FA5626 FUJI [Fuji Electric], FA5626 Datasheet
FA5626
Related parts for FA5626
FA5626 Summary of contents
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... Fuji Switching Power Supply Control IC Green Mode PWM IC Application Note Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 FA5626 http://www.fujielectric.co.jp/products/semiconductor/ 1 April.-2011 Fuji Electric Co., Ltd. ...
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... Fuji Electric Co.,Ltd. and its sales agents shall not be liable for any damage that is caused by a customer who does not follow the instructions in this cautionary statement. Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Caution - Communication equipment (Pin) - Home appliance - Personal equipment - Communication equipment for trunk line - Various equipment for the safety ...
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... Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Contents ・・・・・・・・・・・・・・・・・ ・・・・・・・・・・・・・・・・・ ...
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... Overview FA5626 is a current mode type switching power supply control IC possible to drive a power MOSFET directly. Despite of a small package with 8 pins, it has a lot of functions and it is best suited for power saving at the light load and decreasing external parts. Moreover it enables to realize a reduced space and a high cost-performance power supply. ...
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... Block diagram FA5626 (Overload protection : Auto recovery type) Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 http://www.fujielectric.co.jp/products/semiconductor/ 5 ...
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... IS 4 GND 5 OUT 6 VCC （NC） Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Pin function I/O I External latch signal input. (Connect capacitor LAT and GND) I Feedback control signal input I Current Limiter Input (Negative voltage sense) － IC Ground O Output － Power Supply (Connect capacitor between VCC and GND) － ...
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... Power dissipation (Ta=25°C) Maximum junction temperature in operation Storage temperature *1 Never exceed power dissipation Pd. ○Maximum dissipation curve(SOP) 400mW 0 -30 Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Symbol VLAT ILAT VFB IFB VIS IIS VOUT IOH IOL VVCC At input plus voltage IVCC ...
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... Operating time of minimum ON pulse *1 Start soft-start LAT pin voltage *1 Finish soft-start LAT pin voltage After soft-start LAT pin voltage *2-1：Start and Re-start of after VCCon or Brown-in Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Symbol MIN. TYP. VCC 12 18 － VVH 100 － RVH 2.2 CLAT ...
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... Symbol Over load detection VthOLP threshold voltage *1 Over load detection Delay TdOLP time *1 Waiting time of auto restart TdOLP2 *1 Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Condition Fosc VFB=2V VCC=12 to 24V Fdv VFB=2V Tj=-30 to 125°C ⊿Fdt VFB=2V Fm VFB=2V VFB=2V VFB=Decreasing VLAT=1.8V *3-1 Vfbm VFB=Decreasing VLAT=1 ...
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... Item Symbol ICCop1 Operating-state supply current ICCop2 Supply current at Brownout or ICCbo OLP Latch mode supply current ICClat Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Condition AvIS VFB=2V to 1.5V VFB= Full & Half-wave VthOLP, rectification VVH> VHVTH2 VFB= Full & Half-wave VthOLP, rectification VVH< ...
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... Threshold voltage level at Brown-in (VH pin) Brown-out delay time *1 TpdBO VCCBH VCC voltage at Brown-out VCCBL VCCLHH VCC voltage at Latch VCCLH VCCLL Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Condition VH=450V,VFB=0V VH=120V, VCC=0V,VFB=0V VH=120V,VCC=2 to 8V, VFB=0V VH=120V,VCC=11V, VFB=0V VH=120V,VCC=16V, VFB=0V VCC=16V, Ipre1 VH=120V,VFB=0V VCC=11V, ...
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... Junction Temparature Tj ( ℃ pin voltage at frequency drop started (Vfbm) vs. Junction Temparature(Tj) 2.1 2 1.9 1.8 1.7 1.6 1.5 - Junction Temparature Tj [ ℃ ] Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 -250 -255 -260 -265 -270 -50 100 150 320 310 300 290 280 270 260 250 100 150 ...
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... Junction Temparature(Tj) 27.0 26.5 26.0 25.5 25.0 - Junction Temparature Tj ( ℃ pin input current (IHstb) vs. Junction Temparature(Tj - Junction Temparature Tj ( ℃ ) Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 -10 -11 -12 -13 -14 -50 100 150 120 110 100 90 80 -50 100 150 ...
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... Junction Temparature Tj ( ℃ ) Brown-in threshold voltage (VthBI) vs. Junction Temparature(Tj) 108 107 106 105 104 103 102 - Junction Temparature Tj ( ℃ ) Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Operating-state supply current (ICCop2) 1.6 FB=2V 1.5 1.4 1.3 1.2 1.1 100 150 -50 IS pin maximum input threshold voltage (VthIS1) -0.47 -0.48 -0.49 -0.5 -0.51 -0.52 -0 ...
