VIPER15LD STMicroelectronics, VIPER15LD Datasheet
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VIPER15LD
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VIPER15LD Summary of contents
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... SMPS for set-top boxes, DVD players and recorders, white goods Table 1. Device summary Order codes VIPER15LN / VIPER15HN VIPER15HD / VIPER15LD VIPER15HDTR / VIPER15LDTR August 2010 Off-line high voltage converters SO16 narrow SO-16 Description The device is an off-line converter with an 800 V rugged power section, a PWM control, double ...
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Contents Contents 1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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VIPER15 8 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Block diagram 1 Block diagram Figure 2. Block diagram 2 Typical power Table 2. Typical power Part number VIPER15 1. Typical continuous power in non ventilated enclosed adapter measured at 50 °C ambient. 2. Maximum practical continuous power in an ...
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VIPER15 3 Pin settings Figure 3. Connection diagram (top view) Note: The copper area for heat dissipation has to be designed under the DRAIN pins. Table 3. Pin description Pin n. Name DIP-7 SO16 1 1...2 GND - 4 N.A. ...
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Electrical data 4 Electrical data 4.1 Maximum ratings Table 4. Absolute maximum ratings Pin Symbol (DIP7 DRAIN DRAIN V 3 ZCD ...
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VIPER15 4.3 Electrical characteristics (T = -25 to 125 ° Table 6. Power section Symbol V Break-down voltage BVDSS I OFF state drain current OFF Drain-source on state R DS(on) resistance Effective (energy related) C OSS output capacitance ...
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Electrical data Table 8. Controller section Symbol Feedback pin V Overload shutdown threshold FBolp V Linear dynamics upper limit FBlin V Burst mode threshold FBbm V Burst mode hysteresis FBbmhys I Feedback sourced current FB R Dynamic resistance FB(DYN) ΔV ...
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VIPER15 Table 8. Controller section (continued) Symbol Oscillator section Internal frequency limit F OSClim Internal frequency limit F Starter frequency STARTER F OSCmin Brown-out protection V Brown-out threshold BRth Voltage hysteresis above V BRhyst V BRth I Current hysteresis BRhyst ...
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Electrical data Figure 4. Minimum turn-on time test circuit 14 V Figure 5. Brown-out threshold test circuits 14 V Figure 6. OVP threshold test circuits 14 V Note: Adjust V above V DD 10/40 GND DRAIN VDD DRAIN 50 Ω ...
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VIPER15 5 Typical electrical characteristics Figure 7. Current limit vs T Figure 9. HFB vs T Figure 11. Brown-out hysteresis vs T Figure 8. J Figure 10. Brown-out threshold Figure 12. Brown-out hysteresis current J Doc ID ...
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Typical electrical characteristics Figure 13. Operating supply current (no switching Figure 15. V ZCD V (mV) ZCD 500 450 400 350 300 0.0 50.0 Figure 17. Power MOSFET on-resistance vs T 12/40 Figure 14. Operating supply current J ...
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VIPER15 Figure 19. Thermal shutdown DDon V DDoff V DD(RESTART) I DRAIN HYST SD Normal operation Typical electrical characteristics Shut down after over temperature Doc ID 15455 Rev 5 time ...
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Typical circuits 6 Typical circuits Figure 20. Min-features QR flyback application Figure 21. Full-features QR flyback application 14/40 Doc ID 15455 Rev 5 VIPER15 ...
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VIPER15 7 Operation description VIPER15 is a high-performance low-voltage PWM controller IC with an 800 V, avalanche rugged power section. The controller includes the current-mode PWM logic and the ZCD (zero current detect) circuit for QR operation, the start-up circuitry ...
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Operation description 7.3 Power-up description If the input voltage rises up till the device start level, V grow due to the I DDch start-up circuit. If the V power MOSFET starts switching and the HV current generator is turned OFF, ...
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VIPER15 As soon as the output voltage reaches the regulated value, the regulation loop takes over and the drain current is regulated below its limit value lower than the threshold V Figure 22. I current during start-up ...
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Operation description Figure 24. Timing diagram: Start-up phase and soft start (case DRAIN t I Dlim FBolp V FBlin V OUT Regulated value Figure 25. Timing diagram: Start-up phase and soft start (case ...
