KA7541 Fairchild Semiconductor, KA7541 Datasheet
KA7541
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KA7541 Summary of contents
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... Fairchild Semiconductor Corporation www.fairchildsemi.com Descriptions The KA7541 provides simple and high performance electronic ballast control functions. KA7541 is optimized for electronic ballast requiring a minimum board area, reduced component count and low power dissipation. Internal soft start circuitry eliminates the need for an external soft start PTC resistor ...
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... KA7541 Internal Block Diagram 0. 180pF 3V 8Ict 1V 30k 3pF 22k 2k 40k Ldet 4 5pF Absolute Maximum Ratings Parameter Supply voltage Peak drive output current Drive output clamping diodes V > < 0 Soft start, and no lamp detection input voltage Operating temperature range Storage temperature range ...
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... The output of a high-current power driver capable of driving the gate of a power 6 OUT 2 MOSFET The output of a high-current power driver capable of driving the gate of a power 7 OUT 1 MOSFET The logic and control power supply connection Ldet 4 (Top View) Pin Function Descrition KA7541 OUT1 7 OUT2 6 GND 5 3 ...
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... KA7541 Electrical Characteristics Unless otherwise specified, for typical values Vcc=14V, Ta=25 o -25 Ta 125 temperature range with C Parameter UNDER VOLTAGE LOCK OUT SECTION Start threshold voltage UVLO hysteresis SUPPLY CURRENT SECTION Start up supply current Operating supply current Dynamic operating supply current REFERENCE SECTION ...
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... The rising slope and falling slope of the triangular waveform are as following. Rising slope Falling slope For example, when the timing capacitor is 180pF, Tch = 6.69 Tdis = 0.956 2 Vin ac_max 2 Vcc – ------------------------------------------------------------------------ P 0.5W = RSt Vin ac_max 2 Vcc – 260K St Q1 Rectifier Output Q2 Cq2 Rst (Pin Cst Figure 1. Start up circuit KA7541 260K R 440K ...
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... Soft Start The switching frequency is linearly decreasing from the pre-heating frequency to the normal switching frequency. In KA7541, the initial pre-heating frequency can be adjusted depending on the types of the lamps used. During the pre-heating mode, a sixth of the soft start current (I timing capacitor charging current (50 A). The rising and falling slope of the triangular waveform are increased due to this added current ...
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... When in normal mode the average voltage of the V3 is the half of the dc link voltage (Vdd). So, in order to make stable start condition, the resistors are designed to make the voltage the half of the dc link voltage. fsw tss 680K + + 15K 2 200V R 3 KA7541 7 ...
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... KA7541 8 DC Link Voltage (Vdd Rfilament Rfilament R2 Rfilament Rfilament R3 To pin # Figure 4. Lamp detection resistor network V3 ...
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... AC DC Full-wave Rectified Output NTC TNR F1 AC INPUT To PFC Output To full-wave rectified voltage R12 C10 FAN7527 R14 R10 Q3 C14 R11 C21 D8 KA7541 R17 R18 R13 C11 C12 C13 R19 KA7541 PFC Output R15 C17 C19 C15 L3 L4 C18 C20 C16 D7 R16 9 ...
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... KA7541 Component Listing Part number R1 R2 R3, 12 R4, 13 R5, 10 R14 R15, 16 R17, 18 R19 C1 C11, 21 C12 C13 C14 C15, 16 C17, 18, 19 D7, 8 ZD1 TNR NTC 10 Value 2.7M 18k 150k 22k 47 3.3 0.2 1.2M 103 Variable resistor 180k 330k ...
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... Mechanical Dimensions Package #1 #4 6.00 0.236 3.95 0.156 0.50 0.20 0.020 0.008 8-SOP 1.55 0.20 0.061 0.008 #8 #5 0.30 1.80 MAX 0.012 0.071 0.20 0.008 5.72 0.225 Dimensions in millimeters 0.1~0.25 MIN 0.004~0.001 KA7541 11 ...
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... KA7541 Mechanical Dimensions Package 6.40 0.20 0.252 0.008 # 7.62 0.300 12 (Continued) Dimensions in millimeters 8-DIP 5.08 MAX 0.200 3.40 0.20 0.013 0.134 0.008 3.30 0.30 0.130 0.012 0.33 MIN ...
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... Ordering Information Product Number Package KA7541 8-DIP KA7541D 8-SOP Operating Temperature - +125 C KA7541 13 ...
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... KA7541 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. ...