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... If the overvoltage protection is actuated, causing the IC to enter the latch mode, then the startup circuit is subjected to ON/OFF control to maintain the VCC voltage within the 12V to 13V (typ) range. (P.19 8-(7) over voltage protection) Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 C1 Startup R VH circuit VH current ...
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... Frequency diffusion（Spread spectrum） FA5626 perform frequency modulation of ± 4.5 kHz for switching frequency 65 kHz (during the operation in which the FB pin voltage is higher than 1.55 V.). This function enables more noise energy of the switching to disperse compared to the case with fixed frequency and obtains a conduction EMI reduction effect ...
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... This minimum ON width function eliminates the need of a Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 noise filter for the IS pin in principle. The minimum ON width is usually set to 1250ns or 1700ns (typ) in normal operations, and to 280ns (typ) at startup or rebooting to prevent the transient MOSFET drain voltage from surging ...
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... Overload protection circuit FA5626 integrates auto-restart mode overload protection function. Fig. 10 shows the circuit block diagram and Fig. 11 shows the protection timing chart. When output current increases by the overload, MOSFET current is limited by the maximum threshold voltage (-0.5V typ pin. The output voltage is drops because of current limit and FB pin voltage rises. When FB pin voltage is over the threshold voltage (VthOLP), overload is detected ...
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... Short circuit detection FA5626 has a protection function for output short-circuit without delay time. If output of PSU is shorted, FB pin voltage goes high. In addition, Vcc voltage drops because auxiliary winding voltage almost zero. IC stops switching operation at the instance when IC detects that FB pin voltage exceeds overload detection voltage and Vcc drops below Vthshort (11V typ ...
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... FA5626 has a brown-out function that stops switching operation when the AC input voltage drops below normal operating voltage.Fig.14 shows input voltage waveform of VH pin. When VH pin voltage reached brown-in threshold voltage (DC 105V typ.), switching operation is started. When VH pin voltage drops below brown-out threshold voltage for longer than delay timer, brown-out function stops switching operation ...
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... Approximate effective soft start time (period(3)) can be calculated using the following expression. Tss = 0.4×CLAT / Ilat Tss :Soft-start time [sec] CLAT: Capacitor connected to LAT pin [uF] Ilat :LAT pin source current [uA] (70uA typ.) (4) PWM operation start Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Fig.16 Soft-start operation http://www.fujielectric.co.jp/products/semiconductor/ 21 ...
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... Fig.18 VCC pin voltage at startup (when capacitance is too small) Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 (2) VCC hold time To prevent the VCC pin voltage from decreasing to lower than the UVLO OFF threshold voltage due to sudden load change and other reasons, it may be desirable that the capacitance of the capacitor to be connected to the VCC pin be made larger ...
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... C3 Fig.24 FB pin circuit configuration Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 (6) Current sensing unit As described in 8-(4) One-shot circuit, the minimum ON width is set for this IC to minimize malfunction due to surge current that occurs when the power MOSFET is turned on. However, if the surge current that occurs at the time of power ON is large, or noise is applied externally at the time of power ON, malfunction might occur ...
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... April-2011 FA5626 Fig.28 Overload detection level on input voltage (2) (8) Input power improvement at light load FA5626 can reduce the standby power by lowering the oscillation frequency at light load. However, in some case internal function of IC may not reduce standby power enough. In such a case, connect resistor R8 between OUT pin and IS pin. If resistor k ...
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... IC, etc. Please decide Rs value after test in the actual circuit. Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 Case where input voltage dependency reducing resistor R9 is connected (as in Fig. 27 input voltage dependency reducing resistor is connected, IS pin voltage changes as shown in Fig. 31. ...
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... Furthermore, assuming that Tj = 25C, VCC = 18V, and Qg = 80nC, and based on IHrun=100uA (typ.) ICCop1=1.4mA (typ.) fsw=65kHz (typ.) the loss of the IC having standard characteristics can be calculated as follows: Pd≒18V × (1.4mA + 80nC × 65kHz) + 45V × 100uA ≒ 123 mW Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 http://www.fujielectric.co.jp/products/semiconductor/ 26 ...
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... VH Pin is connected to near by diode bridge (DS1) to avoid VH Pin’s surge voltage it happens by change of startup current when startup circuit repeats on-off operating. 3) Please connect the diode and resistance with the series between the bulk capacitor or the rectified AC line so that VH Pin must not become a negative voltage. Fuji Electric Co., Ltd. AN-071E Rev.1.2 April-2011 FA5626 C6 DS1 ...