UC3843B ON Semiconductor, UC3843B Datasheet
UC3843B
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UC3843B Summary of contents
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... The UC3842B, UC3843B series are high performance fixed frequency current mode controllers. They are specifically designed for Off–Line and dc–to–dc converter applications offering the designer a cost–effective solution with minimal external components. These integrated circuits feature a trimmed oscillator for precise duty cycle ...
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... Startup threshold before setting Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible for UC3842B, UC3843B; –25 C for UC2842B, UC2843B; –40 C for UC3842BV, UC3843BV low T = +70 C for UC3842B, UC3843B; +85 C for UC2842B, UC2843B; +105 C for UC3842BV, UC3843BV ...
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... Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible for UC3842B, UC3843B; –25 C for UC2842B, UC2843B; –40 C for UC3842BV, UC3843BV low T = +70 C for UC3842B, UC3843B; +85 C for UC2842B, UC2843B; +105 C for UC3842BV, UC3843BV high NCV3843BV – +125 C. Guaranteed by design. NCV prefix is for automotive and other applications requiring site and ...
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... Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible for UC3842B, UC3843B; –25 C for UC2842B, UC2843B; –40 C for UC3842BV, UC3843BV low T = +70 C for UC3842B, UC3843B; +85 C for UC2842B, UC2843B; +105 C for UC3842BV, UC3843BV high NCV3843BV – +125 C. Guaranteed by design. NCV prefix is for automotive and other applications requiring site and ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 6. Error Amp Small Signal Transient Response Figure 8. Error Amp Open Loop Gain and Phase versus Frequency Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 12. Reference Load Regulation Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Pin 8–Pin 14–Pin Function 1 1 Compensation 2 3 Voltage Feedback 3 5 Current Sense Gnd 6 10 Output ref 8 Power Ground Gnd 2,4,6,13 NC PIN FUNCTION DESCRIPTION Description This pin is the Error Amplifier output and is made available for loop compensation. ...
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... Capacitor Current Sense Comparator and PWM Latch to T The UC3842B, UC3843B operate as a current mode controller, whereby output switch conduction is initiated by , the oscillator T the oscillator and terminated when the peak inductor current reaches the threshold level established by the Error Amplifier Output/Compensation (Pin 1). Thus the error signal controls the peak inductor current on a cycle– ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 18. Representative Block Diagram Figure 19. Timing Diagram http://onsemi.com 9 ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Undervoltage Lockout Two undervoltage lockout comparators have been incorporated to guarantee that the IC is fully functional before the output stage is enabled. The positive power supply terminal (V ) and the reference output (V CC each monitored by separate comparators. Each has built–in hysteresis to prevent erratic output behavior as their respective thresholds are crossed ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 20. Continuous Current Waveforms + + ) ) Figure 22. External Duty Cycle Clamp and Multi–Unit Synchronization Figure 21. External Clock Synchronization ) Figure 23. Adjustable Reduction of Clamp Level http://onsemi.com ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 24. Soft–Start Circuit V Pin 5 [ Figure 26. Current Sensing Power MOSFET [ ) + * * Figure 25. Adjustable Buffered Reduction of Clamp Level with Soft–Start DS(on) r DM(on Figure 27. Current Waveform Spike Suppression http://onsemi.com ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 28. MOSFET Parasitic Oscillations + Figure 30. Isolated MOSFET Drive http://onsemi.com Figure 29. Bipolar Transistor Drive * Figure 31. Latched Shutdown 13 ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 32. Error Amplifier Compensation Figure 33. Slope Compensation http://onsemi.com 14 ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Figure 34 Off–Line Flyback Regulator Test Conditions Line Regulation: 5 130 Vac Load Regulation: 5 115 Vac 1 4.0 A out 115 Vac 100 mA to 300 mA out Output Ripple: 5 115 Vac Efficiency V = 115 Vac in All outputs are at nominal load currents, unless otherwise noted ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV Device UC384XBD UC384XBDR2 UC384XBD1 UC384XBD1R2 UC384XBN UC3842BN1 UC284XBD UC2843BDR2 UC284XBD1 UC284XBD1R2 UC284XBN UC3843BVD UC384XBVDR2 UC384XBVD1 UC384XBVD1R2 UC3843BVN NCV3843BVDR2 X indicates either define specific device part numbers. ORDERING INFORMATION Operating Temperature Range Package SO–14 SO–14 SO– + + SO–8 PDIP–8 PDIP– ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV MARKING DIAGRAMS PDIP–8 N SUFFIX CASE 626 8 8 UC384xBN UC3843BVN FAWL YYWW YYWW 1 1 SO–8 D1 SUFFIX CASE 751 8 8 384xB 384xB ALYW ALYWV 1 1 SO–14 D SUFFIX CASE 751A 14 14 UC384xBD UC384xBVD AWLYWW AWLYWW WL, L YY Work Week *This marking diagram also applies to NCV3843BV ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV –B– F –A– NOTE 2 C –T– –X– –Y– –Z– PACKAGE DIMENSIONS PDIP–8 N SUFFIX CASE 626–05 ISSUE SO–8 D1 SUFFIX CASE 751–07 ISSUE http://onsemi.com ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV –A– –B– G –T– PACKAGE DIMENSIONS SO–14 D SUFFIX CASE 751A–03 ISSUE http://onsemi.com ...
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... UC3842B, UC3843B, UC2842B, UC2843B, NCV3843BV SENSEFET is a trademark of Semiconductor Components Industries, LLC. ON Semiconductor and are trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “ ...