L6565 STMicroelectronics, L6565 Datasheet
L6565
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L6565 Summary of contents
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... R2 2.1V 1.6V January 2003 QUASI-RESONANT SMPS CONTROLLER DESCRIPTION The L6565 is a current-mode primary controller IC, specifically designed to build offline Quasi-resonant ZVS (Zero Voltage Switching at switch turn-on) fly- back converters. Quasi-resonant operation is achieved by means of a transformer demagnetization sensing input that trig- gers MOSFET's turn-on. ...
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... L6565 DESCRIPTION (continued) Converter's power capability variations with the mains voltage are compensated by line voltage feedforward. At light load the device features a special function that automatically lowers the operating frequency still main- taining the operation as close to ZVS as possible. In addition to very low start-up and quiescent currents, this feature helps keep low the consumption from the mains at light load and be Blue Angel and Energy Star com- pliant ...
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... Value 30 700 -0 (source) -10 (sink) (Minidip) 1 0.65 (SO8) -40 to 150 -55 to 150 Min. Typ. Max. 10.3 12.5 13.5 14.5 8.7 9.5 10.3 3. 2.3 3.5 1 2.465 2.5 2.535 2.44 2.56 2 -0.1 L6565 Unit °C/W Unit °C °C Unit 4 µA 3 3 µ µA 3/17 ...
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... L6565 ELECTRICAL CHARACTERISTCS (continued -25 to 125° 12V Symbol Parameter G Voltage Gain V GB Gain-Bandwidth Product I Source Current COMP Sink Current V Upper Clamp Voltage COMP Lower Clamp Voltage CURRENT SENSE COMPARATOR I Input Bias Current CS t Delay to Output d(H-L) V Current Sense Reference Clamp ...
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... Figure 5. Pin 2 (COMP) V-I characteristics V [V] COMP 100 125 Figure 6. ZCD blanking time vs. COMP voltage D94IN048A T BLANK (°C) 100 = 2.5V 0.5 1 1.5 2 2.5 V [V] VFF °C Vpin1 = 0 Regulation range [mA] COMP [µ ° [V] COMP L6565 3 3 5/17 ...
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... L6565 Figure 7. Gate-drive output saturation V [V] pin7 2 °C Vcc = 14.5 V SINK 2 1 100 200 300 I [mA] GD Figure 8. Gate-drive output saturation V [V] pin7 0 Vcc - 0.5 Vcc - 0.5 -0.5 Vcc - 1.0 -1 Vcc - 1.5 -1.5 Vcc - 2.0 -2 Vcc - 0.5 -2.5 0 100 200 I [mA] GD Figure 9. IC consumption vs. temperature Icc [mA 0.5 0.2 0.1 0.05 0.02 - [°C] 6/17 Figure 10 ...
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... Quasi-resonant operation in offline flyback converters lies in synchronizing MOSFET's turn-on to the transform- er's demagnetization. Detecting the resulting negative-going edge of the voltage across any winding of the transformer can do this. The L6565 is provided with a dedicated pin that allows doing the job with a very simple interface, just one resistor. ...
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... ZCD circuit erroneously; second, to realize the Frequency Foldback function (see the relevant description). Figure 13. Zero Current Detection and Triggering Block; Disable and Frequency Foldback Blocks L6565 +Vin R ZCD ...
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... L6565 puts a limit on the minimum OFF-time of the switch. This is done by blanking the triggering block of the ZCD circuit as mentioned before. The duration of the blanking time (3.5µs min function of the error amplifier output VCOMP, as shown in the diagram of figure 6. If the load current and the input voltage are such that the switch OFF-time falls below the minimum blanking time of 3.5µ ...
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... R1 R2 COMP 2 INV 1 - E/A + 2.5V 10/17 , that is on the overcurrent setpoint, so that function csx V = Upper clamp COMP 0 [V] VFF VFF CS ZCD STARTER ZCD VOLTAGE + FEED PWM - FORWARD + Hiccup 2.5 3 3.5 Rs starter STOP DRIVER GD R (reset-dominant) DISABLE L6565 ...
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... GD) from being pulled too negative. An internal pull-down circuit holds the output low when the device is in UVLO conditions, to ensure that the ex- ternal MOSFET cannot be turned on accidentally (e.g. at power-on). Figure 18. Gate driver with UVLO pull-down Vcc 8 L6565 7 DRIVER UVLO 6 GND GD Q L6565 11/17 ...
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... N1 (24T+24T series connected), 2xAWG28 ( N2 AWG28 N3 AWG28 Naux AWG32 ( Figure 20. 40W Wide Range Mains SMPS for inkjet printer 2A fuse 16R 1nF Vin 88 to 100nF 100nF 264 Vac 15mH L6565 PC817 3.3 nF 12/17 C6 4700pF/ 4KV D1 1N4148 B1 2KBP04M ...
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... APPLICATION IDEAS Here follows a series of ideas/suggestions aimed at either improving performance or solving common applica- tion issues of L6565-based power supplies. Figure 21. Enhanced turn-off for big MOSFET's drive Figure 22. Latched shutdown on: a) feedback disconnection; b) overload or short circuit BC327 a) Figure 23. Secondary Feedback loop configurations Vcc ...
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... BC327 1N4148 470 pF 2.7 k RELATED DOCUMENTATION [1] "L6565, QUASI-RESONANT CONTROLLER” (AN1326) [2] “25W QUASI-RESONANT FLYBACK CONVERTER FOR SET-TOP BOX APPLICATIONS USING THE L6565” (AN1376) [3] “EVAL6565N, 30W AC-DC ADAPTER WITH THE L6565 QUASI-RESONANT PWM CONTROLLER” (AN1439). 14/17 Vcc VFF E/A block ...
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... DIM. MIN. TYP. MAX. MIN. A 3.32 a1 0.51 0.020 B 1.15 1.65 0.045 b 0.356 0.55 0.014 b1 0.204 0.304 0.008 D 10.92 E 7.95 9.75 0.313 e 2.54 e3 7.62 e4 7.62 F 6.6 I 5.08 L 3.18 3.81 0.125 Z 1.52 inch TYP. MAX. 0.131 0.065 0.022 0.012 0.430 0.384 0.100 0.300 0.300 0.260 0.200 0.150 0.060 OUTLINE AND MECHANICAL DATA Minidip L6565 15/17 ...
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... L6565 mm DIM. MIN. TYP. MAX. A 1.75 a1 0.1 0.25 0.004 a2 1.65 a3 0.65 0.85 0.026 b 0.35 0.48 0.014 b1 0.19 0.25 0.007 C 0.25 0.5 0.010 c1 45 (typ.) D (1) 4.8 5.0 0.189 E 5.8 6.2 0.228 e 1.27 e3 3.81 F (1) 3.8 4.0 L 0.4 1.27 0.016 M 0 (max.) (1) D and F do not include mold flash or protrusions. Mold flash or potrusions shall not exceed 0.15mm (.006inch). 16/17 inch MIN. TYP. ...
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... The ST logo is a registered trademark of STMicroelectronics Australia - Brazil - Canada - China - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan -Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States. © 2003 STMicroelectronics - All Rights Reserved STMicroelectronics GROUP OF COMPANIES http://www.st.com L6565 17/17 ...