el7641a Intersil Corporation, el7641a Datasheet
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el7641a
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el7641a Summary of contents
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... Data Sheet PRELIMINARY TFT-LCD DC/DC with Integrated Amplifiers The EL7640A, EL7641A, and EL7642A integrate a high performance boost regulator with 2 LDO controllers for V and -slice circuit with adjustable delay and OFF ON either one (EL7640A), three (EL7641A), or five amplifiers (EL7642A) for V and V applications ...
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... POS1 NOT INTERNALLY CONNECTED IC = INTERNALLY CONNECTED EL7642A (32 LD QFN) TOP VIEW SRC 1 REF 2 AGND 3 PGND 4 THERMAL PAD OUT1 5 NEG1 6 POS1 7 OUT2 8 2 EL7640A, EL7641A, EL7642A 24 COMP SRC REF AGND PGND OUT1 NEG1 POS1 ...
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... Current Limit LIM t B Soft-Start Period SS 3 EL7640A, EL7641A, EL7642A = 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 EL7640A, EL7641A, EL7642A = 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 EL7640A, EL7641A, EL7642A = 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 EL7640A, EL7641A, EL7642A EL7640A 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 EL7640A, EL7641A, EL7642A 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 EL7640A, EL7641A, EL7642A (Continued) V =12V BOOST C =30µF OUT V =20V ON I =20mA LOAD -11 - =20V ON -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 EL7640A, EL7641A, EL7642A 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 (V and V ) with multiple protection functions ...
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... LCD panel design. The boost converter can operate in continuous or discontinuous inductor current mode. The EL7640A, EL7641A, EL7642A 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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... LMT COMPENSATION I FB CURRENT AMPLIFIER I REF FBB AMPLIFIER REFERENCE GENERATOR FIGURE 18. THE BLOCK DIAGRAM OF THE BOOST CONTROLLER 11 EL7640A, EL7641A, EL7642A 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 EL7640A, EL7641A, EL7642A can operate in either P mode or PI mode. Connecting COMP pin directly to V 1.2 944 enable P mode; For better load regulation, use PI mode with 1.2 694 a 2.2nF capacitor and a 180Ω resistor in series between COMP pin and ground ...
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... ON of 10). Typical EL7641A and EL7642A ranges from -5V to -25V. A fault R P2 comparator is also included for monitoring the output 20kΩ voltage. The under-voltage threshold is set at 200mV above the 0.2V reference level. ...
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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 EL7640A, EL7641A and EL7642A, 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 EL7640A, EL7641A, EL7642A 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 out period of typically 230ms). Fault Sequencing The EL7640A, EL7641A and EL7642A 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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... EL7640A, EL7641A, EL7642A Driving Capacitive Loads EL7640A, EL7641A and EL7642A can drive a wide range of capacitive loads. As load capacitance increases, however, the –3dB bandwidth of the device will decrease and the peaking will increase. The amplifiers drive 10pF loads in parallel with 10kΩ with just 1.5dB of peaking, and 100pF with 6.4dB of peaking. If less peaking is desired in these applications, a small series resistor (usually between 5Ω ...
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... V MAIN V COM FB4 V COM4 V COM SET4 V COM FB2 V COM2 V COM SET2 18 EL7640A, EL7641A, EL7642A 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 EL7640A, EL7641A, EL7642A FN6270.0 May 15, 2006 ...