ncp1338 ON Semiconductor, ncp1338 Datasheet
ncp1338
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ncp1338 Summary of contents
Page 1
... NCP1338 PWM Current-Mode Controller for Free Running Quasi-Resonant Operation The NCP1338 combines a true current mode modulator and a demagnetization detector which ensures full Borderline/Critical Conduction Mode in any load/line conditions together with minimum drain voltage switching (Quasi-Resonant operation). The transformer core reset detection is done internally, without using any external signal, due to the Soxyless concept ...
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... When V reaches 18 internal OVP stops the output pulses. CC • Connected to the high-voltage rail, this pin injects a constant current into the V bulk capacitor and ensures a clean lossless startup sequence NCP1338 Rcomp Figure 1. Typical Application Schematic http://onsemi.com 2 ...
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... Setpoint kHz Low-pass filter 500 mV FAULT Vdd if Zener activated Ton CS 350 ns LEB GND NCP1338 Q PERM. LATCH Vdd timeout V < TSD TSD Startup Soxyless 7.5 ms min Ton period SStart 67 ms Ton max Ton SSkip ...
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... Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. 1. This device contains latchup protection and exceeds 100 mA per JEDEC standard JESD78. NCP1338 ) and Pin 5 (DRV and Pin 5 (DRV) ...
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... Propagation Delay from Current Detection to Gate OFF State Leading Edge Blanking Duration Internal Current Offset Injected on the CS Pin during ON Time (Over Power Compensation Pin 1 and Vpin3 = 0 2 Pin 1 and Vpin3 = 0.5 V Maximum ON Time NCP1338 = 25°C, for min/max values T J Pin ...
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... Sourcing 15 mA) Propagation Delay from Demag Detection to Gate ON State (I Slope of 500 A/s) GATE Blanking Window after Gate OFF State before Detecting Demagnetization Timeout on Demag Signal Maximum OFF Time Minimum Switching Period NCP1338 = 25°C, for min/max values T J Pin ...
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... CC • Overcurrent Protection (OCP): When the feedback current is below minimum value, a fault is detected. If this fault is present for more than 80 ms, NCP1338 enters an auto-recovery soft burst mode. All pulses are stopped and the V capacitor discharges down to CC 5.0 V. Then, by monitoring the V ...
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... If the current Setpoint is above the fault level, FAULT flag is raised. CS Setpoint Fault V CSstby CS V CSLimit FAULT SS TIMER When FAULT is activated, the 80 ms timer starts NCP1338 Timing Diagrams When the timer ends, if FAULT is not activated anymore, the controller works normally. Figure 3. Startup Sequence http://onsemi.com 8 ...
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... When the current setpoint rises above fault level, FAULT flag is activated CSLimit FAULT When FAULT flag TIMER is activated, timer is restarted Fault Timer NCP1338 nd Restart on 2 cycle Overload is removed here Output pulses are stopped. SS Figure 4. Overload http://onsemi.com 9 Normal Startup ...
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... VCC VCC on VCC min CS Setpoint VCS rippleOUT VCS rippleIN CS (envelope) Min T ON NCP1338 Soft-Skip on each re-start Figure 5. Soft-Skip Mode in Standby http://onsemi.com 10 ...
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... C the total capacitance present on the MOSFET DRAIN NCP1338 MOSFET (modelized by the Crss capacitance between Gate and Drain): a negative current (flowing out of DRV pin) takes place during the decreasing part of the Drain asymptote oscillation, and a positive current (entering into the DRV IN pin) during the increasing part ...
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... Soft Burst Mode (Protection Mode) The NCP1338 features a fault timer to detect an overload completely independently of the V CC the feedback loop asks for the maximum power, a fault is detected, and an internal timer is started ...
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... NCP1338 V in 3.3 meg BO Rhyst 11 k Figure 8. Internal Implementation of BO Pin http://onsemi.com + Permanent Latch - + Enable + + 3 V Vdd 10 mA current source activated when V is high BOK + BOK - + 500 mV 13 ...
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... - - -T- SEATING PLANE 0.25 (0.010 NCP1338 PACKAGE DIMENSIONS PDIP-7 P SUFFIX CASE 626B-01 ISSUE SOIC-7 D SUFFIX CASE 751U-01 ISSUE D 0.25 (0.010 http://onsemi.com 14 NOTES: 1 ...
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... Soft-Skip is a trademark of Semiconductor Components Industries, LLC (SCILLC). The product described herein (NCP1338), may be covered by the following U.S. patents: 6,362,067, 5,073,850, 6,385,060, 6,587,357, 6,469,484, 6,940,320, 5,862,045. 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 ...