UC3842A-D08-T UTC [Unisonic Technologies], UC3842A-D08-T Datasheet
UC3842A-D08-T
Related parts for UC3842A-D08-T
UC3842A-D08-T Summary of contents
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... Suppression *High current totem pole output to drive MOSFET directly *Internally trimmed band gap reference *500kHz operation ORDERING INFORMATION Ordering Number Normal Lead Free Plating UC3842A-D08-T UC3842AL-D08-T UC3842A-S08-R UC3842AL-S08-R UC3842A-S08-T UC3842AL-S08-T UC3843A-D08-T UC3843AL-D08-T UC3843A-S08-R UC3843AL-S08-R ...
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... UC3842A/3843A PIN CONFIGURATION Current Sense BLOCK DIAGRAM V 8 REF Internal Bias VFB 2 COMP 1 3 CURRENT SENSE RT/CT 4 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw COMP RT/ REF S/R V REF Good 1/2V Logic REF 1/3V REF 1V ERROR AMPLIFIER OSCILLATOR LINEAR INTEGRATED CIRCUIT V 8 REF Output ...
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... UC3842A/3843A ABSOLUTE MAXIMUM RATINGS PARAMETER Supply Voltage(Low Impedance Source) Supply Voltage(I <30mA) CC Output Current ( Peak ) Output Energy (capacity Load) Analog Inputs(pin 2,3) Error Amplifier Output Sink Current Power Dissipation( Ta≦25°C) Derated at Ta>25°C Junction Temperature Storage Temperature Note Absolute maximum ratings are those values beyond which the device which the device could be permanently damaged ...
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... UC3842A/3843A ELECTRICAL CHARACTERISTICS(Cont.) PARAMETER Current Sense section Gain Maximum Input signal PSRR Input Bias Current Delay to Output Output Section Low Output Level High Rise Time Fall Time Under-Voltage Lockout Output Section 3842A Start Threshold 3843A 3842A Min. Operating Voltage 3843A PWM Section ...
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... UC3842A/3843A OPEN-LOOP LABORATORY TEST FIXTURE RT Error Amp Adjust 5kΩ CT High peak current associated with capacity loads necessitate careful grounding techniques. Timing and bypass capacitors should be connected close to pin 5 in single point GND. The transistor and 5kΩ potentio-meter are used to sample the oscillator waveform and apply an adjustable Ramp to Pin 3. ...
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... UC3842A/3843A CURRENT SENSE CIRCUIT Peak current (Is) determined by the formula: Ismax=10V/Rs. A small RC filter be required to suppress switch transients. SLOPE COMPENSATION A fraction of the oscillator ramp can be resistively summed with the current sense signal to provide slope compensation for converts requiring duty cycles over 50%.Note that capacitor C, forms a filter with R2 to suppress the leading edge switch spikes ...
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... SHUTDOWN TECHNIQUES Shutdown Shutdown UTC UC3842A 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 caused the output of PWM comparator to be high(refer to block diagram).The PWM latch is reset dominant so that the output will remain low until the next clock cycle after the shutdown condition at pins 1 and/ removed . In one example, an externally latched shut – ...
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... UC3842A/3843A TYPICAL CHARACTERISTICS Output Saturation Characteristics 4 Vcc=15V Ta=+25℃ 3 Ta=-40℃ 0.01 0.1 Output Current (Sourse or Sink Current ) (A) V Temperature Drift REF 5.02 5.01 5.00 4.99 4.98 4.97 4.96 -50 - 100 125 150 Temperature (℃) Icc Temperature Drift -50 - Temperature (℃) UNISONIC TECHNOLOGIES CO., LTD www ...
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... UC3842A/3843A UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury ...