UC3842G UTC [Unisonic Technologies], UC3842G Datasheet
UC3842G
Related parts for UC3842G
UC3842G Summary of contents
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... HIGH PERFORMANCE CURRENT MODE CONTROLLER DESCRIPTION ■ The UTC UC3842G of high performance current mode controller is specifically designed for off-line and DC-to-DC converter applications offering the designer a cost effective solution with minimal external components. This integrated circuit features approximately 300µA start up current, a precision reference trimmed the error amplifier input ...
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... UC3842G PIN CONFIGURATION COMP 1 PIN DESCRIPTION ■ PIN NO. PIN NAME I/O 1 COMP GND 6 OUT REF UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw LINEAR INTEGRATED CIRCUIT This pin is error amplifier output The error amplifier inverting input ...
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... UC3842G BLOCK DIAGRAM ■ UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw LINEAR INTEGRATED CIRCUIT QW-R103-036 ...
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... UC3842G ABSOLUTE MAXIMUM RATINGS PARAMETER Supply Voltage (Low Impedance Source) Supply Voltage (I <30mA) CC Output Current (Peak) Output Energy (Capacity load) Junction Temperature Operating Temperature Storage Temperature Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. ...
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... UC3842G ELECTRICAL CHARACTERISTICS (Cont.) PARAMETER OUTPUT SECTION Output Voltage With UVLO Active Output Voltage Output Voltage Rise and Fall time UNDER VOLTAGE LOCKOUT SECTION Startup Threshold Min Operating Voltage PWM SECTION Max Duty Cycle Minimum Duty Cycle TOTAL DEVICE Power Supply Zener Voltage ...
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... UC3842G OPEN-LOOP TEST CIRCUIT Ra 100k Vpwl adjust High peak current associated with capacity loads necessitate careful grounding techniques. Timing and bypass capacitors should be connected close to pin5 in single point GND. UNDER-VOLTAGE LOCKOUT During Under-Voltage Lockout, the output driver is biased to a high impedance state. Pin6 should be shunt to GND with a bleeder resistor to prevent activing the power switch with output leakage currents ...
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... UC3842G CURRENT SENSE CIRCUIT Peak current (I ) determined by the formula transients OSCILLATOR AND STANDBY MODE We can judge the state of output load through the voltage of PIN1. In order to reduce the standby power, it will reduce the OSC frequency at right load. When V frequency is 52KHz, the minimum frequency is 14KHz. ...
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... UC3842G SHUTDOWN TECHNIQUE Shutdown Shutdown UTC UC3842G can be accomplished by two methods; either raise pin 3 above 1V or pull Pin 1 below a voltage two diode drops above ground. 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 ...