ml4801 Fairchild Semiconductor, ml4801 Datasheet
ml4801
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ml4801 Summary of contents
Page 1
... The PFC frequency of the ML4801 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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... Connection point for the PWM soft start capacitor 6 V PWM voltage feedback input Connection for oscillator frequency T T setting components 8 RAMP 1 PFC ramp input 2 ML4801 16-Pin PDIP (P16) 16-Pin Narrow SOIC (S16N) IEAO 1 16 VEAO SENSE REF V RMS 4 ...
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... Storage Temperature Range ...................... –65°C to 150°C Lead Temperature (Soldering, 10 sec) ..................... 260°C Thermal Resistance (θ Plastic DIP ........................................................ 80°C/W 18V Plastic SOIC ................................................... 105°C/W + 0.3V CC OPERATING CONDITIONS 20mA Temperature Range ML4801CX ................................................. 0°C to 70°C ML4801IX ............................................... -40°C to 85°C = 29.4kΩ 15.4kΩ 270pF RAMP1 T CONDITIONS VEAO = 3 ...
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... ML4801 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER OVP COMPARATOR Threshold Voltage Hysteresis PFC I COMPARATOR LIMIT Threshold Voltage ∆PFC I Threshold - Gain Modulator Output LIMIT Delay to Output DC I COMPARATOR LIMIT Threshold Voltage Input Bias Current Delay to Output V OK COMPARATOR IN Threshold Voltage Hysteresis GAIN MODULATOR Gain (Note 3) ...
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... -20mA OUT I = -100mA OUT I = -10mA OUT 20mA OUT I = 100mA OUT C = 1000pF 12V 14V pin (VEAO - 0.625V ML4801 MIN TYP MAX UNITS 7.4 7.5 7 0.4 % 7.35 7. 0.4 0.8 V 0.7 2.0 V 0.4 0 0.8 ...
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... PFC SECTION Gain Modulator Figure 1 shows a block diagram of the PFC section of the ML4801. 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 voltage, and PFC output voltage. There are three inputs to the gain modulator ...
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... PFC OUTPUT DRIVER ≅ V /1.6kΩ). The negative SENSE SENSE represents the sum of all currents SENSE of the boost MOSFET(s) and one to monitor D is adequately negative to cancel this increased pin. SENSE pin, as well as being a part of the current ML4801 REF 14 PFC OUT 12 SENSE 7 ...
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... FB FB The oscillator frequency is set by the values of R The oscillator frequency is set by the values of R which determine the ramp and off-time of the ML4801's which determine the ramp and off-time of the ML4801's master oscillator: master oscillator: f OSC The deadtime of the oscillator is derived from the ...
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... C SS Generating V Generating V The ML4801 is a voltage-fed part. It requires an external The ML4801 is a voltage-fed part. It requires an external 15V±10% or better Zener shunt voltage regulator, or some 15V±10% or better Zener shunt voltage regulator, or some other V other V the part at 15V nominal. This allows a low power the part at 15V nominal ...
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... ML4801 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. The error amplifier output voltage is then compared with the modulating ramp. When the modulating ramp reaches the level of the error amplifier output voltage, the switch will be turned OFF ...
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... Figure 5. I vs. V VEAO 200 160 120 (V) Figure REV. 1.1 3/9/2001 OTA ML4801 180 (V) Figure OTA 500 RMS (V) Figure Multiplier ...
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... C7 R19 220pF 220Ω R7B C6 R12 178kΩ 1µF 27kΩ VDC REF V CC PFC OUT PWM OUT GND D8 1N5818 RAMP 2 ML4801 C17 R6 220pF 36.5kΩ R10 20kΩ 6.2kΩ Q2 IRF830 R17 33Ω D5 BYV26C D7 R30 L2 D11 16V 4.7kΩ 15µH ...
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... SEATING PLANE 0.016 - 0.022 (0.40 - 0.56) Package: S16N 16-Pin Narrow SOIC 0.386 - 0.396 (9.80 - 10.06) 0.148 - 0.158 0.228 - 0.244 PIN 1 ID (3.76 - 4.01) (5.79 - 6.20) 0.050 BSC (1.27 BSC) 0.059 - 0.069 (1.49 - 1.75) 0.012 - 0.020 0.004 - 0.010 (0.30 - 0.51) SEATING PLANE (0.10 - 0.26) ML4801 0.295 - 0.325 (7.49 - 8.26) 0.008 - 0.012 0º - 15º (0.20 - 0.31) 0º - 8º 0.015 - 0.035 0.006 - 0.010 (0.38 - 0.89) (0.15 - 0.26) 13 ...
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... ORDERING INFORMATION PART NUMBER ML4801CP ML4801CS ML4801IP ML4801IS 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; ...