ML4804 Fairchild, ML4804 Datasheet
ML4804
Related parts for ML4804
ML4804 Summary of contents
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... Power Factor Correction and PWM Controller Combo GENERAL DESCRIPTION The ML4804 is a controller for power factor corrected, switched mode power supplies. Power Factor Correction (PFC) allows the use of smaller, lower cost bulk capacitors, reduces power line loading and stress on the switching FETs, and results in a power supply that fully complies with IEC1000-3-2 specification ...
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... Oscillator timing node; timing set RAMP 2 When in current mode, this pin functions as the current sense input; when in voltage mode the PWM modulation ramp input. 2 ML4804 16-Pin PDIP (P16) 16-Pin Narrow SOIC (S16N) IEAO 1 16 VEAO SENSE ...
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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 OPERATING CONDITIONS + 0.3V CCZ 10mA Temperature Range ML4804CX .................................................... 0°C to 70°C ML4804IX .................................................. -40°C to 85°C = 52.3kΩ 470pF Operating Temperature Range (Note CONDITIONS VEAO = 3 ...
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... ML4804 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER TRI-FAULT DETECT Fault Detect HIGH Time to Fault Detect HIGH Fault Detect LOW V OVP COMPARATOR CC Threshold Voltage Hysteresis PFC I COMPARATOR LIMIT Threshold Voltage (PFC Gain Modulator Output) LIMIT TH Delay to Output DC I COMPARATOR LIMIT Threshold Voltage Input Bias Current ...
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... OUT I = -100mA OUT I = 10mA OUT 20mA OUT I = 100mA OUT C = 1000pF 12V 14V (Note 4) pin (VEAO - 0.625)] ; VEAO =5V. AC MAX ML4804 MIN TYP MAX UNITS 7.4 7.5 7 0.4 % 7.35 7. 0.4 0.8 V 0.7 2.0 V ...
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... ML4804 TYPICAL PERFORMANCE CHARACTERISTICS Voltage Error Amplifier (VEA) Transconductance (g 180 160 140 120 100 –500 0 IEA INPUT VOLTAGE (mV) Current Error Amplifier (IEA) Transconductance (g 6 180 160 140 120 100 (V) 480 420 360 300 ...
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... PFC SECTION Gain Modulator Figure 1 shows a block diagram of the PFC section of the ML4804. 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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... TriFault Detect To improve power supply reliability, reduce system component count, and simplify compliance to UL 1950 safety standards, the ML4800 (ML4804) includes TriFault Detect. This feature monitors VFB (Pin 15) for certain PFC fault conditions. In the case of a feedback path failure, the output of the PFC could go out of safe operating limits ...
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... PFC will restart. If the PFC V again encounters an over voltage condition, CC the protection cycle will repeat. Note that the PWM stage of the ML4804 remains operational even when the PFC goes into V OVP shutdown. CC For a real-world example, assume that the bootstrap supply is derived from a conventional boost inductor winding and rectified using Shottky diodes ...
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... C PWM SECTION Pulse Width Modulator The PWM section of the ML4804 is straightforward, but there are several points which should be noted. Foremost among these is its inherent synchronization to the PFC section of the device, from which it also derives its basic timing ...
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... FUNCTIONAL DESCRIPTION No voltage error amplifier is included in the PWM stage of the ML4804, as this function is generally performed on the output side of the PWM’s isolation boundary. To facilitate the design of optocoupler feedback circuitry, an offset has been built into the PWM’s RAMP 2 input which allows ...
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... ML4804 FUNCTIONAL DESCRIPTION Generating V CC The ML4804 is a voltage-fed part. It requires an external 15V, ±10% (or better) shunt voltage regulator, or some other V regulator, to regulate the voltage supplied to CC the part at 15V nominal. This allows low power dissipation while at the same time delivering 13V nominal gate drive at the PWM OUT and PFC OUT outputs ...
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... Figure 6. 100W Power Factor Corrected Power Supply, Designed Using Micro Linear Application Note 33 REV. 1.0.2 3/9/2001 ML4804 13 ...
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... ORDERING INFORMATION PART NUMBER ML4804CP ML4804CS ML4804IP ML4804IS 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; ...