ISL97642 Intersil Corporation, ISL97642 Datasheet
ISL97642
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ISL97642 Summary of contents
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... V ON with adjustable delay and three amplifiers for V V applications. GAMMA The boost converter in the ISL97642 is a current mode PWM type integrating an 18V N-Channel MOSFET. Using external low-cost transistors, the LDO controllers provide tight regulation for start-up sequence control and fault protection. ...
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... Pinouts www.DataSheet4U.com 2 ISL97642 ISL97642 (32 LD TQFN) TOP VIEW SRC 1 REF 2 AGND 3 PGND 4 THERMAL PAD OUT1 5 NEG1 6 POS1 7 OUT2 NOT INTERNALLY CONNECTED 24 COMP OUT3 June 18, 2007 FN6436.0 ...
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... LX Leakage Current LEAK Current Limit LIM t B Soft-Start Period SS 3 ISL97642 Thermal Information (T = +25°C) A Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C +0.3V Maximum Continuous Junction Temperature . . . . . . . . . . . . +125°C IN Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Curves Operating Ambient Temperature . . . . . . . . . . . . . . . .-40°C to +85°C Pb-free reflow profile . . . . . . . . . . . . . . . . . . . . . . . . . .see link below -20V ...
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... N DRVN Off Leakage Current LEAK t N Soft-start Period SS V -SLICE CIRCUIT ON V CTL Input Low Voltage LO V CTL Input High Voltage HI 4 ISL97642 = 3V 12V 20V, Over-temperature from -40°C to +85°C. IN BOOST SUP SRC CONDITIONS I = 100µA OUT I = 5mA OUT I = -100µA ...
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... Delay Between V DEL2 t Delay From V DEL3 C Delay Capacitor DEL NOTE: 1. Limits should be considered typical and are not production tested. www.DataSheet4U.com 5 ISL97642 = 3V 12V 20V, Over-temperature from -40°C to +85°C. IN BOOST SUP SRC CONDITIONS CTL = AGND or IN 1kΩ from DRN to 8V step, no load on OUT, measured from ...
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... CTL 30 DRN 31 COM 32 6 ISL97642 PIN FUNCTION Upper reference voltage for switch output Internal reference bypass terminal Analog ground for boost converter and control circuitry Power ground for boost switch Operational amplifier 1 output Operational amplifier 1 inverting input Operational amplifier 1 non-inverting input ...
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... IN -0.5 -0.6 0 200 400 600 LOAD CURRENT (mA) FIGURE 3. BOOST LOAD REGULATION vs LOAD CURRENT (PI MODE) www.DataSheet4U.com 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 3.0 3.5 4.0 4.5 INPUT VOLTAGE (V) FIGURE 5. BOOST LINE REGULATION vs INPUT VOLTAGE (P MODE) 7 ISL97642 800 1000 1200 = 12V (PI MODE) OUT 800 1000 1200 5.0 5.5 6 ...
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... V LOAD CURRENT (mA) ON FIGURE 7. V LOAD REGULATION ON 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 -0.7 -0.8 -0 LOAD CURRENT (mA) FIGURE 9. V LOAD REGULATION OFF www.DataSheet4U.com TIME (20ms/DIV) FIGURE 11. START-UP SEQUENCE 8 ISL97642 (Continued 20V -8V OFF CDEL V BOOST V OFF -0.02 -0.04 -0.06 -0. 20V ON -0. 20mA LOAD -0 ...
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... FIGURE 13. OP AMP RAIL-TO-RAIL INPUT/OUTPUT FIGURE 15. PACKAGE POWER DISSIPATION vs AMBIENT TEMPERATURE Applications Information www.DataSheet4U.com The ISL97642 provides 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 multiple protection functions ...
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... LCD panel design. The boost converter can operate in continuous or discontinuous inductor current mode. The ISL97642 is designed for continuous current mode, but it can also operate in discontinuous current mode at light load. In ...
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... OMAX LMT REF FBB www.DataSheet4U.com 11 ISL97642 Where Δ peak to peak inductor ripple current, and is set by Equation 4: (EQ. 3) where f CLOCK SLOPE COMPENSATION CURRENT AMPLIFIER GM AMPLIFIER REFERENCE GENERATOR COMP FIGURE 17. THE BLOCK DIAGRAM OF THE BOOST CONTROLLER ...
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... The ISL97642 incorporates a transconductance amplifier in 1.2 666 its feedback path to allow the user some adjustment on the 1.2 530 transient response and better regulation. The ISL97642 uses current mode control architecture, which has a fast 1.2 1350 current sense loop and a slow voltage feedback loop. The 1.2 ...
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... Typical V voltage supported by ISL97642 ranges from +15V to ON +36V. A fault comparator is also included for monitoring the output voltage. The undervoltage threshold is set at 25% below the 1 ...
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... 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 ISL97642, the minimum drive current is: I_DRVP_min = 2mA The minimum base-emitter resistor, R calculated as: ⁄ RBP_min VBE_max (I_DRVP_min - Ic/Hfe_min = ...
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... BOOST L = 3.3µH and I(V ) > 153mA BOOST www.DataSheet4U.com 15 ISL97642 Start-up Sequence Figure 22 shows a detailed start-up sequence waveform. For regulation – depending a successful power-up, there should be 6 peaks at V 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 Fault Sequencing The ISL97642 has an advanced fault detection system, which protects the IC from both adjacent pin shorts during operation and shorts on the output supplies. A high quality should layout/design of the PCB (in respect of grounding quality and DEL (see Figure 22) ...
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... The ISL97642 has a -3dB bandwidth of 12MHz while maintaining a 10V/μs slew rate. Short Circuit Current Limit The ISL97642 will limit the short circuit current to ±180mA if the output is directly shorted to the positive or the negative supply output is shorted for a long time, the junction temperature will trigger the Over-Temperature Protection limit and, hence, the part will shut down ...
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... R21 0.1µF CONTROL INPUT 100nF www.DataSheet4U.com V MAIN V COM FB3 V COM3 V COM SET3 V COM FB2 V COM2 V COM SET2 18 ISL97642 D21 0.1µ 6.8µH 10Ω IN 470nF BOOST 180Ω COMP 2.2nF DRVN NEG POS REG REG FBN REF REF CTL ...
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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 ISL97642 L32.5x5A 0.15 C ...