTR Vth(start) Vth(stop) HY(uvlo) ISTR ICC tSS fOSC VCS/FB1 tD DMAX DMIN VCS/FB2 VCS/FB3 KPlimit VOH VOL tR tF VLatch tOLP tOLP_ST VOLP VLUVPoff VLUVPon VOVP Note: Parameter VSTR Start-up Current Start Threshold Voltage Stop Threshold Voltage UVLO Hysteresis Start-up Supply Current Operating Supply Current Soft-Start Time(1) Operating Frequency CS/FB Threshold Voltage Propagation Delay to Output Maximum Duty Cycle Minimum Duty Cycle Burst On Threshold Voltage Burst Off Threshold Voltage Offset Gain Output Voltage High Output Voltage Low Rising Time Falling (1) (1) Condition VSTR = 30V, TA = 25°C VCC increasing VCC decreasing Min. 0.7 11 7 3.6 Typ. 1.0 12 8 4.0 250 1.0 Max. 1.4 13 9 4.4 320 1.5 15 73 1.1 150 80 0 Unit mA V V V μA mA ms kHz V ns % % V V UNDER VOLTAGE LOCK OUT SECTION SUPPLY CURRENT SECTION TA = 25°C Output no switching 5 VCS/FB = 0.2V, TA = 25°C TA = 25°C 59 0.9 70 SOFT-START SECTION 10 65 1.0 100 75 PWM SECTION BURST MODE SECTION TA = 25°C TA = 25°C VLatch/Plimit = 2V, TA = 25°C TA = 25°C, Isource = 100mA TA = 25°C, Isink = 100mA TA = 25°C, CL = 1nF TA = 25°C, CL= 1nF 3.6 (1) 0.84 0.77 0.12 11.5 0.95 0.88 0.16 12.0 1.0 45 35 4.0 22 37 0 1.06 0.99 0.20 14.0 2.5 150 150 4.4 24 44 0.1 2.1 1.6 20 POWER LIMIT SECTION OUTPUT SECTION V V ns ns V ms ms V V V V Time(1) PROTECTION SECTION Latch Voltage Overload Protection Time Overload Protection Time at Startup Overload Protection Level Line Under-Voltage Protection On to Off Line Under-Voltage Protection Off to On Over-Voltage Protection TA = 25°C TA = 25°C TA = 25°C 1.9 1.4 18 20 30 2.0 1.5 19 1. These parameters, although guaranteed by design, are not tested in production. © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 5 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Typical Performance Characteristics 12.8 12.4 8.8 8.4 VTH[V] VTL[V] 12.0 11.6 11.2 -25 0 25 50 75 100 125 8.0 7.6 7.2 -25 0 25 50 75 100 125 Temperature [°C] Temperature [°C] Figure 4. Start Threshold Voltage vs. Temp. Figure 5. Stop Threshold Voltage vs. Temp. 4.4 4.3 350 UVLO Hysteresis [V] 4.2 300 4.0 3.9 3.8 3.7 3.6 -25 0 25 50 75 100 125 Ist [μA] 4.1 250 200 150 -25 0 25 50 75 100 125 Temperature [°C] Temperature [°C] Figure 6. UVLO Hysteresis vs. Temp. Figure 7. Start-up Supply Current vs. Temp. 1.5 1.4 1.3 1.3 1.2 Iop [mA] Istr [mA] 0 25 50 75 100 125 1.2 1.1 1.0 0.9 0.8 -25 1.1 1.0 0.9 0.8 -25 0 25 50 75 100 125 Temperature [°C] Temperature [°C] Figure 8. Operating Supply Current vs. Temp. Figure 9. VSTR Star-up Current vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 6 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Typical Performance Characteristics (Continued) 1.10 1.05 CSFB2 CSFB3 70 68 CS/FB Threshold [V] 1.00 0.95 0.90 0.85 0.80 0.75 0.70 -25 0 25 50 75 100 125 Fosc [kHz] 66 64 62 60 -25 0 25 50 75 100 125 Temperature [°C] Temperature [°C] Figure 10. Burst On/Off Voltage vs. Temp. Figure 11. Operating Frequency vs. Temp. 0.20 0.18 0.16 0.14 0.12 0.10 -25 80 78 Dmax [%] 0 25 50 75 100 125 Kplimit 76 74 72 70 -25 0 25 50 75 100 125 Temperature [°C] Temperature [°C] Figure 12. Offset Gain vs. Temp. Figure 13. Maximum Duty Cycle vs. Temp. 20.0 19.6 19.2 18.8 18.4 18.0 -25 4.4 4.2 VLATCH [V] 0 25 50 75 100 125 VOVP [V] 4.0 3.8 3.6 -25 0 25 50 75 100 125 Temperature [°C] Temperature [°C] Figure 14. OVP Voltage vs. Temp. Figure 15. Latch Voltage vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 7 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Typical Performance Characteristics (Continued) 2.10 1.70 1.65 2.05 VLUVPoff [V] VLUVPon [V] 0 25 50 75 100 125 1.60 1.55 1.50 2.00 1.95 1.45 1.90 -25 1.40 -25 0 25 50 75 100 125 Temperature [°C] Temperature [°C] Figure 16. LUVP On-to-Off Voltage vs. Temp. Figure 17. LUVP Off-to-On Voltage vs. Temp. CSFB1 Threshold voltage [V] 1.08 1.04 1.00 0.96 0.92 -25 0 25 50 75 100 125 Temperature [°C] Figure 18. CS/FB Threshold Voltage vs. Temp. © 2007 Fairchild Semiconductor Corporation FAN7602B Rev. 1.0.0 8 www.fairchildsemi.com FAN7602B — Green Current-Mode PWM Controller Applications Information 1. Start-up Circuit and Soft Start Block The FAN7602B contains a start-up switch to reduce the power loss of the external