NCP1252 ON Semiconductor, NCP1252 Datasheet
NCP1252
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NCP1252 Summary of contents
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... ATX power supplies. Thanks to the use of an internally fixed timer, NCP1252 detects an output overload without relying on the auxiliary Vcc. A Brown−Out input offers protection against low input voltages and improves the converter safety. Finally a SOIC8 package saves PCB space and represents a solution of choice in cost sensitive project ...
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... This device contains latch−up protection and exceeds 100 mA per JEDEC Standard JESD78. Table 3. ORDERING INFORMATION Device NCP1252ADR2G NCP1252BDR2G †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specification Brochure, BRD8011/D. NCP1252 1 8 Vcc ...
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Figure 1. Internal Circuit Architecture http://onsemi.com 3 ...
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Table 4. ELECTRICAL CHARATERISTICS ( kW nF. For typical values DRV Characteristics SUPPLY SECTION AND V MANAGEMENT CC Startup threshold at which driving pulses are authorized Minimum Operating ...
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Table 4. ELECTRICAL CHARATERISTICS ( kW nF. For typical values DRV Characteristics DRIVE OUTPUT Output voltage fall−time Clamping voltage (maximum gate voltage) www.datasheet4u.com High−state voltage drop CYCLE SKIP ...
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TEMPERATURE (°C) Figure 4. Start−up Current (I Temperature SUPPLY VOLTAGE Vcc (V) Figure 6. Supply Current (I 300 250 200 150 100 ...
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TEMPERATURE (°C) Figure 10. Propagation Delay from CS to DRV vs. Junction Temperature 108 106 104 102 100 −40 − ...
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TEMPERATURE (°C) Figure 16. Maximum Duty−cycle, B Version vs. Junction Temperature −40 − TEMPERATURE (°C) Figure 18. Drive ...
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TEMPERATURE (°C) Figure 22. Soft Start Completion Voltage Threshold vs. Junction Temperature 1.10 1.08 1.06 1.04 1.02 1.00 0.98 0.96 0.94 0.92 0. SUPPLY VOLTAGE Vcc (V) Figure ...
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... Introduction The NCP1252 hosts a high−performance current−mode controller specifically developed to drive power supplies designed for the ATX and the adapter market: • Current Mode operation: implementing peak current−mode control topology, the circuit offers www.datasheet4u.com UC384X−like features to build rugged power supplies. ...
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V = 6.0 V FBOL www.datasheet4u.com 0.3 V skip Startup Sequence: The startup sequence is activated when Vcc pin reaches V level. Once the startup sequence has been activated CC(on) the internal delay ...
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V pin CC V CC(on) BO pin www.datasheet4u.com pin DRV pin When the BO pin is grounded, the controller is shut down and the SS pin is internally grounded in order to discharge the soft start capacitor ...
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The following figure illustrates a soft start sequence. www.datasheet4u.com Brown−Out Protection By monitoring the level on BO pin, the controller protects the forward converter against low input voltage conditions. When the BO pin level falls below the V controllers stops ...
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bulkon R + BOlo bulkoff R can be also written independently of R BOup substituting Equation 4 into Equation 3 as follow: V bulkon R + BOup From Equation 4 and Equation 5, the ...
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... Rcomp Rsense In the NCP1252, the internal ramp swings with a slope of int forward application the secondary−side downslope viewed on a primary side requires a projection over the sense resistor R . Thus: sense ( out S + sense L out where: • output voltage level out • ...
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Internal ramp compensation level Secondary−side downslope projected over the sense resistor is sense Natural primary ramp: www.datasheet4u.com S Thus the natural ramp compensation is: Here the natural ramp compensation is lower than the desired ramp compensation, so ...
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... S 5.80 6.20 0.228 1.52 0.060 4.0 0.155 1.270 0.050 mm SCALE 6:1 inches ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative INCHES MIN MAX 0.197 0.157 0.069 0.020 0.050 BSC 0.010 0.010 0.050 0.020 0.244 NCP1252/D ...