EVAL6599-200W STMicroelectronics, EVAL6599-200W Datasheet

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Features ■ duty cycle, variable frequency control of resonant half-bridge ■ High-accuracy oscillator ■ 500 kHz operating frequency ■ Two-level OCP: frequency-shift and latched shutdown ■ Interface with PFC controller ■ Latched disable input ■ Burst-mode ...

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Contents Contents 1 Device description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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L6599 1 Device description The L6599 is a double-ended controller specific for the resonant half-bridge topology. It provides 50 % complementary duty cycle: the high-side switch and the low-side switch are driven ON\OFF 180° out-of-phase for exactly the same time. ...

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Pin settings 2 Pin settings 2.1 Connection Figure 2. Pin connection (top view) 2.2 Functions Table 2. Pin functions N. Name Soft start. This pin connects an external capacitor to GND and a resistor to RFmin (pin 4) that set ...

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L6599 Table 2. Pin functions (continued) N. Name Minimum oscillator frequency setting. This pin provides a precise 2 V reference and a resistor connected from this pin to GND defines a current that is used to set the minimum oscillator ...

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Typical system block diagram Table 2. Pin functions (continued) N. Name Low-side gate-drive output. The driver is capable of 0.3 A min. source and 0.8 A min. sink 11 LVG peak current to drive the lower MOSFET of the half-bridge ...

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L6599 4 Electrical data 4.1 Maximum ratings Table 3. Absolute maximum ratings Symbol Pin V 16 BOOT V 14 OUT 14 dV /dt OUT PFC_STOP I 9 PFC_STOP V 7 LINEmax I 4 RFmin 1 ...

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Electrical characteristics 5 Electrical characteristics 105 ° kΩ; unless otherwise specified. RFmin Table 5. Electrical characteristics Symbol IC supply voltage V Operating range CC V Turn-ON threshold CC(ON) V Turn-OFF threshold ...

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L6599 Table 5. Electrical characteristics (continued) Symbol Line sensing V Threshold voltage th I Current hysteresis Hyst V Clamp level clamp DIS function I Input bias current DIS V Disable threshold th Oscillator D Output duty cycle f Oscillation frequency ...

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Electrical characteristics Table 5. Electrical characteristics (continued) Symbol Delayed shutdown function I Open-state current leak I Charge current CHARGE Threshold for forced Vth 1 operation at max. frequency Vth Shutdown threshold 2 Vth Restart threshold 3 Low - side gate ...

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L6599 6 Typical electrical performance Figure 4. Device consumption vs supply voltage Figure 6. V clamp voltage vs CC junction temperature Typical electrical performance Figure 5. IC consumption vs junction temperature Figure 7. UVLO thresholds vs junction temperature 11/36 ...

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Typical electrical performance Figure 8. Oscillator frequency vs junction temperature Figure 10. Oscillator frequency vs timing components 12/36 Figure 9. Dead-time vs junction temperature Figure 11. Oscillator ramp vs junction temperature L6599 ...

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L6599 Figure 12. Reference voltage vs junction temperature Figure 14. OCP delay source current vs junction temperature Typical electrical performance Figure 13. Current mirroring ratio vs junction temperature Figure 15. OCP delay thresholds vs junction temperature 13/36 ...

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Typical electrical performance Figure 16. Standby thresholds vs junction temperature Figure 18. Line thresholds vs junction temperature Figure 20. Latched disable threshold vs junction temperature 14/36 Figure 17. Current sense thresholds vs junction temperature Figure 19. Line source current vs ...

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L6599 7 Application information The L6599 is an advanced double-ended controller specific for resonant half-bridge topology. In these converters the switches (MOSFETs) of the half-bridge leg are alternately switched on and OFF (180° out-of-phase) for exactly the same time. This ...

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Application information 7.1 Oscillator The oscillator is programmed externally by means of a capacitor (CF), connected from pin 3 (CF) to ground, that will be alternately charged and discharged by the current defined with the network connected to pin 4 ...

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L6599 After fixing CF in the hundred the nF (consistently with the maximum source capability of the RF the value of RF min cover the entire range needed for regulation, from the minimum value f voltage and ...

