ISL6553 Intersil Corporation, ISL6553 Datasheet
ISL6553
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ISL6553 Summary of contents
Page 1
... TM Data Sheet Microprocessor CORE Voltage Regulator Multi-Phase Buck PWM Controller The ISL6553 multi-phase PWM control IC together with its companion gate drivers, the HIP6601, HIP6602 or HIP6603 and Intersil MOSFETs provides a precision voltage regulation system for advanced microprocessors. Multi- phase power conversion is a marked departure from earlier single phase converter confi ...
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... Block Diagram VSEN X 0.9 X1.15 AND FAULT COMP VID3 VID2 VID1 D/A VID0 VID25mV FB Simplified Power System Diagram VSEN PWM 1 ISL6553 PWM 2 VID 2 ISL6553 PGOOD VCC POWER-ON RESET (POR LATCH CLOCK AND S SAWTOOTH GENERATOR + OVP - + SOFT- START - LOGIC + - + E/A - CURRENT CORRECTION I_TOT + + ...
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... VID3 (Pin 1), VID2 (Pin 2), VID1 (Pin 3), VID0 (Pin 4) and VID25mV (Pin 5) Voltage Identification inputs from microprocessor. These pins respond to TTL and 3.3V logic signals. The ISL6553 decodes VID bits to establish the output voltage. See Table 1. COMP (Pin 6) Output of the internal error amplifier. Connect this pin to the external feedback and compensation network ...
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... Typical Application - Two Phase Converter Using an HIP6602 Gate Driver FB COMP VCC VSEN ISEN1 PGOOD PWM1 VID3 MAIN VID2 CONTROL ISL6553 VID1 VID0 PWM2 VID25mV ISEN2 FS/DIS GND 4 ISL6553 +5V BOOT1 +12V UGATE1 VCC PHASE1 LGATE1 PWM1 DUAL PVCC DRIVER HIP6602 BOOT2 PWM2 UGATE2 PHASE2 LGATE2 GND V = +12V ...
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... POWER GOOD MONITOR Under-Voltage Threshold Under-Voltage Threshold PGOOD Low Output Voltage PROTECTION Over-Voltage Threshold Percent Over-Voltage Hysteresis 5 ISL6553 Thermal Information Thermal Resistance (Typical, Note 1) + 0.3V SOIC Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VCC Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . .150 Maximum Storage Temperature Range . . . . . . . . . . -65 Maximum Lead Temperature (Soldering 10s .300 ...
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... CORRECTION FIGURE 1. SIMPLIFIED BLOCK DIAGRAM OF THE ISL6553 VOLTAGE AND CURRENT CONTROL LOOPS FOR A TWO POWER CHANNEL REGULATOR Operation Figure 1 shows a simplified diagram of the voltage regulation and current control loops. Both voltage and current feedback are used to precisely regulate voltage and tightly control ...
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... DT of 10.24ms. Figure 3 shows the start-up sequence as initiated by a fast rising 5V supply, VCC, applied to the ISL6553. Note the short rise to the three state level in PWM 1 output during first 32 PWM cycles. Figure 4 shows the waveforms when the regulator is operating at 200kHz ...
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... PGOOD voltage. Note that Figure 5 shows the 12V gate driver voltage available before the 5V supply to the ISL6553 has reached its threshold level. If conditions were reversed and the 5V supply was to rise first, the start-up sequence would be different ...
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... PWM outputs into a three state mode. This condition results in the gate driver removing drive to the output stages. The ISL6553 goes into a wait delay timing cycle that is equal to the Soft-Start ramp time. PGOOD also goes “low” during this time due to VSEN going below its threshold voltage ...
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... FIGURE 7. SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM SHOWING CURRENT AND VOLTAGE SAMPLING Current Sensing and Balancing Overview The ISL6553 samples the on-state voltage drop across each synchronous rectifier FET, Q2 indication of the inductor current in that phase, see Figure 7. Neglecting AC effects (to be discussed later), the voltage drop across Q2 is ...
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... FIGURE 9. TWO CHANNEL multi-phase SYSTEM WITH The inductor, or load current, flows alternately from V through Q1 and from ground through Q2. The ISL6553 / n), LT samples the on-state voltage drop across each Q2 transistor to indicate the inductor current in that phase. The voltage drop is sampled 1 switching period, 1/F turned OFF and Q2 is turned on ...
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... As discussed previously, the voltage drop across each Q2 transistor at the point in time when current is sampled is r (Q2 The voltage at Q2’s drain, the DSON SAMPLE PHASE node, is applied through the R ISL6553 ISEN pin. This pin is held at virtual ground, so the current into ISEN is (Q2 SENSE SAMPLE ...
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... Small values of output inductance can cause excessive power dissipation. The ISL6553 is designed for stable operation for ripple currents up to twice the load current. However, for this condition, the RMS current is 115% above the value shown in the following MOSFET Selection and Considerations section ...
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... MOSFET to suppress the voltage induced in the parasitic circuit impedances. 14 ISL6553 For bulk capacitance, several electrolytic capacitors (Panasonic HFQ series or Nichicon PL series or Sanyo MV-GX or equivalent) may be needed. For surface mount designs, solid tantalum capacitors can be used, but caution must be exercised with regard to the capacitor surge current rating ...
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... For information regarding Intersil Corporation and its products, see web site www.intersil.com Sales Office Headquarters NORTH AMERICA Intersil Corporation P. O. Box 883, Mail Stop 53-204 Melbourne, FL 32902 TEL: (321) 724-7000 FAX: (321) 724-7240 15 ISL6553 M16.15 16 LEAD NARROW BODY SMALL OUTLINE PLASTIC PACKAGE SYMBOL A ...