isl9491 Intersil Corporation, isl9491 Datasheet
isl9491
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isl9491 Summary of contents
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... Single Output LNB Supply Voltage Regulator for Satellite Set-Top Box Applications ISL9491, ISL9491A These devices are designed for supplying power and control signals from advanced satellite set-top box (STB) modules to the low noise blocks (LNBs) of single antenna ports. Each device consists of a current-mode boost ...
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... This an open drain output to be pulled up to the logic high through a resistor. A low indicates that the output voltage is out of regulation. ILIMIT The ILIMIT is used to set the value of the output current limit from the linear. A resistor from ILIMIT to GND programs this limit. 2 ISL9491, ISL9491A FUNCTION at this pin for desired peak overcurrent value for the boost SC FN6531.0 October 13, 2009 ...
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... LOGIC SCHEME 1 GATE 4 PGND 3 ILIM1 CS AMP CS 2 VSW 14 VOUT 6 VSENSE 7 ON CHIP VCC 1 LDO UVLO SGND POR 8 SOFT-START 5 3 ISL9491, ISL9491A 9 10 OLF DCL PWM OC1 LOGIC Q CLK1 S OSCILLATOR OTF - ∑ SLOPE BAND GAP COMPENSATION REF VOLTAGE - VOLTAGE VREF1 VREF2 U AND L + FET - ...
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... The output voltage level for the desired polarization reception can be selected by means of the logic presented to VSET0 and VSET1 pins. R20 10kΩ C37 1µ VCC ILIMIT R23 TCAP ISL9491ER, or 10KΩ ISL9491AER 3 10 PGND VSET1 GATE VSET0 0 VBYPASS D12 C39 1µ ...
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... Electrical Specifications V T PARAMETER Operating Supply Voltage Range Supply Current (Ivcc current) UNDERVOLTAGE LOCKOUT Stop Threshold Start Threshold Output Voltage, ISL9491 Output Voltage, ISL9491A Line Regulation Load Regulation Output Overcurrent Threshold Internal Regulator Overcurrent Clamp 5 ISL9491, ISL9491A Thermal Information Thermal Resistance (Typical) QFN Package (Notes Maximum Junction Temperature (Note +150° ...
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... Tone Fall (Note 10) OUT CURRENT SENSE (CS PIN) Overcurrent Threshold BYPASS Voltage at BYPASS pin PWM Maximum Duty Cycle Minimum Pulse Width 6 ISL9491, ISL9491A = 12V -20°C to +85°C, unless otherwise noted. Typical values are +25°C. (Continued) A SYMBOL TEST CONDITIONS t Output Shorted to GND (Note 6) ...
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... TEST CONDITIONS f Boost switching frequency sw (Note 4) (Note 4) 22kHz 22kHz RETURNS TO NOMINAL VOUT ~1.5 PERIOD EXTERNAL TONE AFTER THE LAST EXTM RISING EDGE t = 5/10µs TYPICAL r t_ISL9491~68µs / t_ISL9491A)~34µs FIGURE 1. TONE WAVEFORM 0.5 0.6 0.7 TO FIGURE 3. SYSTEM EFFICIENCY (BOOST + LDO) FOR IN MIN TYP 380 440 - 130 ...
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... FIGURE 4. VLNB RISE TIME WITH TCAP = 0.22µF is 13ms FIGURE 6. BOOST SWITCH NODE AT 0A (DISCONTINUOUS) FIGURE 8. BOOST SWITCH NODE AT 300mA (CONTINUOUS MODE) 8 ISL9491, ISL9491A (Continued) FIGURE 5. VLNB RISE TIME WITH TCAP = 0.44µF is 32ms FIGURE 7. BOOST SWITCH NODE AT 100mA (PARTIAL CONTINUOUS) FIGURE 9. VLBNB TRANSITIONS FROM 13. ...
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... FIGURE 10. VLNB TRANSITIONS FROM 18.3V TO 13.3V FIGURE 12. 22kHz TONE ON 13.3V LOAD LOAD CURRENT VLNB FIGURE 14. VLNB CONNECTED TO 350mA LOAD WITH R = 148k ILIM 9 ISL9491, ISL9491A (Continued) FIGURE 11. 22kHz TONE ON 13.3V WITH 500mA FIGURE 13. AC NOISE ON 13.3V OUT OUTPUT CURRENT OUTPUT VOLTAGE FIGURE 15. VLNB SHORTED TO GND, 200mA WITH 50mA OUT ...
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... Typical Performance Curves OUTPUT CURRENT OUTPUT VOLTAGE FIGURE 16. OUTPUT CURRENT AND VOLTAGE WITH OUTPUT SHORTED TO GND, R FIGURE 18. THE ISL9491 IN THERMAL EQUILIBRIUM WITH ISL9491, ISL9491A (Continued) FIGURE 17. THE ISL9491 ENTERING THERMAL = 0 SHUTDOWN WITH R ILIM = 0 ILIM = 0 ILIM FN6531.0 October 13, 2009 ...
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... LOW), the PWM power block is disabled. When the regulator blocks are active (EN = HIGH), the output can be controlled by the VSET0 and VSET1 pins to be 13.3V, 14.3V, 18.3V or 20V (typical ISL9491) or 11V, 12V, 15V, or 16V (typical ISL9491A) for remote controlling of non- DiSEqC LNBs. A separate open-drain FAULT pin serves as an interrupt and is driven low by undervoltage, overvoltage and linear overcurrent and over-temperature faults ...
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... Current” limiting which limits current to approximately 750mA for 50ms and turns off the output for 900ms. R program the current level at which the ISL9491 enters into this protection mode. On the other hand, the ISL9491 can also be programmed in “Static Current Limit” ...
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... Package Outline Drawing L16.4x4 16 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE Rev 6, 02/08 4.00 6 PIN 1 INDEX AREA 0.15 (4X) TOP VIEW ( TYP ) ( TYPICAL RECOMMENDED LAND PATTERN 13 ISL9491, ISL9491A, ISL9491A +0.15 16X -0.10 1.00 MAX ( 12X 16X NOTES: 1. Dimensions are in millimeters. Dimensions ...