FA5502PM Fuji Electric holdings CO.,Ltd, FA5502PM Datasheet

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FA5502P/M FUJI Power Supply Control IC Power Factor Correction FA5502P/M Quality is our message Quality is our message Quality is our message Quality is our message Application Note 1 June `02 Fuji Electric Co., Ltd. Matsumoto Factory ...

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FA5502P/M 1.This Data Book contains the product specifications, characteristics, data, materials, and structures as of June 2002. The contents are subject to change without notice for specification changes or other reasons. When using a product listed in this Data Book, ...

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FA5502P/M CONTENTS 1. Description 2. Features 3. Outline 4. Block diagram 5. Pin assignment 6. Ratings and characteristics 7. Characteristic curves 8. Description of each circuit 9. Design advice 10. Example of application circuit Note • Parts tolerance and characteristics ...

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FA5502P/M 1. Description FA5502P control IC for a power factor correction system. This IC uses a CMOS device with high dielectric strength (30V) to implement low power consumption. This IC uses the average current control system to ensure ...

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FA5502P/M 4. Block diagram CT(15) SYNC (14) OSC 15k 4.85k 0.39V S OCP.COMP IDET(16) 5. Pin assignment Pin No. Symbol Current 1 IFB output Inverting input to current 2 IIN- error amplifier Multiplier input 3 VDET Overvoltage ...

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FA5502P/M 6. Ratings and characteristics The contents are subject to change without notice. When using a product, be sure to obtain the latest specifications. (1) Absolute maximum ratings Item Supply VC pin Voltage VCC pin Low impedance source (Icc>15mA) VCC ...

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FA5502P/M (3) Electrical Characteristics Reference voltage section (REF pin) Item Symbol Output voltage V REF Line regulation Vrdv Load regulation Vrdi Temperature stability Vrd T Oscillator section (CT, SYNC pin) Item Symbol Oscillation frequency f OSC Voltage stability fdv Temperature ...

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FA5502P/M Current error amplifier section (IIN-, IFB, IDET pin) Item Symbol Input threshold voltage V THIDET Input bias current I BC Open loop gain Avc V OC+ Output voltage V OC- Output source current I OC+ Output sink current I ...

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FA5502P/M 7. Characteristic curves (Unless otherwise specified, Vcc=Vc=18V, Ta=25°C, C Oscillation frequency (fosc) vs. timing resistor ( 100 Oscillation frequency(fosc) vs. junction temperature(Tj -50 ...

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FA5502P/M Multiplier input voltage(V output voltage(V ) IIN- V VFB 1.4 1.2 1.0 V =2.9V VFB 0.8 V VFB 0.6 0.4 0.2 0 (V) VDET Voltage error amplifier reference voltage(Vr) vs. supply voltage(Vcc) 1.554 1.552 1.550 1.548 ...

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FA5502P/M ON/OFF control circuit ON threshold voltage(V THON junction temperature(Tj) 4.5 4.0 3.5 3.0 2.5 2.0 - (°C) L-level output voltage(V supply voltage(Vcc) I =100mA OL 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0. ...

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FA5502P/M Supply current(Icc) vs. supply voltage(Vcc) 16 ON/OFF pin: 14 pull up to Vcc Vcc (V) Operating-state supply current(Iccop) vs. junction temperature(Tj) 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 ...

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FA5502P/M 8. Description of each circuit (1) Oscillator section The oscillator generates sawtooth between 0.3V and 3.4V by charging and discharging capacitor. Fig.1 shows the connection. The oscillation frequency is determined by CT and R (see characteristics curve). The oscillator ...

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FA5502P/M (2) Voltage error amplifier and overvoltage limiting circuit ER.AMP is an error amplifier which constitutes a voltage feedback loop for keeping the output voltage constant. The non-inverting input connected to reference voltage Vr of 1.55V (typ.). Fig.6 shows the ...

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FA5502P Fig.8 Voltage gain of CUR.AMP (4) PWM comparator Fig.9 shows the configuration of PWM comparator. Oscillator output V and current error amplifier output CT V are compared. While V IFB comparator output goes High and OUT pin ...

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FA5502P/M (6) ON/OFF control circuit Fig.12 shows the configuration of the ON/OFF control circuit. The ON/OFF control circuit consists of a comparator with hysteresis. To turn the IC from OFF mode to operating mode, pull up the ON/OFF pin voltage ...

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FA5502P/M Without compensation full load no-load offset current 0 1/2 of line frequency With compensation full load result of compensation no-load 0 1/2 of line frequency Without compensation With compensation 0 PFC output power Fig.14 Operation outline of compensation circuit ...

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FA5502P/M 9. Design advice (1) Vcc circuit Vcc voltage can be supplied from an auxiliary winding of the inductor. An example circuit is shown in Fig.15. L Vac (sub VCC 7 FA5502 GND Fig.15 Vcc ...

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FA5502P/M (3) Designing a boost converter Fig.19 shows a basic circuit of boost converter used as an PFC converter. The following describes how to determine each values of the circuit Vin Rs Fig.19 Boost converter circuit (3-1) ...

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FA5502P/M (4) Output overvoltage at light load A compensation circuit for light load is incorporated for preventing an overvoltage when light or no load. Though, according to the condition, this circuit may not compensate enough and overvoltage may occur. To ...

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FA5502P/M (7) Prevention of intermittent switching of low frequency An intermittent switching below 10 Hz may occur in some application. It may be avoided by the following methods. They are given as typical preventions of intermittent switching and may not ...

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FA5502P/M GND wiring so as not to generate a common impedance with other wires. (11-5) VCC pin A noise applied to VCC pin may cause a malfunction. To suppress this noise, connect a capacitor near VCC pin even if IC ...

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FA5502P/M 10. Example of application circuit D2-D5 ERD03- C11 85 - 264V 0.1µF ON/OFF Vcc 18V GND Note This application circuit exemplifies the use of IC for your reference only. Parts tolerance, parts characteristics, influence ...