lx1675 Microsemi Corporation, lx1675 Datasheet
lx1675
Related parts for lx1675
lx1675 Summary of contents
Page 1
... LDO output of 5A and 15A for each PWM controller. This is useful for I/O, memory, termination, and other supplies surrounding today’s micro-processor based designs. The LX1675 accepts a wide range of supply voltage ranging from 4.5V to 24V. Each PWM regulator output voltage is programmed via a simple voltage-divider network. ...
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... Multiple Output LoadSHARE™ PWM ® ................................................ 1A (200ns ................................................. 1.5A (200ns) X CCL . , θ 55°C/W MBIENT JA x θ Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET LO2 1 31 HR2 2 30 HO2 3 ...
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... Copyright © 2004 Rev. 1.2a, 2006-02-16 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Multiple Output LoadSHARE™ PWM ® Description Microsemi Integrated Products Division LX1675 D S RODUCTION ATA HEET Page 3 ...
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... TM For the LX1675ILQ the following specifications apply over the ambient temperature -40°C < TA < 85°C and for the LX1675CLQ 0°C ≤ T 85°C except where otherwise noted and the following test conditions Load 300KHz). Parameter SWITCHING REGULATORS Input Voltage ...
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... For the LX1675ILQ the following specifications apply over the ambient temperature -40°C < TA < 85°C and for the LX1675CLQ 0°C < T < 85°C except where otherwise noted and the following test conditions Load 300KHz) ...
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... AGND SF Figure 1 – Typical Block Diagram for Phases 1, and 3 VSLR 9.6V Regualtor SSL + LDOEA - 20K V REF F 500k LDOFLT SF Figure 2 – LDO Controller Block Diagram Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET +5V VIN VCx C IN HOx LX HRx ESR LOx C OUT PGx ...
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... SET PWM CYCLE COUNTER Hiccup Vref BG SS COMP Regulator - + RAMP CLK F S FAULT UVLO R SSMSK TSD AGND Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET +5V VIN VC2 C IN HO2 L2 HR2 ESR LO2 C OUT PGx VIN + VIN +5V +5V + VCCL ...
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... TP17 TP18 R16 R21 C26 22pF 45.3K 20 TP13 R17 88.7K R15 100K R18 24.3K 1.2nF C25 1.5nF C24 Bootstrapped Microsemi Integrated Products Division LX1675 D S RODUCTION ATA HEET +VIN C2 + 470uF 16V TP36 TP38 L1 6.8uh Q1A FDS6898A C4 + 470uF TP35 16V Q1B FDS6898A TP34 ...
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... NDER OLTAGE OCKOUT At power up, the LX1675 monitors the supply voltage at the VCCL pin. The VIN supply voltage has to be sufficient to produce a voltage greater that 4.4 volts at the VCCL pin before the controller will come out of the under-voltage lock-out state. The soft-start (SS) pin is held low to prevent soft-start from beginning and the oscillator is disabled and all MOSFETs are held off ...
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... V2. The high DC gain of the error amplifier will force LPF2 to always be equal to LPF1. The following calculations determine the value of the resistor divider necessary to satisfy this example. 4.67A 1.5V @ 12A 18W 7.33A Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET SHARE ( ...
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... FB2 Generator Figure 8 – LoadSHARE Using Feedback Divider Offset V 1 × K 100 then TBD 5.814 − Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET + ESR L1 V1 1.5V 10mΩ 4.67A +46.7mV Phase 1 - Offset Voltage + 1.5V @ 12A ESR L2 V2 10mΩ ...
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... Offset Amp Vos Rin - Rf Phase 2 Error Amp PWM Input - Generator FB2 62k Rb 1M Figure 9 – LoadSHARE Using Proportional Control Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET + ESR L1 1.5V V 10mΩ 1 4.67A +46.7mV Phase 1 - Offset Voltage + 1 ...
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... Max offset Error = 6mV ⎞ +5% ESR L1 = 6.3 mΩ ⎟ ⎠ -5% ESR L2 = 5.7 mΩ Phase Phase 2 current is 2.32A greater than Phase 1. Input bias current also contributes to imbalance. Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET SHARE ( ERIES ESISTOR ETHOD ...
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... The CDE Polymer AL-EL (ESRE) filter series provides excellent ESR performance at a reasonable cost. Beware of off- brand, very low-cost filter capacitors, which have been shown to degrade in both ESR and general electrolytic characteristics over time. D × Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET ( ) × + < ...
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... PWM cycles. If the current limit condition goes away t after a count of 2 the counter will be reset. This mode will prevent a single cycle current or noise glitch from starting the hiccup mode current limit. Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET equal to 0.1µF or greater are unlikely to result ...
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... VDD is generally equal to VDDQ so that only V VDDQ are required. The LX1675 can supply both voltages by using two of the three PWM phases. Since the currents for V are quite often several amps, ( common) a switching ) which ...
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... This will allow a smooth ramp up of the LDO voltage rail. The voltage rail for the LDO pass transistor can come from any of the other PWM phases if desirable. If the VIN power supply Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET ...
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... Recommended Solder Pad Layout 7.50mm 6.10mm 5.20mm 0.25mm 3.15mm Microsemi Integrated Products Division LX1675 RODUCTION ATA HEET M I ILLIMETERS NCHES MIN MAX MIN MAX 0.80 1.00 0.031 0.039 0 0.05 0 0.002 0.20 REF 0.008 REF 0.18 ...
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... Copyright © 2004 Rev. 1.2a, 2006-02-16 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Multiple Output LoadSHARE™ PWM ® P RODUCTION Microsemi Integrated Products Division LX1675 D S ATA HEET Page 19 ...