el7641 Intersil Corporation, el7641 Datasheet
el7641
Related parts for el7641
el7641 Summary of contents
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... V and V applications. COM GAMMA The boost converter in the EL7640, EL7641, and EL7642 is a current mode PWM type integrating an 18V N-channel MOSFET. Operating at 1.2MHz, this boost can operate in either P-mode for superior transient response PI-mode for tighter output regulation. ...
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... POS1 NOT INTERNALLY CONNECTED IC = INTERNALLY CONNECTED EL7642 (32 LD QFN) TOP VIEW SRC 1 REF 2 AGND 3 PGND 4 THERMAL PAD OUT1 5 NEG1 6 POS1 7 OUT2 8 2 EL7640, EL7641, EL7642 24 COMP SRC REF AGND PGND OUT1 NEG1 POS1 ...
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... Current Limit LIM t B Soft-Start Period SS 3 EL7640, EL7641, EL7642 = 25°C) COM, DRN to AGND . . . . . . . . . . . . . . . . . . . . -0. +0.3V LX Maximum Continuous RMS Output Current 1.6A IN OUT1, OUT2, OUT3, OUT4, OUT5 Maximum Continuous Output Current . . . . . . . . . . . . . . . . . . ±75mA Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C Maximum Continuous Junction Temperature . . . . . . . . . . . . +125°C Power Dissipation ...
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... Negative LDO Input Bias Current BN FBN Load Regulation I Source Current DRVN I N DRVN Off Leakage Current LEAK t N Soft-start Period SS 4 EL7640, EL7641, EL7642 = V = 12V 20V, Over temperature from -40°C to 85°C. BOOST SUP SRC CONDITIONS I = 100µA OUT I = 5mA OUT I = -100µ ...
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... Delay Between V and V DEL2 ON t Delay From DEL3 Delay Capacitor DEL NOTE: 1. Guaranteed by design. 5 EL7640, EL7641, EL7642 = V = 12V 20V, Over temperature from -40°C to 85°C. BOOST SUP SRC CONDITIONS V = 2. 2.6V to 5.5V IN CTL = AGND or IN 1kΩ from DRN to 8V, V ...
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... DRVP 26 FBN 27 DRVN 28 DEL 29 CTL 30 DRN 31 COM 32 6 EL7640, EL7641, EL7642 EL7640 1 1 Upper reference voltage for switch output 2 2 Internal reference bypass terminal 3 3 Analog ground for boost converter and control circuitry 4 4 Power ground for boost switch 5 5 Operational amplifier 1 output ...
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... MODE) 0.12 0.1 0.08 0.06 0.04 0. 3.5 4 4.5 INPUT VOLTAGE (V) FIGURE 5. BOOST LINE REGULATION vs INPUT VOLTAGE (PI MODE) 7 EL7640, EL7641, EL7642 1000 1200 = 12V (PI MODE) FIGURE 2. BOOST EFFICIENCY AT V OUT 800 1000 1200 FIGURE 4. BOOST LOAD REGULATION vs LOAD CURRENT 5 5.5 6 FIGURE 6. BOOST LINE REGULATION vs INPUT VOLTAGE 94 92 ...
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... INPUT VOLTAGE (V) FIGURE 9. V LINE REGULATION ON 0 -0.1 -0.2 -0.3 -0.4 V =-8V -0.5 OFF I =50mA LOAD -0.6 -15 -14 -13 -12 INPUT VOLTAGE (V) FIGURE 11. V LINE REGULATION OFF 8 EL7640, EL7641, EL7642 (Continued) V =12V BOOST C =30µF OUT V =20V ON I =20mA LOAD -11 - -0.05 -0.1 -0.15 -0.2 -0. ...
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... AMBIENT TEMPERATURE (°C) FIGURE 15. PACKAGE POWER DISSIPATION vs AMBIENT TEMPERATURE Applications Information The EL7640, EL7641, EL7642 provide a highly integrated multiple output power solution for TFT-LCD applications. The system consists of one high efficiency boost converter and two low cost linear-regulator controllers ( with multiple protection functions. The block diagram OFF of the whole part is shown in Figure 17 ...
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... LCD panel design. The boost converter can operate in continuous or discontinuous inductor current mode. The EL7640, EL7641, EL7642 are designed for continuous current mode, but they can also operate in discontinuous current mode at light load. ...
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... LMT COMPENSATION I FB CURRENT AMPLIFIER I REF FBB AMPLIFIER REFERENCE GENERATOR FIGURE 18. THE BLOCK DIAGRAM OF THE BOOST CONTROLLER 11 EL7640, EL7641, EL7642 Where ∆ peak to peak inductor ripple current, and is set by: ∆ where f CLOCK SLOPE PWM LOGIC GM VOLTAGE AMPLIFIER COMP --------- × ...
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... Compensation 1.2 1360 The EL7640, EL7641, EL7642 can operate in either P mode or PI mode. Connecting COMP pin directly to V 1.2 944 P mode; For better load regulation, use PI mode with a 1.2 694 2.2nF capacitor and a 180Ω resistor in series between COMP pin and ground ...
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... Typical V voltage supported by EL7640, EL7641 and EL7642 ON ranges from +15V to +36V. A fault comparator is also included for monitoring the output voltage. The under- voltage threshold is set at 25% below the 1 ...
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... Q11 in the application diagram, then for a maximum V operating requirement of 50mA the data ON sheet indicates Hfe_min = 60. The base-emitter saturation voltage is: Vbe_max = 0.7V. For the EL7640, EL7641 and EL7642, the minimum drive current is: I_DRVP_min = 2mA The minimum base-emitter resistor, RBP, can now be calculated as: RBP_min = VBE_max/(I_DRVP_min - Ic/Hfe_min) = 0.7V/(2mA - 50mA/60) = 600Ω ...
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... BOOST L = 6.8µH and I(V ) > 74mA BOOST L = 3.3µH and I(V ) > 153mA BOOST 15 EL7640, EL7641, EL7642 Start-up Sequence Figure 23 shows a detailed start-up sequence waveform. For a successful power-up, there should be 6 peaks at V and V ON OFF When a fault is detected, the device will latch off until either EN is toggled or the input supply is recycled ...
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... REF period of typically 230ms). Fault Sequencing The EL7640, EL7641 and EL7642 have an advanced fault detection system which protects the IC from both adjacent pin shorts during operation and shorts on the output NORMAL FAULT ...
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... R can be adjusted to adjust the slew rate Amps The EL7640, EL7641 and EL7642 have 1, 3 and 5 amplifiers respectively. The op amps are typically used to drive the TFT-LCD backplane ( the gamma-correction COM divider string. They feature rail-to-rail input and output capability, they are unity gain stable, and have low power consumption (typical 600µ ...
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... V MAIN V COM FB4 V COM4 V COM SET4 V COM FB2 V COM2 V COM SET2 18 EL7640, EL7641, EL7642 9. Minimize feedback input track lengths to avoid switching noise pick-up. A demo board is available to illustrate the proper layout implementation. capacitor DELAY D21 0.1µ 6.8µH IN BOOST COMP DRVN ...
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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 19 EL7640, EL7641, EL7642 FN7415.2 February 22, 2006 ...