ML4800 Fairchild Semiconductor, ML4800 Datasheet
ML4800
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ML4800 Summary of contents
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... ML4800 Power Factor Correction and PWM Controller Combo Features Block Diagram 16 VEAO V FB VEA 15 - IEA 1. GAIN V RMS MODULATOR 4 1.6k I SENSE 3 RAMP 1 7 RAMP 1.25V LIMIT V REF 9 General Description 1 POWER FACTOR CORRECTOR IEAO TRI-FAULT OVP ...
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... Positive supply Buffered output for the internal 7.5V reference REF 15 V PFC transconductance voltage error amplifier input FB 16 VEAO PFC transconductance voltage error amplifier output 2 ML4800 16-Pin PDIP (P16) 16-Pin Narrow SOIC (S16N) IEAO 1 16 VEAO SENSE 3 14 ...
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... A Conditions VEAO = 3.75V NON INV INV Note ±0.5V OUT V = ±0.5V 1.5V IN OUT 11V < V < 16. VEAO = 3.75V NON INV INV ML4800 Max. Units 0.3 V CCZ 1.5 µJ 150 °C 150 °C 260 °C 80 ° ...
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... ML4800 Electrical Characteristics Unless otherwise specified 15V Symbol Parameter Input Bias Current Output High Voltage Output Low Voltage Source Current Sink Current Open Loop Gain Power Supply Rejection Ratio OVP Comparator Threshold Voltage Hysteresis Tri-Fault Detect Fault Detect HIGH ...
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... I = -100mA OUT I = 10mA OUT 20mA OUT I = 100mA OUT C = 1000pF 12V 14V pin (VEAO - 0.625)] ; VEAO =5V. AC MAX ML4800 Min. Typ. Max. Units 350 650 ns 3.5 5.5 7.5 mA 7.4 7.5 7 0.4 % 7.35 7. ...
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... ML4800 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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... RMS over, to limit power dissipation of the circuit components under heavy brownout conditions). The relationship between V and gain is called K, and is RMS illustrated in the Typical Performance Characteristics. 3. The output of the voltage error amplifier, VEAO. The gain modulator responds linearly to variations in this voltage. ML4800 7 ...
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... ML4800 Current Error Amplier 16 VEAO V FB VEA IEA 15 – 1. – 2 GAIN V RMS MODULATOR 4 1.6k I SENSE 3 RAMP Cycle-By-Cycle Current Limiter TriFault Detect Overvoltage Protection 1 IEAO TRI-FAULT 0.5V + – 2.75V + – –1V PFC I LIMIT OSCILLATOR Figure 1. PFC Section Block Diagram PRODUCT SPECIFICATION ...
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... VEAO V FB VEA 15 – 2. GAIN V RMS MODULATOR 4 I SENSE 3 Figure 2. Compensation Network Connections for the Voltage and Current Error Amplifiers REV. 1.0.5 9/25/01 V REF 1 IEAO IEA + + – – Figure 3. External Component Connections BIAS R BIAS V CC 0.22 F 15V CERAMIC ML4800 ZENER GND ML4800 CC 9 ...
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... ML4800 Oscillator (RAMP 1) PWM SECTION Pulse Width Modulator 10 PRODUCT SPECIFICATION PWM Current Limit V OK Comparator IN PWM Control (RAMP 2) Soft Start REV. 1.0.5 9/25/01 ...
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... PRODUCT SPECIFICATION Generating VIN DC REF – RAMP OSC CLK U4 Figure 4. Typical Trailing Edge Control Scheme REV. 1.0.5 9/25/01 SW2 SW1 C1 RAMP VEAO DFF + VSW1 R Q – CLK ML4800 TIME TIME 11 ...
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... ML4800 Leading/Trailing Modulation VIN – REF RAMP OSC CLK U4 Figure 5. Typical Leading Edge Control Scheme 12 Typical Applications SW2 SW1 C1 RAMP VEAO DFF CMP + VSW1 R Q – CLK PRODUCT SPECIFICATION VEAO TIME TIME REV. 1.0.5 9/25/01 ...
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... PRODUCT SPECIFICATION Figure 6. 100W Power Factor Corrected Power Supply, Designed Using Micro Linear Application Note 33 REV. 1.0.5 9/25/01 ML4800 13 ...
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... Part Number ML4800CP ML4800CS ML4800IP ML4800IS 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; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS ...