NCP1378 ON Semiconductor, NCP1378 Datasheet
NCP1378
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NCP1378 Summary of contents
Page 1
... Over Voltage Protection (OVP). Once an OVP has been detected, the IC permanently latches off. The NCP1378 also features an efficient protective circuitry that, in presence of an overcurrent condition, disables the output pulses and enters a safe burst mode, trying to restart. Once the default has gone, the device auto− ...
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... Current sense input and skip 4 GND 5 Drv DataSheet U .com NCP1378 R* NCP1378 OVP and + Demag Figure 1. Typical Application Schematic Function The auxiliary FLYBACK signal ensures discontinuous operation and offers a fixed overvoltage detection level of 5.2 V. ...
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... Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected. 4 DataSheet U .com NCP1378 4.5 ms Delay Demag 8 ms Blanking 5 ...
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... Low State (Ipin 1 = −2.0 mA) Demag Propagation Delay Internal Input Capacitance at Vpin 1 = 1.0 V Internal Blanking Delay after T 1. Max value please see characterization curves DataSheet U .com NCP1378 (For typical values for min/max values T j Characteristic and VCC ON min = 60 kHz ...
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... TEMPERATURE ( C) Figure 5. Current Consumption (No Load) versus Temperature − TEMPERATURE ( C) Figure 7. HV Current Source at V versus temperature 4 DataSheet U .com NCP1378 TYPICAL CHARACTERISTICS 8.0 7.8 7.6 7.4 7.2 7 100 125 −25 Figure 4. V 2.2 2.0 1.8 1.6 1.4 1.2 1 100 125 −25 Figure 6. Current Consumption (1.0 nF Load) 1 ...
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... TEMPERATURE ( C) Figure 9. Drive Source Resistance versus 120 100 − TEMPERATURE ( C) Figure 11. Demagnetization Detection Threshold versus Temperature 10.0 9.5 9.0 8.5 8.0 7.5 7.0 6.5 − TEMPERATURE ( C) Figure 13. Minimum T 4 DataSheet U .com NCP1378 TYPICAL CHARACTERISTICS 100 125 Temperature 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3 100 125 7.0 6.5 6.0 5.5 5.0 4.5 4 ...
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... CC to startup. Overvoltage Protection (OVP): By sampling the plateau voltage on the demagnetization winding, the NCP1378 goes into latched fault condition whenever an over−voltage condition is detected. The controller stays fully latched in this position until the V cycled down to 4.0 V, e.g. when the user unplugs the power supply from the mains outlet and replugs it ...
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... NCP1378. To the opposite, in low output power conditions, no more ringing waves are present on the drain and the toggling of the current sense comparator alone initiates a new cycle start ...
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... An internal timer prevents any restart within 8.0 ms further to the driver going−low transition. This prevents the switching frequency to exceed (1.0/T 4 DataSheet U .com NCP1378 Demag RESTART Current Sense and Timeout Restart 5 ms Figure 19. When the primary natural ringing becomes too low, the current sense initiates a new cycle when FB passes the skip level. ...
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... DS When an OVP condition has been detected, the NCP1378 enters a latchoff phase and stops all switching operations. The controller stays fully latched in this position and the startup source being still active, it keeps the V CC state lasts until the V the user unplugs the power supply from the mains outlet ...
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... V. When this happens, NCP1378 immediately stops the switching pulses and unbiases all unnecessary logical blocks. The overall consumption drops, while keeping the gate grounded, and the V typically 5.5 V, the startup source turns−on again and a new startup sequence occurs, bringing V attempt to restart ...
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... IC CC consumption as soon NCP1378 is used and drives a MOSFET with total gate charge (Qg). The total average current is thus made of ICC1 (1.0 mA) plus the driver current, Fsw 1.8 mA. The total current is therefore 2.8 mA. The DV available to fully startup the circuit (e.g. never reach the 7.5 V UVLO during power on) is 8.4 – ...
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... Figure 28. This plot gathers waveforms captured at three different operating points: 4 DataSheet U .com NCP1378 st 1 Upper Plot: Free run, valley switching operation, Pout = Middle Plot: Min Toff clamps the switching frequency and selects the second valley Lowest Plot: The skip slices the second valley pattern and will further expand the burst as Pout goes low ...
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... −Y− G −Z− 0.25 (0.010) 4 DataSheet U .com NCP1378 PACKAGE DIMENSIONS SOIC−8 D SUFFIX CASE 751−07 ISSUE AC 0.25 (0.010 SEATING PLANE 0.10 (0.004 SOLDERING FOOTPRINT 7.0 0.275 0.6 0.024 http://onsemi.com ...
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... F A NOTE 2 −T− SEATING PLANE H G 0.13 (0.005 DataSheet U .com NCP1378 PACKAGE DIMENSIONS PDIP−7 P SUFFIX CASE 626B−01 ISSUE http://onsemi.com 15 NOTES: 1. DIMENSIONS AND TOLERANCING PER ASME Y14.5M, 1994. 2. DIMENSIONS IN MILLIMETERS. ...
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... The product described herein (NCP1378), may be covered by one or more of the following U.S. patents: 6,362,067, 6,385,060, 6,385,061, 6,429,709, 6,587,357, 6,633,193. There may be other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein ...