ISL8843 Intersil Corporation, ISL8843 Datasheet
ISL8843
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ISL8843 Summary of contents
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... Data Sheet Industry Standard Single-Ended Current Mode PWM Controller The ISL8843 is an industry standard drop-in replacement for the popular 28C43 and 18C43 PWM controllers suitable for a wide range of power conversion applications including boost, flyback, and isolated output configurations. Its fast signal propagation and output switching characteristics make this an ideal product for existing and new designs ...
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Functional Block Diagram V DD START/STOP UV COMPARATOR + - + - GND A 2.5V A=0 Total = 1.15V ERROR AMPLIFIER COMP VREF 100K 2.9V 1.0V 150K OSCILLATOR COMPARATOR < 10nS - RTCT + CLOCK ...
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... Typical Application - 48V Input Dual Output Flyback VIN+ R1 36-75V C1 VIN VR1 CR2 C5 CR6 R22 R27 U4 R26 COMP VREF CS FB RTCT ISL8843 R10 CR1 C8 CR5 C21 + C15 + C16 T1 R21 CR4 + C22 + C17 C20 C19 R16 R17 R18 C6 U2 R19 C14 ...
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... ISL8843MxZ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-55°C to 125°C Supply Voltage Range (Typical) ISL8843 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9V - 30V CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. ...
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... Electrical Specifications ISL8843A - Typical Application schematic. V are at T PARAMETER FB Input Bias Current COMP Sink Current COMP Source Current COMP VOH COMP VOL PSRR OSCILLATOR Frequency Accuracy Frequency Variation with V DD Temperature Stability Amplitude, Peak to Peak RTCT Discharge Voltage (Valley Voltage) Discharge Current ...
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... This is the V current consumed when the device is active but not switching. Does not include gate drive current Guaranteed by design, not 100% tested in production. 6 ISL8843 - Recommended operating conditions unless otherwise noted. Refer to Block Diagram and = 15V 10kΩ 3.3nF 25°C (Continued) ...
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... • ISL8843 80 100 120 140 FIGURE 2. REFERENCE VOLTAGE vs TEMPERATURE 3 1•10 100 100 120 140 1 The formulae have increased error at higher frequencies due to propagation delays. Figure 4 may be used as a guideline in selecting the capacitor and resistor values required for a given frequency ...
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... GND with a 0.1µF to 3.3µF capacitor to filter this output as needed. Functional Description Features The ISL8843 current mode PWM makes an ideal choice for low-cost flyback and forward topology applications. With its greatly improved performance over industry standard parts the obvious choice for new designs or existing designs which require updating ...
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... Substituting Equations 12 and 13 into Equation 14 and solving for (EQ. 9) Adding slope compensation is accomplished in the ISL8843 using an external buffer transistor and the RTCT signal. A (EQ. 10) typical application sums the buffered RTCT signal with the current sense feedback and applies the result to the CS pin as shown in Figure 6. ...
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... V bypassed directly to GND with good high frequency capacitors. References [1] Ridley, R., “A New Continuous-Time Model for Current Mode Control”, IEEE Transactions on Power Electronics, Vol. 6, No. 2, April 1991. 10 ISL8843 , using Equation 15 using Equation 18. should be DD FN9238.1 January 3, 2006 ...
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... The lead width “B”, as measured 0.36mm (0.014 inch) or greater above the seating plane, shall not exceed a maximum value of 0.61mm (0.024 inch). 10. Controlling dimension: MILLIMETER. Converted inch dimensions are not necessarily exact. 11 ISL8843 M8.15 (JEDEC MS-012-AA ISSUE C) 8 LEAD NARROW BODY SMALL OUTLINE PLASTIC PACKAGE M B ...
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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 12 ISL8843 M8.118 (JEDEC MO-187AA) 8 LEAD MINI SMALL OUTLINE PLASTIC PACKAGE SYMBOL ...