TK75003D TOKO, Inc, TK75003D Datasheet
TK75003D
Related parts for TK75003D
TK75003D Summary of contents
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... The reduced charging current causes no more than a one-third reduction in switching frequency, effectively preventing short-circuit current runaway. ORDERING INFORMATION TK75003D TEMP. CODE (OPTIONAL) I: -40 to +85 C January 1999 TOKO, Inc. APPLICATIONS Power Factor Correction Converters ...
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... ° January 1999 TOKO, Inc ...
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... Note 1: Power dissipation is 825 mW when mounted. Derate at 6.6 mW/ C for operation above 25 C. Note 2: For temperature dependence refer to "Slope Compensation Peak Current vs. Temperature" graph. Note 3: The UVLO "on" voltage is guaranteed always to be below the internal clamp voltage. Note 4: Guaranteed by design; not 100% tested. January 1999 TOKO, Inc 800 pF 1000 pF, T ...
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... C DRV = DRV = 500 DRV = 120 0 400 800 FREQUENCY (kHz 4.7 µF 1 µF VS. CURRENT CONTROL REFERENCE TEMPERATURE VS. 1.00 0.98 0.96 0.94 0.92 0.90 10000 -40 0 TEMPERATURE ( C) FREQUENCY REDUCTION RATIO VS. TEMPERATURE -40 0 1200 1600 TEMPERATURE ( C) January 1999 TOKO, Inc 120 VS 120 ...
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... TYPICAL PERFORMANCE CHARACTERISTICS (CONT.) SLOPE COMPENSATION RAMP GND 600 800 pF 450 300 150 TIME (µs) January 1999 TOKO, Inc. i SC(PK) i SC(PK - VL) i SC(VL) 20 TK75003 Page 5 ...
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... The Undervoltage Lockout (UVLO) feature with hysteresis minimizes the start-up current which allows a low-power boot-strap technique to be used for the housekeeping power. The duty ratio of the TK75003 is limited to approximately 88% by the time required to discharge the timing ramp. January 1999 TOKO, Inc. ...
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... January 1999 TOKO, Inc. PIN DESCRIPTIONS current with a peak value of about 200 A. The error signal is needed for stabilizing the output voltage or current. The ...
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... T)] + [(V AUX 1 D3 AUX 1 can be calculated as follows OUT OVERSHOOT is the additional voltage appearing OVERSHOOT can be calculated as follows OUT D2 January 1999 TOKO, Inc. is the AUX . The T)]) 2 D3 AUX ...
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... R yields: AUX R = 20.6 AUX Rounding the result to the nearest 5% standard value gives AUX January 1999 TOKO, Inc. DESIGN CONSIDERATIONS (CONT.) can be calculated as OVERSHOOT and T is the 2 FIGURE 1: TK75003 IN A FLYBACK POWER SUPPLY or the voltage V AUX AUX (a) SCHEMATIC ...
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... AUX + DRV PWM RAMP FB GND TL431 (a) CYCLE-BY-CYCLE CURRENT LIMIT (b) VOLTAGE AT FEEDBACK PIN keeps the timing pin at ground potential 1 is turned off. The off-time 1 January 1999 TOKO, Inc 0.98 V FEEDBACK VOLTAGE 0 (b) 1 ...
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... V FEEDBACK VOLTAGE LEVEL FB FIGURE 6: TIMING PIN AND FEEDBACK PIN VOLTAGES WITH CONSTANT OFF-TIME CURRENT- MODE CONTROL January 1999 TOKO, Inc. TK75003 IN NON-ISOLATED APPLICATIONS Although the IC was intended for off-line power-supply applications with the voltage-error amplifier at the isolated + V OUT output easy and economical to use the device in non- isolated applications, too ...
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... I(MIN)(PK EFF = 107 OUT (at peak of minimum line voltage 1.95 A L1(PK) I I(MIN)(PK) (Note 1 4.312 kohms 7 MAX CCD SC(PK) January 1999 TOKO, Inc 100 kHz 0.88 MAX I = 200 A SC(PK 0.98 V CCD = 120 0.684 : 0.33 A ...
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... 250 V 10 600 V, 1 85-265 VAC 0.1 µF FIGURE 9: BOOST POWER FACTOR CORRECTOR APPLICATION CIRCUIT January 1999 TOKO, Inc. (Note 2 0.201 ohms L1(PK 2 220 ...
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... Visit our Internet site at http://www.tokoam.com The information furnished by TOKO, Inc. is believed to be accurate and reliable. However, TOKO reserves the right to make changes or improvements in the design, specification or manufacture of its products without further notice. TOKO does not assume any liability arising from the application or use of any product or circuit described herein, nor for any infringements of patents or other rights of third parties which may result from the use of its products ...