FA551x ETC, FA551x Datasheet
FA551x
Related parts for FA551x
FA551x Summary of contents
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... FA5510P (N), FA5511P (N) FA5514P (N), FA5515P (N) Description The FA551X series are the PWM type switching power supply control ICs that can directly drive power MOSFET. These ICs use a CMOS device with high dielectric strength (30V) to implement low power consumption. These ICs contain many function in a small 8-pin package ...
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... FA551X Absolute maximum ratings I tem Supply Voltage Low impedance source (I Internal zener clamp (I Output peak current FB pin input voltage IS pin input voltage REF pin source current CS pin sink current Total power dissipation (Ta=25˚C) Ambient temperature Maximum junction temperature Storage temperature Note: There are cases where the IC cannot output the rating current depending on Vcc voltage or temperature. ...
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... FA5310/14 FA5311/15 Min. Typ. Max. Min. Typ. Max. –5.2 –3.2 –7.2 –5.2 –3.2 0.90 1.0 0.90 1.0 1.92 2.40 MAX Min. Typ. Max. –7.2 –5.2 –3.2 0.8 0.93 0.50 0.68 0.12 FA551X Unit mV/˚C Unit kHz % %/˚C Unit Unit µA ns Unit µ Unit µ ...
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... FA551X Latch-mode cutoff circuit section (CS pin) Item Sink current (CS pin) Cutoff threshold voltage (CS pin) Hysteresis voltage Overload cutoff circuit section (FB pin) Item Overload threshold voltage (FB pin) Overvoltage cutoff circuit section (VCC pin) Item Overvoltage threshold voltage (VCC pin) Cutoff operating supply current (VCC pin) ...
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... Maximum duty cycle (D T FA5511/ 100 1000 67 ) vs. supply voltage (V OSC Vcc (V) ) vs. FB pin voltage ( ( vs. timing resitor resistance (R MAX 1 10 100 FA551X ) 1000 5 ...
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... FA551X Maximum duty cycle (D ) vs. junction temperature (Tj) MAX FA5510/14 47 46.8 46.6 46.4 46.2 46 45.8 45.6 45.4 45 (˚C) IS (+) pin current (I ) vs. IS (+) pin voltage (V IS (+) FA5510/11 0 -0.05 -0.1 -0.15 -0.2 -0.25 -0.3 -0.35 -0 (V) IS (+) CS pin current (I ) vs. CS pin voltage (V CS FB=open - ( Maximum duty cycle (D ...
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... –100mA O 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1 0.9 0 (V) CC 100 150 ) vs. UVLO ON-to-OFF threshold voltage (V CCON junction temperature (Tj) 9.1 9.05 8.95 8.9 100 150 ) L-level output voltage ( =100mA O 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0 vs. CCOFF 9 - 100 Tj (˚C) ) vs. supply voltage ( (V) CC FA551X 150 ) ...
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... FA551X Operating state supply current (I CCOP supply voltage ( 1.8 1.7 FB=0V 1.6 1.5 1.4 1.3 1.2 1.1 FB=Open 1 0.9 0 (V) CC OFF state supply current (I ) vs. supply voltage (V CCOFF 3000 2500 2000 1500 1000 500 (V) CC Latch mode supply current (I ) vs. supply voltage (V CCL 3000 2500 2000 ...
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... CS pin voltage PWM comparator output OUT pin voltage under the OSC Fig. 1 Oscillator R =Small R =Large Fig. 2 Oscillator output DT voltage FB pin voltage CS pin voltage PWM comparator Oscillator output output Fig. 3 PWM comparator Fig. 4 PWM comparator timing chart FA551X (4.0V) 9 ...
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... FA551X 3. CS pin circuit As shown in Figure 5, capacitor Cs is connected to the CS pin. The CS pin voltage varies depending on the charging voltage of this capacitor Cs. When the power is turned on, the constant current source (5.2µA) begins to charge capacitor. Accordingly, the CS pin voltage rises as shown in Figure 6. The CS pin voltage is connected to the PWM comparator, which is characterized to make output based on the lowest of input voltages ...
