ml4841 Fairchild Semiconductor, ml4841 Datasheet
ml4841
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ml4841 Summary of contents
Page 1
... The PFC frequency of the ML4841 is automatically set at half that of the PWM frequency generated by the internal oscillator. This technique allows the user to design with smaller output components while maintaining the optimum operating frequency for the PFC ...
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... Positive supply (connected to an internal shunt regulator Buffered output for the internal 7.5V reference REF PFC transconductance voltage error amplifier input VEAO PFC transconductance voltage error amplifier output 2 ML4841 16-Pin PDIP (P16) IEAO 1 16 VEAO SENSE REF ...
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... VEAO = 3.75V NON INV INV Note 2 ∆V = ±0.5V OUT ∆V = ±0.5V 1.5V IN OUT < V < 0.5V CCZ CC CCZ VEAO = 3.75V NON INV INV ML4841 Max. Units 0.3 V CCZ 500 mA 500 mA 1.5 mJ 150 °C 150 °C 260 ° ...
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... ML4841 Electrical Characteristics Unless otherwise specified 25mA Operating Temperature Range (Note 1) Symbol Parameter Input Bias Current Output High Voltage Output Low Voltage Source Current Sink Current Open Loop Gain PSRR OVP Comparator Threshold Voltage Hysteresis PFC I Comparator LIMIT Threshold Voltage ∆ ...
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... OUT I = 10mA OUT 20mA OUT I = 100mA OUT C = 1000pF L 25mA < I < 55mA CC Load, Temp V = 11.2V < 0.5V CCZ L pin (VEAO - 1.5V ML4841 = 400pF 270pF RAMP1 A Min. Typ. Max. Units 7.4 7.5 7 0.4 % 7.25 7. 0.4 0.8 V 0.7 2 ...
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... ML4841 Typical Performance Characteristics 250 200 150 100 (V) Voltage Error Amplifier (VEA) Transconductance (g 16 IEAO VEAO V FB VEA IEA 3.5kΩ 2. GAIN V RMS MODULATOR 4 3.5kΩ I SENSE 3 RAMP 250 200 150 100 ...
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... PFC Section Gain Modulator Figure 1 shows a block diagram of the PFC section of the ML4841. The gain modulator is the heart of the PFC this circuit block which controls the response of the current loop to line voltage waveform and frequency, rms line volt- age, and PFC output voltage. There are three inputs to the gain modulator ...
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... V should be set at a level where the active and passive external power components and the ML4841 are within their safe operating voltages, but not so low as to interfere with the boost voltage regulation loop. Error Amplifier Compensation The PWM loading of the PFC can be modeled as a negative resistor ...
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... The gain vs. input voltage of the ML4841’s voltage error amplifier has a specially shaped nonlinearity such that under steady-state operating conditions the transconductance of the error amplifi ...
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... SS Figure 3. External Component Connections to V Generating V CC The ML4841 is a current-fed part. It has an internal shunt voltage regulator, which is designed to regulate the voltage internal to the part at 13.5V. This allows a low power dissi- pation while at the same time delivering 10V of gate drive at the PWM OUT and PFC OUT outputs important to ...
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... PRODUCT SPECIFICATION The ML4841 should be locally bypassed with a 10nF and a 1µF ceramic capacitor. In most applications, an electrolytic capacitor of between 100µF and 330µF is also required across the part, both for filtering and as part of the start-up bootstrap circuitry. Leading/Trailing Modulation Conventional Pulse Width Modulation (PWM) techniques employ trailing edge modulation in which the switch will turn on right after the trailing edge of the system clock ...
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... ML4841 VIN – REF RAMP OSC CLK U4 Figure 5. Leading/Trailing Edge Control Scheme 12 SW2 SW1 C1 RAMP VEAO VEAO DFF CMP + R Q – VSW1 Q CLK PRODUCT SPECIFICATION TIME TIME REV. 1.0.3 6/13/01 ...
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... C22 Q3 4.7µF IRF830 R23 R18 1.5kΩ 220Ω R20 C23 R26 1.1Ω 100nF 10kΩ TL431 C9 8.2nF C31 R11 1nF 750kΩ R8 C13 C14 2.37kΩ 100nF 1µF C8 C16 82nF 1µF ML4841 12VDC RTN R22 8.66kΩ R25 2.26kΩ 13 ...
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... ML4841 Mechanical Dimensions 16 PIN 0.02 MIN (0.50 MIN) 0.055 - 0.065 (4 PLACES) (1.40 - 1.65) 0.170 MAX (4.32 MAX) 0.016 - 0.022 0.125 MIN (0.40 - 0.56) (3.18 MIN) 14 inches (millimeters) Package: P16 16-Pin PDIP 0.740 - 0.760 (18.79 - 19.31) 0.240 - 0.260 0.295 - 0.325 (6.09 - 6.61) (7.49 - 8.26) 0.100 BSC (2.54 BSC) 0.015 MIN (0.38 MIN) SEATING PLANE PRODUCT SPECIFICATION 0.008 - 0.012 0° ...
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... ML4841 Ordering Information Part Number Temperature Range ML4841CP 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; ...