ML4812IP Fairchild Semiconductor, ML4812IP Datasheet
ML4812IP
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ML4812IP Summary of contents
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GENERAL DESCRIPTION The ML4812 is designed to optimally facilitate a peak current control boost type power factor correction system. Special care has been taken in the design of the ML4812 to increase system noise immunity. The circuit includes a precision ...
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ML4812 PIN CONFIGURATION ML4812 16-Pin PDIP (P16) I SENSE OUT OUT 3 14 EA– OVP SINE 6 11 RAMP COMP TOP VIEW PIN ...
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ABSOLUTE MAXIMUM RATINGS 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. Supply Current (I ) ............................................... 30mA CC Output Current ...
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ML4812 ELECTRICAL CHARACTERISTICS PARAMETER GAIN MODULATOR I Input Voltage SINE Output Current (GM OUT) Bandwidth PSRR OVP COMPARATOR Input Offset Voltage Hysteresis Input Bias Current Propagation Delay PWM COMPARATOR: I SENSE Input Offset Voltage Input Offset Current Input Common Mode ...
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FUNCTIONAL DESCRIPTION OSCILLATOR The ML4812 oscillator charges the external capacitor (C with a current (I ) equal to 5/R SET SET voltage reaches the upper threshold, the comparator changes state and the capacitor discharges to the lower threshold through Q1. ...
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ML4812 FUNCTIONAL DESCRIPTION OUTPUT DRIVER STAGE The ML4812 output driver peak output high speed totem pole circuit designed to quickly drive capacitive loads, such as power MOSFET gates. (Figure 3) ERROR AMPLIFIER The ML4812 error amplifier is ...
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TYPICAL APPLICATIONS INPUT INDUCTOR (L1) SELECTION The central component in the regulator is the input boost inductor. The value of this inductor controls various critical operational aspects of the regulator. If the value is too low, the input current distortion ...
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TYPICAL APPLICATIONS The recommended maximum duty cycle is 95% at 100KHz to allow time for the input inductor to dump its energy to the output capacitors. For example, if: V 380V and D (max) = 0.95, then substituting in (3) ...
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TYPICAL APPLICATIONS CURRENT SENSE AND SLOPE (RAMP) COMPENSATION COMPONENT SELECTION Slope compensation in the ML4812 is provided internally. Rather than adding slope to the noninverting input of the PWM comparator actually subtracted from the voltage present at the ...
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ML4812 TYPICAL APPLICATIONS Choose 4.75k , 1%. One more critical component in the voltage regulation loop is the feedback capacitor for the error amplifier. The voltage loop bandwidth should be set such that it rejects the 120Hz ripple which is ...
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TYPICAL APPLICATIONS MATERIAL Powdered Iron Powdered Iron Molypermalloy MAGNETICS TIPS L1 — Main Inductor As shown in Table 1, one of several toroidal cores can be used for L1. The T184-40 core above is the most economical, but has lower ...
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ML4812 Figure 12. Typical Application, 200W Power Factor Correction Circuit 12 REV. 1.0 10/10/2000 ...
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REFERENCE DESCRIPTION C1 630V Film (250VAC) C3, C 6.8nF, 1KV Ceramic disk H C5, C6 680 F, 200V Electrolytic C8, C9 0.1 F, 50V Ceramic C10, C19 1 F, 50V Ceramic C11 0.001 F, 50V Ceramic C15 ...
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ML4812 Figure 13. 1kW Input Power, Power Factor Correction Circuit 14 REV. 1.0 10/10/2000 ...
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PHYSICAL DIMENSIONS 16 PIN 0.02 MIN (0.50 MIN) (4 PLACES) 0.170 MAX (4.32 MAX) 0.125 MIN (3.18 MIN) 0.385 - 0.395 (8.89 - 10.03) 0.350 - 0.356 (8.89 - 9.04) PIN 1 ID 0.042 - 0.048 6 ...
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... ML4812 ORDERING INFORMATION PART NUMBER ML4812CP ML4812CQ ML4812IP ML4812IQ 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; ...