UC3844D Fairchild Semiconductor, UC3844D Datasheet
UC3844D
Specifications of UC3844D
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UC3844D Summary of contents
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... Operating Frequency up to 500KHz Internal Block Diagram * NORMALLY 8DIP/8SOP PIN NO 14SOP PINNO. * TOGGLE FLIP FLOP USED ONLY IN UC3844, UC3845 ©2002 Fairchild Semiconductor Corporation www.fairchildsemi.com Description The UC3842/UC3843/UC3844/UC3845 are fixed frequencycurrent-mode PWM controller. They are specially designed for Off-Line and converter applications with minimum external components ...
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UC3842/UC3843/UC3844/UC3845 Absolute Maximum Ratings Parameter Supply Voltage Output Current Analog Inputs (Pin 2.3) Error Amp Output Sink Current Power Dissipation (8DIP) A Power Dissipation (8SOP) A Power Dissipation ...
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Electrical Characteristics (V =15V, R =10k , C =3.3nF Parameter Symbol REFERENCE SECTION Reference Output Voltage Line Regulation Load Regulation Short Circuit Output Current OSCILLATOR SECTION Oscillation Frequency Frequency Change with Voltage Oscillator Amplitude ERROR ...
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UC3842/UC3843/UC3844/UC3845 Electrical Characteristics (V =15V, R =10k , C =3.3nF Parameter PWM SECTION Max. Duty Cycle Min. Duty Cycle TOTAL STANDBY CURRENT Start-Up Current Operating Supply Current Zener Voltage Adjust V above the start threshould before ...
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During Under-Voltage Lock-Out, the output driver is biased to a high impedance state. Pin 6 should be shunted to ground with a bleeder resistor to prevent activating the power switch with output leakage current. Peak current ( determined ...
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UC3842/UC3843/UC3844/UC3845 Figure 5. Oscillator Waveforms and Maximum Duty Cycle Oscillator timing capacitor charged discharge time, the internal clock signal blanks the output to the low state. Selection of R oscillator frequency and maximum duty ...
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Shutdown of the UC3842 can be accomplished by two methods; either raise pin 3 above 1V or pull pin 1 below a voltage two diode drops above ground. Either method causes the output of the PWM comparator to be high ...
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UC3842/UC3843/UC3844/UC3845 Mechanical Dimensions Package 6.40 0.20 0.252 0.008 # 7.62 0.300 8 8-DIP 5.08 MAX 0.200 3.40 0.33 0.20 0.013 0.134 0.008 3.30 0.30 0.130 0.012 MIN ...
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Mechanical Dimensions Package #1 #4 6.00 0.236 3.95 0.156 5.72 0.225 0.50 0.20 0.020 0.008 (Continued) 8-SOP 1.55 0.20 0.061 0.008 #8 #5 0.30 1.80 MAX 0.012 0.071 0.20 0.008 UC3842/UC3843/UC3844/UC3845 0.1~0.25 MIN 0.004~0.001 9 ...
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UC3842/UC3843/UC3844/UC3845 Mechanical Dimensions Package #1 #7 6.00 0.236 3.95 0.156 5.72 0.225 0.60 0.20 0.024 0.008 10 (Continued) 14-SOP 1.55 0.10 0.061 0.004 #14 #8 0.30 1.80 MAX 0.071 0.012 0.20 0.008 0.05 MIN 0.002 ...
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... Ordering Information Product Number UC3842N UC3843N UC3844N UC3845N UC3842D1 UC3843D1 UC3844D1 UC3845D1 UC3842D UC3843D UC3844D UC3845D Package Operating Temperature 8-DIP 8-SOP 14-SOP UC3842/UC3843/UC3844/UC3845 11 ...
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... UC3842/UC3843/UC3844/UC3845 DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. ...