* Dramatically Simplifi es CV Converters > ΕՕՕՕՕՕՕՕՕ Օ Eliminates optocoupler and all secondary CV control circuitry Eliminates bias winding supply Ֆ IC is self biasing Advanced Performance Features Compensates for external component temperature variationsVery tight IC parameter tolerances using proprietary trimming technology Continuous and/or discontinuous mode operation for design fl exibilityFrequency jittering greatly reduces EMI fi lter costEven tighter output tolerances achievable with external resistor selection/trimming Advanced Protection/Safety Features EcoSmart Auto-restart protection reduces delivered power by >95% for output short circuit and all control loop faults (open and shorted components) Hysteretic thermal shutdown automatic recovery reduces power supply returns from the fi eld Meets HV creepage requirements between Drain and all other pins, both on the PCB and at the package > Wide RangeHV DC Input DS FBBP LinkSwitch-CV PI-5195-080808 (a) Typical Application Schematic (b) Output Characteristic V O ֱ5% Auto-Restart Ζ Energy Effi cient > PI-5196-080408 I O No-load consumption <200 mW at 230 VAC and down to below 70 mW with optional external bias Easily meets all global energy effi ciency regulations with no added components ON/OFF control provides constant effi ciency down to very light loads ideal for mandatory EISA and ENERGY STAR 2.0 regulationsNo primary or secondary current sense resistors ֖ maximizes effi ciency > Figure 1. Typical Application Schematic (a) and Output Characteristic Envelope (b). Green Package Halogen free and RoHS compliant package > *Optional with LNK623-624PG/DG. (see Key Application Considerations section for clamp and other external circuit design considerations). Applications Output Power Table DVD/STBAdaptersStandby and auxiliary supplies Home appliances, white goods and consumer electronics Industrial controls > 230 VAC 15%85-265 VAC Product 3 Peak or Open Frame Peak or Open Frame Adapter 1 1 2 Adapter 2 LNK623PG/DG 6.5 W9 W5.0 W6 W LNK624PG/DG 7 W11 W5.5 W6.5 W LNK625PG/DG 8 W13.5 W6.5 W8 W LNK626PG 10.5 W17 W8.5 W10 W Table 1. Output Power Table. Based on 5 V Output. Notes: 1. Minimum continuous power in a typical non-ventilated enclosed adapter measured at +50 ѰC ambient. 2. Maximum practical continuous power in an open frame design with adequate heatsinking, measured at 50 C ambient (see Key Application Considerations section for more information). 3. Packages: P: DIP-8C, D: SO-8C. The LinkSwitch-CV dramatically simplifies low power, constant voltage (CV) converter design through a revolutionary control technique which eliminates the need for both an optocoupler and secondary CV control circuitry while providing very tight output voltage regulation. The combination of proprietary IC trimming and E-ShieldЙ transformer construction techniques enables Clampless designs with the LinkSwitch-CV LNK623/4. LinkSwitch-CV provides excellent cross-regulation for multiple-output flyback applications such as DVDs and STBs. A 700 V power MOSFET and ON/OFF control state machine, self-biasing, frequency jittering, cycle-by-cycle current limit, and hysteretic thermal shutdown circuitry are all incorporated onto one IC. > www.powerint.com December 2008 size="-1">

s), whilst keeping the disable period of 2.5 seconds. This effectively reduces the Auto-Restart duty cycle to less than 0.01%. > Constant Voltage (CV) Operation > The controller regulates the feedback pin voltage to remain at V Over-Temperature Protection The thermal shutdown circuitry senses the die temperature. The threshold is set at 142 C typical with a 60 аC hysteresis. When the die temperature rises above this threshold (142 C) the power MOSFET is disabled and remains disabled until the die temperature falls by 60 аC, at which point the MOSFET is re-enabled. The LinkSwitch-CV combines a...

Single Point Grounding Use a single point (Kelvin) connection at the negative terminal of the input fi lter capacitor for the LinkSwitch-CV SOURCE pin and bias winding return. This improves surge capabilities by returning surge currents from the bias winding directly to the input fi lter capacitor. Bypass Capacitor The BYPASS pin capacitor should be located as close as possible to the SOURCE and BYPASS pins. Feedback Resistors Place the feedback resistors directly at the FEEDBACK pin of the LinkSwitch-CV device. This minimizes noise coupling. Thermal Considerations The copper area connected to...

B+ PRI RTN CLAMP > DS FBBP IsourceTraceimpedance Bias winding currents flow in signal source tracesVoltage drops across trace impedance may cause degraded performance Power currentsflow in signal source traceLine surgecurrents can flow through device Drain trace in closeproximity of feedback tracewill couple noise intofeedback signal $ V > S PI-5267-111008 Figure 8. Schematic Representation of Electrical Impact of Improper Layout. >

R R > C2 C2 C > C1 C > C1 D > C2 R > C1 R > C1 D > C1 D > C1 PI-5107-110308 PI-5108-110308 Figure 9. RCD Clamp, Low Power or Low Leakage Inductance Designs. RCD Clamp With Zener Bleed. High Power or High Leakage Inductance Designs. > Black Trace: D > C1 is a FR107 (fast type, trr = 500 ns)Gray Trace: D > C1 is a 1N4007G (standard recovery, trr = 2 us) Figure 10. Clamp Circuit (top). Feedback Pin Voltage (bottom). >

Figure 12. RC Network Across R > BOTTOM (R6) to Reduce Pulse Grouping. Top Trace: Drain Waveform (200 V/div)Bottom Trace: Output Ripple Voltage (50 mV/div)Split Screen with Bottom Screen ZoomTop Trace: Drain Waveform (200 V/div) Bottom Trace: Output Ripple Voltage (50 mV/div) Top Trace: Drain Waveform (200 V/div)Bottom Trace: Output Ripple Voltage (50 mV/div)Split Screen with Bottom Screen ZoomTop Trace: Drain Waveform (200 V/div) Bottom Trace: Output Ripple Voltage (50 mV/div) Figure 11. Not Pulse Grouping (<5 Consecutive Switching Cycles). Pulse Grouping (>5 Consecutive Switching Cycles). >