ISL6444 Intersil Corporation, ISL6444 Datasheet
ISL6444
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ISL6444 Summary of contents
Page 1
... Data Sheet Dual PWM Controller with DDR Memory Option for Gateway Applications The ISL6444 PWM controller provides high efficiency and regulation for two output voltages adjustable in the range from 0.9V to 5.5V that are required to power I/O, chip-sets, and memory banks in high-performance notebook computers, PDAs, and Internet appliances ...
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... Generic Application Circuits OCSET1 OCSET2 DDR ISL6444 APPLICATION CIRCUIT FOR TWO CHANNEL POWER SUPPLY +5V DDR OCSET1 V OUT3 DDR REF (+1.25V) PGOOD2/REF ISL6444 APPLICATION CIRCUIT FOR COMPLETE DDR MEMORY POWER SUPPLY 2 ISL6444 +V =+5V... +24V PWM1 PWM2 Q4 +V +5V...24V PWM1 ...
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... Soft-Start Current During Start-up Soft-Start Complete Threshold PWM CONVERTERS Load Regulation VSEN pin bias current VOUT pin input impedance 3 ISL6444 Thermal Information Thermal Resistance (Typical, Note 1) SSOP Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum Junction Temperature (Plastic Package .150 Maximum Storage Temperature Range . . . . . . . . . -65 + 0.3V Maximum Lead Temperature (Soldering 10s .300 ...
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... CCM Enforced (Hysteretic Operation Inhibited) Automatic CCM/Hysteretic Operation Enabled DDR - Low (Off) DDR - High (On) DDR REF Output Voltage DDR REF Output Current 4 ISL6444 SYMBOL TEST CONDITIONS V Fraction of the set point; ~2µs noise filter UVL V Fraction of the set point; ~2µs noise filter ...
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Block Diagram BOOT1 UGATE1 UG1 HI OVP1 PHASE1 GATE GATE LOGIC CONTROL VCC LG1 LGATE1 LO OVP1 PGND1 MODE CHANGE COMP 1 - HYST COMP 1 - EA1 VSEN1 - - Σ VREF LGATE1 LGATE1 ISEN1 CSA1 - VSEN1 OVP1 ...
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... OCSET1 (Pin 11) A resistor from this pin to ground sets the over current threshold for the first controller. 6 ISL6444 SOFT1, SOFT2 (Pin 12, 17) These pins provide soft-start function for their respective controllers. When the chip is enabled, the regulated 5µA pull-up current source charges the capacitor connected from the pin to ground ...
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... DDR memory chips is also provided. Initialization The ISL6444 initializes if at least one of the enable pins is set high. The Power-On Reset (POR) function continually monitors the bias supply voltage on the VCC pin and initiates soft-start operation after the input supply voltage exceeds 4 ...
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... The same algorithm is true for both CCM-hysteretic and hysteretic- CCM transitions. 8 ISL6444 Hysteretic Operation When the critical inductor current is detected, the converter enters hysteretic mode. The PWM comparator and the error amplifier that provided control in the CCM mode are inhibited and the hysteretic comparator is now activated ...
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... PO 2π ISL6444 where load resistance and load capacitance. For this type of modulator, a Type 2 compensation circuit is usually sufficient. Figure 5 shows a Type 2 amplifier and its response along with the responses of the current mode modulator and the converter. The Type 2 amplifier, in addition to the pole at origin, has a zero-pole pair that causes a flat gain region at frequencies in between the zero and the pole ...
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... MOSFETs. Dual-Step Conversion The ISL6444 dual channel controller can be used either in power systems with a single-stage power conversion when the battery power is converted into the desired output voltage in one step the systems where some intermediate voltages are initially established ...
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... DDR memory compliant computer. To reconfigure the ISL6444 for a complete DDR solution, the DDR pin shall be permanently set high. The simplest way to do that is to connect it to the VCC rail. This activates some functions inside the chip that are specific to the DDR memory power needs ...
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... SOURCING VTT IN-PHASE SINKING FIGURE 7. CHANNEL INTRFEARENCE Vin=7.5V...24V 12 ISL6444 Noise immunity can be improved by operating the VTT o converter with a 90 phase shift. As the time diagrams in Figure 8 show, the points of concern are always about a quarter of the period away from the noise emitting transitions ...
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... ISL6444 DC-DC Converter Application Circuits Figures 9 and 10 show application circuits of a dual channel DC/DC converter for a notebook PC. The power supply in Figure 9 provides +V2.5S and +V1.8S voltages for memory and graphic interface chipset from +5.0-24VDC battery voltage. Figure 10 shows the power supply that provides +V2.5S and +V1.8S voltages for memory and graphic interface chipset from +5 ...
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... FIGURE 10. DUAL OUTPUT APPLICATION CIRCUIT FOR TWO-STEP CONVERSION 14 ISL6444 R9 100k VIN VCC 0.01µF SOFT1 SOFT2 BOOT1 BOOT2 6 23 UGATE2 5 24 PHASE2 4 25 ISEN1 ISEN2 ISL6444 LGATE2 2 27 PGND1 PGND2 3 26 VSEN1 VSEN2 10 19 VOUT1 VOUT2 9 20 EN1 EN2 8 21 PG1 PG2/REF 15 16 OCSET2 OCSET1 ...
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... FIGURE 11. SINGLE-OUTPUT SPLIT INPUT POWER SUPPLY 15 ISL6444 C4 VIN VCC CR2 0.01µF SOFT2 BOOT2 6 23 UGATE2 5 24 PHASE2 ISEN2 ISL6444 LGATE2 2/2 IRF7313 PGND2 3 26 VSEN2 10 19 VOUT2 9 20 EN2 8 21 PG2/REF 15 16 OCSET2 DDR GND R10 0 ...
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... VIN VCC 0.01µF SOFT1 SOFT2 BOOT1 BOOT2 6 23 UGATE1 UGATE2 5 24 PHASE1 4 PHASE2 25 R1 ISEN1 ISEN2 7 22 680 ISL6444 LGATE1 LGATE2 2 27 PGND1 PGND2 3 26 VSEN1 VSEN2 10 19 VOUT1 VOUT2 9 20 EN1 EN2 8 21 PG1 PG2/REF OCSET1 OCSET2 ...
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... ISL6444 R9 100k VIN VCC SOFT1 SOFT2 BOOT1 BOOT2 6 23 UGATE1 UGATE2 5 24 PHASE1 PHASE2 4 25 ISEN1 ISEN2 ISL6444 LGATE1 LGATE2 2 27 PGND1 PGND2 3 26 VSEN1 VSEN2 10 19 VOUT1 VOUT2 9 20 EN1 EN2 8 21 PG1 PG2/REF 15 16 OCSET1 OCSET2 18 ...
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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 ISL6444 M28.15 28 LEAD SHRINK NARROW BODY SMALL OUTLINE M ...