VIPER12ASTR-E STMicroelectronics, VIPER12ASTR-E Datasheet
VIPER12ASTR-E
Specifications of VIPER12ASTR-E
VIPER12ASTR-E
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VIPER12ASTR-E Summary of contents
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Low power offline switched-mode power supply primary switcher Features ■ Fixed 60 kHz switching frequency ■ wide range V DD ■ Current mode control ■ Auxiliary undervoltage lockout with hysteresis ■ High voltage start-up current ...
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Contents Contents 1 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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VIPER12A-E 1 Electrical data 1.1 Maximum rating Stressing the device above the rating listed in the “absolute maximum ratings” table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or ...
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Electrical characteristics 2 Electrical characteristics ° unless otherwise specified J DD Table 3. Power section Symbol Parameter BV Drain-source voltage DSS OFF State drain I DSS current Static drain-source r DS(on) ON state ...
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VIPER12A-E Table 5. Oscillation section Symbol Parameter Oscillator frequency F OSC total variation Table 6. PWM comparator section Symbol Parameter Peak current I Dlim limitation I I shutdown current FBsd FB FB pin ...
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Pin connections and function 3 Pin connections and function Figure 2. Pin connection SOURCE 1 SOURCE VDD 4 Figure 3. Current and voltage conventions Table 9. Pin function Pin Name Power supply of the control circuits. Also ...
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VIPER12A-E 4 Rectangular U-I output characteristics Figure 4. Rectangular U-I output characteristics for battery charger A complete regulation scheme can achieve combined and accurate output characteristics. Figure 4. presents a secondary feedback through an optocoupler driven by a TSM101. This ...
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Wide range of VDD voltage 5 Wide range of V The V pin voltage range extends from This feature offers a great flexibility in DD design to achieve various behaviors. In chosen to supply the ...
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VIPER12A-E 6 Feedback pin principle of operation A feedback pin controls the operation of the device. Unlike conventional PWM control circuits which use a voltage input (the inverted input of an operational amplifier), the FB pin is sensitive to current. ...
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Feedback pin principle of operation The current limitation is obtained with the FB pin shorted to ground ( negative current sourced by this pin, and expressed by: By reporting this expression in the previous one possible ...
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VIPER12A-E 7 Startup sequence Figure 7. Startup sequence This device includes a high voltage start up current source connected on the drain of the device. As soon as a voltage is applied on the input of the converter, this start ...
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Overvoltage threshold 8 Overvoltage threshold An overvoltage detector on the V exceeds V . This is illustrated in DDovp overvoltage event. Note that this event is only latched for the time needed and then the device ...
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VIPER12A-E 9 Operation pictures Figure 9. Rise and fall time Figure 10. Start- DD0 V DDhyst V DDoff I DDch Figure 11. Restart duty-cycle current DDon V = 100 ...
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Operation pictures Figure 12. Peak drain current vs feedback current Figure 13. Thermal shutdown 14/21 Doc ID 11977 Rev 2 VIPER12A-E ...
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VIPER12A-E Figure 14. Switching frequency vs temperature Figure 15. Current limitation vs temperature Doc ID 11977 Rev 2 Operation pictures 15/21 ...
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Package mechanical data 10 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 ...
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VIPER12A-E Table 10. DIP8 mechanical data Ref Package Weight Figure 16. Package dimensions Databook (mm) Min. Nom. 0.38 2.92 3.30 0.36 0.46 1.14 1.52 0.20 0.25 9.02 ...
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Package mechanical data Table 11. SO8 mechanical data Dim ddd Figure 17. Package dimensions 18/21 Databook (mm) Nom Min 1.35 0.10 1.10 0.33 0.19 4.80 3.80 1.27 5.80 ...
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... VIPER12A-E 11 Order codes Table 12. Order codes Order codes VIPER12ASTR-E VIPER12AS-E VIPER12ADIP-E Package SO-8 SO-8 DIP-8 Doc ID 11977 Rev 2 Order codes Packaging Tape and reel Tube Tube 19/21 ...
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Revision history 12 Revision history Table 13. Document revision history Date 09-Jan-2006 13-Dec-2010 20/21 Revision 1 Initial release. Updated Table 3 on page 2 on page 13. Doc ID 11977 Rev 2 VIPER12A-E Changes 4, Table 4 on page 4 ...
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... VIPER12A-E Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...