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... C1 5V VCC 7 5.2 A ENB C2 5V REF 8.5/7.9V PWM FB 2 DMAX OSC 1 RT External output ON/OFF control circuit (4V) CS pin voltage DT voltage FB pin voltage Oscillator output OFF ON mode OFF mode Output ON/OFF control circuit timing chart FA551X VCC 6 UVLO Output circuit 11 ...
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... FA551X 4. Overcurrent limiting circuit The overcurrent limiting circuit detects the peak value of every drain current pulse (pulse by pulse method) of the main switching MOSFET to limit the overcurrent. The detection threshold voltage is +0.24V for FA5510/11 or –0.17V for FA5514/15 with respect to the ground as shown in Figure 13 and Figure 14 ...
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... Note that the output current causes loss of the output stage. The total loss caused by the operating current and the output current should be within the ratings in actual circuit. FA551X 13 ...
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... IC via the start-up resistor is stopped when AC input is shut down. Therefore, after latch mode operation, shutting the AC input down resets the latch mode in a very short period of time INPUT ~ VCC 6 MOSFET FA551X 5 OUT Rs Fig. 18 Startup circuit (1) T1 ...
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... OUT Fig. 19 Startup circuit (2) Vcc UVLO ON Vcc must not drop to UVLO OFF. UVLO OFF Auxiliary winding voltage Time t Fig. 20 Vcc voltage at startup with a adequate capacitor Vcc UVLO ON UVLO OFF Fig. 21 Vcc voltage at startup with a inadequate capacitor FA551X T1 D1 MOSFET Rs Time t 15 ...
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... ZD maintains the Vcc voltage 32V or less and protects the IC. 16 FA551X Fig. 22 VCC FA551X Fig Fig. 24 Independent setting of soft start period and OFF latch deley R1 D1 VCC C2 6 Startup circuit ( Startup circuit ( FA551X 4 GND ...
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... CS 8 VCC 6 Fig. 26 Overvoltage shutdown circuit (2) 6 VCC Fig. 27 Overvoltage shutdown circuit (3) 5 PC1 FA551X OUT PC1 Shunt C4 regulator Fig pin circuit (1) 5 FA551X OUT GND PC1 C4 Fig pin circuit (2) FA551X Vout Vout 17 ...
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... FA5510/11 that uses positive polarity for overcurrent detection VCC REF FA551X 2 n3 GND Fig. 30 Simple voltage control circuit FA551X GND 10k C4 Fig. 31 Disabling overload shutdown function input ~ – ...
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... Rg1 and Rg2 restrict the current when the MOSFET is turned on, and only Rg1 restricts the current when it is turned off. OUT FA551X 5 4 SBD GND Fig. 33 Protection of OUT pin against the negative voltage Rg2 Rg1 5 FA551X OUT Fig. 34 Gate circuit FA551X 19 ...
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... FA551X 15. Loss calculation IC loss must be confirmed to use the IC within the ratings. Since it is hard to directly measure IC loss, some examples of calculating approximate IC loss are given below. 15.1 Calculation example 1 Suppose the supply voltage is Vcc, IC current consumption is lccop, the total gate charge of the power MOSFET is Qg, and the switching frequency is f ...
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... F IC2 R203 2.2k C113 2200p D201 L201 YG902C C201 C202 2200 F 470 F C204 0.022 F R207 2.4k PC1 R206 1k R205 33k C203 0.1 F IC2 R203 2.2k FA551X +24V 0 to 8.4A C207 0.1 F GND C204 0.022 F C206 0.1 F +24V 0 to 1.46A (Peak:2.71A) GND R201 18k R202 1k 21 ...
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... FA551X FA5514 C103 C114 144V AC 250V/5A 0.47 F 4700p D1 R101 510K R102 510K L2 C102 C104 D3SBA60 0.22 F 4700p R103 100k FG R104 100k R107 680 IC1 FA5514 C109 0.22 F R106 33 FA5515 80 to C101 C103 264V AC TH1 DB 0.22 F 470p R101 5D11 510K R102 430K L1 C104 C102 ...