Transcript Slide 1
Fairchild Power Switch(FPS) TV Solution Power Conversion www.fairchildsemi.com Features and Advantages of FSCQ-series Features • • • • Optimized for Quasi-resonant converter (Low EMI and High Efficiency) Fully avalanche rated and 100% tested SenseFET Pulse-by-pulse current limiting Improved reliability through various protection functions Over voltage, Over load, Over current, Thermal shutdown • • • • Advanced Burst operation for low power consumption in standby (<1W) Internal Soft start function (20ms) Extended Quasi-resonant operation for wide operation range Reduced startup and operating currents Advantages • Reduced board space (simple & compact circuit design) • Decreased assembly time and field failure rate Enhanced productivity 2 FSCQ-series Functional Block Diagram QRC Control Sync 5 Vcc 3 Drain 1 + Threshold Quasi-resonant (QR) switching controller - + fs - Burst Mode Operation 9V/15V Soft start 4.6V/2.6V : Normal QR 3.0V/1.8V : Extended QR Burst mode Controller VBurst Normal operation Vref Ibufb IFB Main bias Normal operation Vref Internal bias Ib Idelay FB Auxiliary Vref OSC Burst Switching Vref Vcc Vcc good SenseFET PWM 4 2.5R OLP S Q R Q Gate driver R LEB 600ns Current Mode Control VSD Sync S Vovp Vcc good AOCP Q AOCP Q R S Q 2 GND TSD OVP Q R Auto Restart Mode TSD Power Reset Latch Mode 3 Vocp FPS lineup for CRT-TV application Function Device Vdmax (V) Ipeak (A) Po(max)(1) 85-265VAC Protection Option PKG Fopr (KHz) Rds(on) Max () OLP OCL OVP TSD High Power Quasi-Resonant Converter Applications Color TV KA5Q0565RT 650 3.5 60 QRC 2.2 YES YES YES YES TO-220F-5L KA5Q0740RT 400 5.0 85 QRC 1.1 YES YES YES YES TO-220F-5L KA5Q0765RTH 650 5.0 85 QRC 1.6 YES YES YES YES TO-220F-5L KA5Q12656RTH 650 6.0 140 QRC 0.9 YES YES YES YES TO-220F-5L KA5Q1265RFH 650 8.0 160 QRC 0.9 YES YES YES YES TO-3PF-5L KA5Q1565RF 650 11.5 210 QRC 0.65 YES YES YES YES TO-3PF-5L FSCQ0565RT 650 3.5 60 QRC 2.2 YES YES YES YES TO-220F-5L FSCQ0765RT 650 5.0 85 QRC 2.0 YES YES YES YES TO-220F-5L FSCQ0965RT 650 6.0 110 QRC 1.6 YES YES YES YES TO-220F-5L FSCQ1265RT 650 7.0 140 QRC 0.9 YES YES YES YES TO-220F-5L FSCQ1465RT 650 8.0 160 QRC 0.70 YES YES YES YES TO-220F-5L FSCQ1565RT 650 8.0 170 QRC 0.65 YES YES YES YES TO-220F-5L FSCQ1565RP 650 11.5 210 QRC 0.65 YES YES YES YES TO-3PF-7L 4 KA5Q series V.S FSCQ-series Generation KA5Q-Series FSCQ-Series FSCQ Advantages Control Method QRC/PSR High Efficiency/Low EMI QRC with high frequency limit High Efficiency/Low EMI Temp. of device can be lower at high line input Start-up current /Operation current Max. 200uA / 18mA(always constant) Max. 50uA / 6mA(reduced in burst mode) Lower standby power Output regulation in standby By Vcc control By Feedback control Just difference of method Output voltage drop in standby About half Any level Lower standby power but MCU reset must be considered Standby power Under 2W Under 1W Soft start None 20mS SenseFET Q-FET S-FET PKG TO220F-5L/TO3PF-5L TO220F-5L/TO3PF-7L 5 Reducing stress on Power MOSFET & transformer Same PCB pattern can be used for different PKG Power Consumptions in standby mode 6 Typical Application circuit T1 EER3540 RT101 5D-9 BD101 R101 120kΩ 0.25W D104 UF4007 1 ZD101 18V 1W 3 11 4 13 BEAD101 R102 120kΩ 0.25W Drain SYNC 3 Vcc IC101 5 FSCQ0765RT GND 2 C103 10uF 50V FB 4 C106 47nF 50V R106 C104 1kΩ 10uF 1W 50V D102 1N4937 12V, 1A 10 1 C102 220uF 400V D205 EGP20D C107 1nF 1kV 12 C204 1000uF 35V C210 470pF 1kV D204 EGP20D 18V, 0.5A C205 1000uF 35V C209 470pF 1kV D202 EGP20J D103 1N4148 R105 470Ω 0.25W R104 D101 R103 6 1.5kΩ 1N4937 5.1Ω 0.25W 0.25W 14 15 16 C105 3.9nF 50V C201 100uF 160V C207 470pF 1kV 125V, 0.4A L201 BEAD C202 47uF 160V D203 EGP20D 24V, 0.5A 17 7 LF101 18 OPTO101 817A C203 1000uF 35V C208 470pF 1kV VR201 30kΩ R205 220kΩ 0.25W R201 1kΩ 0.25W FUSE 250V 3.0A C206 22nF 50V C301 2.2nF Q201 KA431 7 Normal ZD202 5.1V 0.5W R202 1kΩ 0.25W C101 330nF 275VAC R208 1kΩ 0.25W R203 39kΩ 0.25W R204 4.7kΩ 0.25W D201 Q202 KSC945 SW 201 R207 5.1kΩ 0.25W R206 5.1kΩ 0.25W Standby Normal Quasi-Resonant Switching Advantages - Reduced switching noise (Low EMI) - Improved efficiency - Removed RCD snubber 8 Normal Quasi-Resonant Switching Limitations - Intermittent switching at light load due to a relatively large LEB time Increased switching loss at light load Switching frequency Vds Light load Ids Vds Heavy load Ids Output power 9 Extended Quasi-Resonant Switching Switching frequency Extended QR Switching 90kHz Normal QR Switching 45kHz Output power Advantages - Guarantee stable operation over wide load range - Improve efficiency at light load condition 10 Internal Soft-start 85V input 265V input • Internal soft start (20ms) • For a fast output build up, offset is introduced in the soft start 11 Over load Protection - Output short 85V input 265V input 12 Abnormal over current protection – Diode short 85V input 265V input 13 Over voltage protection -Feedback open 85V input 265V input 14 Burst operation - basic features Vo2 Vo2_min - Drop output voltage to below half (any level) to minimize the loss caused by leakage current in the high voltage output - Reduce the effective switching frequency to minimize switching loss - Reduce the FPS operating current in the burst operation Vfb 0.4V Iop 4mA 250uA Vds Picture On Picture Off Picture On Burst Mode 15 Burst operation - Output drop circuit VO2 Linear Regulator VO1 (B+) RD R1 C KA431 A - Normal mode : Vo1 (B+) is regulated - Standby mode : Vo2 is regulated Dz Rbias CF Micom RF D1 R3 Q1 Picture ON R R2 16 Burst operation waveforms Normal Standby Standby Normal 17 Burst operation waveforms Vi=85Vac Vi=265Vac 1. Vds 2. Vcc 3. Vfb 4. Id 18