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Application information 7.2 Operation at no load or very light load When the resonant half-bridge is lightly loaded or unloaded at all, its switching frequency will be at its maximum value. To keep the output voltage under control in these ...

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L6599 Essentially, RF max burst-mode operation. Once fixed f Note that, unlike the associated to some load Pout max the transformer's peak currents are low enough not to cause audible noise. Resonant converter's switching frequency, however, depends ...

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Application information Figure 26. Load-dependent operating modes: timing diagram STBY 1.25V f osc LVG HVG PFC_STOP PFC GATE-DRIVE Figure 27. How the L6599 can switch OFF a PFC controller at light load Vcc 12 L6599 9 20/36 Resonant Mode Burst-mode ...

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L6599 7.3 Soft-start Generally speaking, purpose of soft-start is to progressively increase converter's power capability when it is started up avoid excessive inrush current. In resonant converters the deliverable power depends inversely on frequency, then soft- start ...

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Application information Figure 29. Power vs frequency curve in an resonant half-bridge As a result, the average input current will smoothly increase, without the peaking that occurs with linear frequency sweep, and the output voltage will reach the regulated value ...

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L6599 7.4 Current sense, OCP and OLP The resonant half-bridge is essentially voltage-mode controlled; hence a current sense input will only serve as an overcurrent protection (OCP). Unlike PWM-controlled converters, where energy flow is controlled by the duty cycle of ...

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Application information Figure 31. Lossless current sensing technique, with capacitive shunt pk The device is equipped with a current sensing input (pin 6, ISEN) and a sophisticated overcurrent management system. The ISEN pin is internally connected to the input of ...

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L6599 The circuit shown in is small (not above some hundred Ω, just to limit current spiking) the circuit series operates like a capacitive current divider; C less and will be a low-loss type, the sense resistor ...

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Application information Figure 32. Soft-start and delayed shutdown upon overcurrent timing diagram Vcc T Css 2V Primary Current 0A ISEN 0.8V 3.5V DELAY 2V 0.3V Vout PFC_STOP START-UP SOFT-START This function is realized with pin 2 (DELAY), by means of ...

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L6599 The timing diagram of Note that if during T threshold the IC keeps memory of the event and will not restart immediately after V exceeds the start-up threshold if V(DELAY) is still higher than 0.3 V. Also the PFC_STOP ...

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Application information Figure 33. Line sensing function: internal block diagram and timing diagram With reference to (Vin ) and OFF (Vin ON which, solved for R While the line undervoltage is active there is no PWM activity, thus the V ...

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L6599 voltage on the pin exceeds 7 V the device is shutdown. If its supply voltage is always above the UVLO threshold, the IC will restart as the voltage falls below 7 V. The LINE pin, while the device is ...

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Application information This concern applies to converters designed with a high resonance frequency (indicatively, > 150 kHz), so that they run at high frequency also at full load. Otherwise, the converter will run at high frequency only at light load, ...

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... L6599 7.8 Application example Figure 35. EVAL6599-90W demo board, 90W adapter with L6563 and L6599: electrical schematic Application information 31/36 ...

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... Application information Table 6. EVAL6599-90W demo board, 90W adapter with L6563 & L6599: evaluation data Vin = 115 Vac Vout Iout [V] [A] 18.95 4.71 18.95 3.72 18.97 2.7 18.98 1.71 18.99 1.0 18.99 0.5 19.00 0.25 19.01 0.080 19.01 0.053 19.01 0.027 19.01 ...

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L6599 8 Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at: www.st.com. ...

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Package mechanical data Table 8. SO16N mechanical data Dim ( ( Figure 37. Package dimensions 34/36 mm. Min Typ Max 1.75 0.1 0.25 1.6 ...

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L6599 9 Revision history Table 9. Document revision history Date 15-May-2006 18-Jul-2006 11-Feb-2009 Revision 1 Initial release 2 Typo in cover page Not recommended for new designs, the device has been 3 replaced by L6599A Revision history Changes 35/36 ...

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