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VIPER15 7.4 Power-down description At converter power-down, the system loses regulation as soon as the input voltage is so low that the peak current limitation is reached. The V the V threshold the power MOSFET is switched OFF, the energy ...
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Operation description 7.6 Quasi-resonant operation The control core of the VIPER15 is a current-mode PWM controller with a the zero current detection circuit designed for Quasi-Resonant (QR) operation, a technique that provides the benefits of minimum turn-on losses, low EMI ...
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VIPER15 Figure 27. Switching frequency vs output load Figure 28. Zero current detection circuit and oscillator circuit Doc ID 15455 Rev 5 Operation description 21/40 ...
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Operation description 7.7 Frequency foldback function and valley skipping mode The switching frequency, in Quasi Resonant mode, is not fixed and it depends on both the load and the converter’s input voltage. The switching frequency increases when the load decreases, ...
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VIPER15 7.8 Double blanking time The blanking time, T value) and the higher one is 6,3 μs (typical value). The value is linked to the voltage V sampled during the time T Section 7.11 on page 26 has the higher ...
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Operation description 7.9 Starter If the amplitude of the voltage on ZCD pin at the end of one oscillator cycle is smaller than the V arming threshold, in which case MOSFET's turn-ON could not be triggered, the ZCDAth system would ...
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VIPER15 Figure 31. Typical power capability vs input voltage in quasi-resonant converter’s In order to proper select the value of the resistance R are known the proper I voltage. The following approximated formula calculates the value of the resistor R ...
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Operation description Figure 32. ZCD pin typical external configuration 7.11 Overvoltage protection (OVP) The VIPER15 has integrated the logic for the monitor of the output voltage using as input signal the voltage V the voltage from the auxiliary winding tracks ...
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VIPER15 Equation 6 Where: ● the OVP threshold (see OVP ● the converter output voltage value to activate the OVP (set by designer) OUT OVP designer ● the auxiliary winding turns AUX ● N ...
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Operation description 7.12 Summary on ZCD pin Referring to the Figure 32 on page 26 implement the following functions: 1. Current limit Line feed-forward compensation 3. Output overvoltage protection (OVP) 4. Zero current detection for QR operation Chosen ...
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VIPER15 The time, from the high load detection, V depends from the value of the capacitor C OLP delay time can be calculating by the formula: Equation 8 The current, I FB, also a part of the compensation loop , ...
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Operation description Equation 11 The R is the dynamic resistance seen by the FB pin and reported on FB(DYN) page 8. The C capacitor fixes the OLP delay and usually C FB1 Equation 8 on page 29 considered instead of ...
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VIPER15 Figure 36. Timing diagram: Overload protection I OUT V OUT I DRAIN I Dlim FBolp V FBlin SOFT START OVER LOAD Warning START UP Doc ID 15455 Rev 5 Operation description OVER ...
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Operation description 7.14 Burst-mode operation at no load or very light load When the load decrease the feedback loop reacts lowering the feedback pin voltage falls down the burst mode threshold, V switched on. After the MOSFET stops, ...
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VIPER15 Figure 38. Brown-out protection: BR external setting and timing diagram VDD V IN_DC BRhyst Fixed the V and the V INon can be established for the calculation of the resistors R Equation ...
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Operation description nd 7.16 2 level overcurrent protection and hiccup mode The is protected against short-circuit of the secondary rectifier, short-circuit on the VIPER15 secondary winding or a hard-saturation of fly-back transformer. Such as anomalous condition is invoked when the ...
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VIPER15 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 Figure 40. DIP-7 package dimensions 36/ Doc ID 15455 Rev 5 VIPER15 ...
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VIPER15 Table 11. SO16 narrow mechanical data Dim ccc Databook (mm.) Min. Typ. 0.1 1.25 0.31 0.17 9.8 9.9 5.8 6 3.8 3.9 1.27 0.25 0.4 0 Doc ...
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Package mechanical data Figure 41. SO16 package dimensions 38/40 Doc ID 15455 Rev 5 VIPER15 ...
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VIPER15 9 Revision history Table 12. Document revision history Date 05-Mar-2009 07-Apr-2009 20-Jul-2009 26-Aug-2009 27-Aug-2010 Revision 1 Initial release Updated Table 3 , Table 6 2 Figure 21 Updated application paragraph in coverpage and 3 page 8 4 Content reworked ...
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