ISL6524A Intersil Corporation, ISL6524A Datasheet
ISL6524A
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ISL6524A Summary of contents
Page 1
... Data Sheet VRM8.5 PWM and Triple Linear Power System Controller The ISL6524A provides the power control and protection for four output voltages in high-performance microprocessor and computer applications. The IC integrates one PWM controller and three linear controllers, as well as the monitoring and protection functions into a 28-pin SOIC package ...
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VSEN3 1.5V or 1.26V VAUX EA3 - DRIVE3 + x0.75 x0.75 + DRIVE4 - EA4 + 1.8V or 1.26V VSEN4 - FIX INHIBIT DRIVE2 - VSEN2 + EA2 UV2 - + x0.90 + SET 1. OSCILLATOR > CLK ...
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... C OUT4 3 Q3 LINEAR CONTROLLER PWM1 CONTROLLER ISL6524A LINEAR LINEAR CONTROLLER CONTROLLER FIGURE 2. SIMPLIFIED POWER SYSTEM DIAGRAM VCC DRIVE2 FAULT/RT FIX VSEN2 VTTPG ISL6524A VAUX DRIVE3 VSEN3 DRIVE4 VSEN4 SS24 C SS24 GND FIGURE 3. TYPICAL APPLICATION Q1 V OUT1 OUT4 OCSET POWERGOOD PGOOD ...
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Absolute Maximum Ratings Supply Voltage .+15V CC ...
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Electrical Specifications Recommended Operating Conditions, Unless Otherwise Noted. Refer to Figures 1, 2 and 3 (Continued) PARAMETER PWM CONTROLLERS GATE DRIVERS UGATE Source UGATE Sink LGATE Source LGATE Sink PROTECTION VSEN1 Over-Voltage (VSEN1/DACOUT) FAULT Sourcing Current OCSET Current Source Soft-Start ...
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Functional Pin Descriptions VCC (Pin 28) Provide a 12V bias supply for the IC to this pin. This pin also provides the gate bias charge for all the MOSFETs controlled by the IC. The voltage at this pin is monitored ...
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... VCC. Description Operation The ISL6524A monitors and precisely controls 4 output voltage levels (Refer to Figures designed for microprocessor computer applications with 3.3V, 5V, and 12V 7 bias input from an ATX power supply. The IC has one PWM and three linear controllers ...
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At time T4, all output voltages are within power-good limits, situation reported by the PGOOD pin going high. ATX 12V 10V VTTPG ATX 5V SS24 PGOOD 0V 3.0V ATX 3.3V V (1.8V) OUT4 V (1.5V) OUT3 0V T0 ...
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VSEN pins for under-voltage to protect against excessive currents. Figure 8 illustrates the over-current protection with an overload on OUT1. The overload is applied at T0 and the current increases through the inductor (L the OC1 comparator trips when ...
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... There are two sets of critical components in a DC-DC 1 1.675 converter using an ISL6524A controller. The switching 0 1.700 power components are the most critical because they switch 1 1.725 large amounts of energy, and as such, they tend to generate equally large amounts of noise. The critical small signal 0 1 ...
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... F F ESR Modulator Break Frequency Equations F The compensation network consists of the error amplifier (internal to the ISL6524A) and the impedance networks Z and Z closed loop transfer function with high 0dB crossing frequency (f 0dB difference between the closed loop phase at f The equations below relate the compensation network’ ...
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... One of the parameters limiting the converter’s response to a load transient is the time required to change the inductor current. Given a sufficiently fast control loop design, the ISL6524A will provide either 0% or 100% duty cycle in OUT2 should be selected for transient load regulation. V ...
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... The maximum RMS current rating requirement for the input capacitors of a buck regulator is approximately 1/2 of the DC output load current. Worst-case RMS current draw in a circuit employing the ISL6524A amounts to the largest RMS current draw of the switching regulator. Use a mix of input bypass capacitors to control the voltage overshoot across the MOSFETs ...
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... FIGURE 13. UPPER GATE DRIVE - DIRECT V 14 Linear Controllers Transistor Selection The ISL6524A linear controllers are compatible with both NPN bipolar as well as N-channel MOSFET transistors. The main criteria for selection of pass transistors for the linear regulators is package selection for efficient removal of heat. ...
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... ISL6524A DC-DC Converter Application Circuit Figure 14 shows an application circuit of a power supply for a microprocessor computer system. The power supply provides the microprocessor core voltage (V bus voltage (V ), the AGP bus voltage (V OUT2 memory controller hub voltage (V OUT4 +5V +12V +3.3V GND GND GND Q3 HUF76107 V (VTT) OUT2 +1 ...
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... Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use ...