SI9117 Vishay, SI9117 Datasheet
SI9117
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SI9117 Summary of contents
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... In addition to these mandatory design considerations, the Si9117 is easy to design with and compensate, and takes a minimum of board area to implement: an important benefit in high-volume/small-package applications such as set-top boxes and microcell base stations. ...
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... Si9117 Vishay Siliconix ABSOLUTE MAXIMUM RATINGS Voltages Referenced to − (Note: V < 0 Logic Input (SHUTDOWN, SYNC Linear Inputs (FEEDBACK, SENSE, SOFT-START Pre-Regulator Input Current (continuous Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... DRAIN Vishay Siliconix Limits a b Min Typ Max UVLO 8.8 9.1 9.4 0.1 0.25 0.7 0.18 0.28 0.4 = 100 kHz 1.8 2.5 = 500 kHz 3.7 4.5 1.035 1.16 1.30 105 130 2.8 0.5 0.21 1 1.6 0.5 = 25_C 0 25_C 0 50 10% 0 Si9117 a Unit www.vishay.com 3 ...
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... Si9117 Vishay Siliconix TYPICAL CHARACTERISTICS Output Frequency 1000 OSC 100 pF 150 pF 200 pF 100 10 10 100 R − Oscillator Resistance (k) OSC Supply Current vs. Supply Voltage 250 kHz OUT − Supply Voltage (V) CC Drain-Source On Resistance vs. Temperature 1.2 1.0 0.8 0.6 0.4 −50 − ...
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... Temperature (_C) J Document Number: 70027 S-40750—Rev. E, 19-Apr-04 −20 −40 −60 −80 −100 −120 −140 1000 4000 1050 1025 1000 975 950 50 75 100 Vishay Siliconix Reference Voltage vs. Temperature 4020 4010 4000 3990 3980 3970 3960 −50 − Si9117 75 100 www.vishay.com 5 ...
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... Part Number Si9117DY Si9117DY-T1 Si9117DY-T1—E3 Generates a 20-mA current source. IC turns or when capacitor is charged to 4.6 V. Sets the oscillator charging current. Use the “oscillator frequency vs. R section. Sets oscillator frequency. Use the “Oscillator frequency vs. R along with equations 1 and 2 in the Oscillator section of the Description of Operations. ...
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... C OSC I SENSE APPLICATIONS Description of Operation The Si9117 is a current mode PWM IC combined with an integrated 1-W 200-V MOSFET. Current mode operation offers the following advantages: D Cycle-by-cycle current limit protection D Simple loop compensation, eliminating the effect of output inductor D Excellent fast transient response due to inner control loop ...
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... During start-up, the Si9117 will begin operation as soon as the UVLO threshold is reached. Since the converter is de- signed to operate over a much higher range—for example, from V—then between 10 and 36 V input the output voltage will be out of regulation and undefined. In some ...
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... These can be prevented with the use of long soft-start times. The soft-start pin can also be used as a non-latching shutdown pin by connecting it to −V soft re-start. FBK NINV Soft- Start Si9117 Vishay Siliconix +OP − TL431 . This approach allows a shutdown with ...
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... In certain circumstances, such as current limiting, it may be desirable to change the frequency of the converter for a period of time to overcome current tails (see Figure 14 for further explanation). With the Si9117, this is easily done by adding or subtracting some current into the R D The charging current The voltage at the R ...
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... Open = Frequency Low 1 Current Change t Si9117 COMP OSC OSC SYNC V REF V− SENSE IC3 converters, where noise caused Si9117 C VCC www.vishay.com 11 ...
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... These spikes can confuse the PWM comparator into believing that an overload condition is present. In addition, rail the Si9117 uses a single pin (−Vin) for all the return current CC requirements, including the output driver result, the current pulse from the gate charge transfer into the MOSFET will appear on the sense pin and be filtered out ...
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... C transformer, through the MOSFET and Sense resistor, and back into should not be mixed with signals that are controlling a closed-loop, high-gain feedback system which is capable of regulating the output voltage to less than 1 mV. Si9117 Vishay Siliconix L V OUT iL ...
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... High minimum duty ratios will result in current tails and require rectifier oversizing to avoid destructive currents under overload conditions. The Si9117 has a sync-to-output delay of less than 70 ns, so the minimum duty cycle for operation at 500 kHz would 7%. This minimum should be considered when the short circuit current is determined ...
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... 6.8 kW FIGURE 15. Complete Schematic Diagram Vishay Siliconix 10 mH C14 6 R17 180 W R16 22 kW R14 1 kW TCMT1020 C12 100 pF IC3 C11 R18 IC4 TL431CLP R15 22 kW “Y” Grade Capacitor Typically 4.7 nF Si9117 J2 CON4 www.vishay.com 15 ...
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... Information contained herein is intended to provide a product description only. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Vishay's terms and conditions of sale for such products, Vishay assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale and/or use of Vishay products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right ...