el7520a Intersil Corporation, el7520a Datasheet
el7520a
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el7520a Summary of contents
Page 1
... Therefore, they are ideal to use in any size of TFT-LCD panels. The EL7520 and EL7520A are available 4x4 QFN package with maximum height of 0.9mm and is specified for operation of the -40°C to +85°C temperature range. ...
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... Ambient Operating Temperature . . . . . . . . . . . . . . . .-40°C to +85°C Maximum Continuous Junction Temperature . . . . . . . . . . . . . 125° 11V 40mA 15V, V BOOST LOAD ON CONDITION Enabled, LX not switching Disabled, EL7520 Disabled, EL7520A T = 25° 25° falling FBB Test with 24mΩ R DS(ON 400mA LOAD PI mode ...
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... OT Over-temperature Threshold I PG Pull-down Current PG LOGIC V Logic High Threshold HI V Logic Low Threshold LO I Logic Low bias Current LOW I Logic High bias Current HIGH 3 EL7520, EL7520A = 11V 40mA 15V, V BOOST LOAD ON CONDITION I 0mA to 20mA 1.1V 25V FBP DRVP V = 1.5V 35V FBL ...
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... LINE REGULATION BOOST 200 400 600 I (mA) OUT FIGURE 5. V LOAD REGULATION (P MODE) BOOST 4 EL7520, EL7520A 1000 1500 (PI MODE) OUT 0 P MODE -0.005 -0.01 -0.015 -0.02 -0.025 PI MODE -0. 800 1000 1200 100 ...
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... OUT FIGURE 7. V LOAD REGULATION OFF V CDLY EN V LOGIC V REF TIME (20ms/DIV) FIGURE 9. EL7520 START-UP SEQUENCE V BOOST V LOGIC V OFF V ON TIME (10ms/DIV) FIGURE 11. EL7520 START-UP SEQUENCE 5 EL7520, EL7520A (Continued) -0.2 -0.4 -0.6 -0.8 -1.2 80 100 V CDLY V BOOST V LOGIC C =0.1µF DLY V REF FIGURE 10. EL7520 START-UP SEQUENCE V BOOST-DELAY V ...
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... EL7520, EL7520A (Continued BOOST V LOGIC C =0.1µF DLY V BOOST-DELAY C =0.1µF DLY 0.5µs/DIV FIGURE 17. LX WAVEFORM-DISCONTINUOUS MODE CDLY V REF C TIME (20ms/DIV) FIGURE 14. EL7520A START-UP SEQUENCE V LOGIC V OFF V ON TIME (20ms/DIV) FIGURE 16. EL7520A START-UP SEQUENCE =0.1µF DLY C =0.1µF DLY FN7318.0 July 12, 2005 ...
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... FIGURE 20. V TRANSIENT RESPONSE BOOST CH1=V , 100mV/DIV ON CH4=LOAD CURRENT, 50mA/DIV 50µs/DIV FIGURE 22. V TRANSIENT RESPONSE ON 7 EL7520, EL7520A (Continued) FIGURE 19. V FIGURE 21. V FIGURE 23. V 20mV/DIV OUTPUT VOLTAGE RIPPLE BOOST CH1=V , 20mV/DIV LOGIC CH4=LOAD CURRENT, 100mA/DIV 50µs/DIV TRANSIENT RESPONSE ...
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... PG Output gate drive of the external fault protection P channel FET; when chip is disabled or when a fault has been detected, this pin is high 8 EL7520, EL7520A FUNCTION DESCRIPTION integrator output, connect 2.2nF to analog GND for PI mode or connect channel FET; when fault is detected, BOOST ...
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... C 10µ Applications Information The EL7520 and EL7520A provide a multiple output power supply solution for TFT-LCD applications. The system consists of a high efficiency boost controller and three low cost linear-regulator controllers ( The block diagram of the whole part is shown in Figure 24. ...
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... LCD panel design. The boost converter can operate in continuous or discontinuous inductor current mode. The EL7520 and EL7520A are designed for continuous current mode, but they can also operate in discontinuous current mode at light load. In continuous current mode, current flows continuously in the inductor during the entire switching cycle in steady state operation ...
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... REF BE SAD V ISAD ---------------- - I = SAD R1 ≈ 0.7V Where V BE The external resistor R should be chosen in the order of 1 100K to generate µA of current. 11 EL7520, EL7520A OSCILLATOR SLOPE OSC COMPENSATION PWM LOGIC Σ CONTROLLER VOLTAGE AMPLIFIER CURRENT AMPLIFIER SHUTDOWN & STARTUP CONTROL CURRENT LIMIT COMPARATOR when the ...
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... The voltage rating of the output capacitor should be larger than 10µF. be greater than the maximum output voltage Compensation The EL7520 and EL7520A can operate in either P mode or PI mode. Connecting C P mode. For better load regulation, use PI mode with a 2.2nF capacitor between C Linear-Regulator Controllers (V V ...
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... GML 1: N1 FUNCTIONAL BLOCK DIAGRAM LOGIC power supply is used to power the positive supply ON voltage supported by EL7520, EL7520A range from power supply is used to power the negative OFF voltage supported by EL7520, EL7520A range OFF power supply is used to power the logic circuitry LOGIC ...
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... PMOS FET can be used to delay the output until the boost is enabled internally. The delayed output appears at A For EL7520 the third ramp. The soft-start ramp depends on the value of the C is ~2ms. EL7520A is the same as EL7520 except that V and V V OFF peak, DELB gate goes low to turn on the external PMOS Q4 ...
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... EL7520, EL7520A V CDLY EN V REF V BOOST LOGIC V OFF t DEL1 DELAYED V BOOST V ON START-UP SEQUENCE TIMED BY C FIGURE 30. EL7520 START-UP SEQUENCE DEL2 DLY FN7318.0 July 12, 2005 ...
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... EL7520, EL7520A V CDLY REF V BOOST LOGIC V OFF t DEL1 DELAYED V BOOST V ON START-UP SEQUENCE TIMED BY C FIGURE 31. EL7520A START-UP SEQUENCE DEL2 t DEL3 DLY FN7318.0 July 12, 2005 ...
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... The feedback network should sense the output voltage directly from the point of load, and be as far away from LX node as possible. 5. The power ground (PGND) and signal ground (SGND) pins should be connected at only one point. A demo board is available to illustrate the proper layout implementation. 17 EL7520, EL7520A FN7318.0 July 12, 2005 ...
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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 18 EL7520, EL7520A FN7318.0 July 12, 2005 ...