KA3844BD Fairchild Semiconductor, KA3844BD Datasheet
KA3844BD
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KA3844BD Summary of contents
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... Low Start up Current • Maximum Duty Clamp • UVLO With Hysteresis • Operating Frequency up to 500KHz Internal Block Diagram ©2002 Fairchild Semiconductor Corporation www.fairchildsemi.com Description The KA3842B/KA3843B/KA3844B/KA3845B are fixed frequency current-mode PWM controller. They are specially designed for Off - Line and DC-to-DC converter applications with minimum external components ...
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KA3842B/KA3843B/KA3844B/KA3845B Absolute Maximum Ratings Parameter Supply Voltage Output Current Analog Inputs (Pin 2.3) Error Amp Output Sink Current Power Dissipation (8DIP) A Power Dissipation (14SOP) A Storage Temperature Range Lead Temperature (Soldering, ...
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Electrical Characteristics (V =15V, R =10K , C =3.3nF Parameter REFERENCE SECTION Reference Output Voltage Line Regulation Load Regulation Short Circuit Output Current OSCILLATOR SECTION Oscillation Frequency Frequency Change with Voltage Oscillator Amplitude ERROR AMPLIFIER SECTION ...
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KA3842B/KA3843B/KA3844B/KA3845B 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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KA3842B/KA3843B/KA3844B/KA3845B Figure 5. Oscillator Waveforms and Maximum Duty Cycle Oscillator timing capacitor charged charge 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 KA3842B 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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KA3842B/KA3843B/KA3844B/KA3845B Mechanical Dimensions Package 6.40 0.20 0.252 0.008 # 7.62 0.300 8 Dimensions in millimeters 8-DIP 5.08 MAX 0.200 3.40 0.33 0.20 MIN 0.013 0.134 0.008 3.30 0.30 0.130 0.012 ...
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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 (Continued) Dimensions in millimeters 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 KA3842B/KA3843B/KA3844B/KA3845B 0.05 MIN 0.002 9 ...
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... KA3844B KA3845B KA3842BD KA3843BD 14-SOP KA3844BD KA3845BD 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 ...