ISL6545 INTERSIL [Intersil Corporation], ISL6545 Datasheet
ISL6545
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ISL6545 Summary of contents
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... N-Channel MOSFETs in a synchronous buck topology. Since it can work with either 5V or 12V supplies, this one IC can be used in a wide variety of applications within a system. The ISL6545 integrates the control, gate drivers, output adjustment, monitoring and protection functions into a single 8 Ld SOIC DFN package. ...
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... RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 2 ISL6545, ISL6545A FIXED FREQUENCY OSCILLATOR TEMP. RANGE (kHz) (° ...
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... Block Diagram SAMPLE AND HOLD 21.5µA TO LGATE/OCSET FB 5V int. 20μA COMP/SD Typical Application C DCPL Type II R OFFSET compensation shown 3 ISL6545, ISL6545A POR AND + SOFT-START - OC COMPARATOR 5V int. ERROR PWM AMP COMPARATOR 0. 0.4V DIS + - OSCILLATOR FIXED 300 (or 600)kHz 12V VCC ...
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... CC Ambient Temperature Range ISL6545C, ISL6545AC . . . . . . . . . . . . . . . . . . . . . . . 0°C to +70°C ISL6545I, ISL6545AI . . . . . . . . . . . . . . . . . . . . . . .-40°C to +85°C Junction Temperature Range .-40°C to +125°C CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and result in failures not covered by warranty ...
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... Disable Threshold (COMP/SD pin) Functional Pin Description (SOIC, DFN) VCC (SOIC Pin 5, DFN Pin 6) This pin provides the bias supply for the ISL6545, as well as the lower MOSFET’s gate, and the BOOT voltage for the upper MOSFET’s gate. An internal 5V regulator will supply bias if V rises above 6 ...
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... Figure 3 shows the normal curve in blue; initialization begins at t0, and the output ramps between t1 and t2. If the output is . This OCSET pre-biased to a voltage less than the expected value, as shown by the magenta curve, the ISL6545 will detect that condition. Neither MOSFET will turn on until the soft-start is above V CC LGATE ...
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... If the shorted condition is not removed, this cycle will continue indefinitely. Following POR (and 6.8ms delay), the ISL6545 initiates the Overcurrent Protection sample and hold operation. The LGATE driver is disabled to allow an internal 21.5µA current ...
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... Output Voltage Selection The output voltage can be programmed to any level between the 0.6V internal reference the V ISL6545 can run at near 100% duty cycle at zero load, but the r DS(ON) something less as the load current increases. In addition, the OCP (if enabled) will also limit the maximum effective duty cycle ...
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... CC The switching frequency is either a fixed 300kHz or 600kHz, depending on the part number chosen (ISL6545 is 300kHz; ISL6545A is 600kHz; the generic name “ISL6545” may apply to either in the rest of this document, except when choosing the frequency). However, all of the other timing mentioned (POR delay, OCP sample, soft-start, etc.) is independent of the clock frequency (unless otherwise noted) ...
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... The components shown should 10 ISL6545, ISL6545A be located as close together as possible. Please note that the capacitors C capacitors. For best results, locate the ISL6545 within 1 inch of the MOSFETs, Q gate and source connections from the ISL6545 must be sized to handle peak current. CC ...
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... C E ⋅ ⋅ 2π The compensation network consists of the error amplifier (internal to the ISL6545) and the external R1-R3, C1-C3 components. The goal of the compensation network is to provide a closed loop transfer function with high 0dB crossing frequency (F ; typically 0 margin (better than 45°). Phase margin is the difference ...
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... Given a sufficiently fast control loop design, the ISL6545 will provide either 0% or 100% duty cycle in response to a load transient. The response time is the time required to slew the inductor current from an initial current value to the transient current level ...
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... N-MOSFETs. Look for rDS(ON) ratings at 4.5V. Caution should be exercised with devices exhibiting very low VGS(ON) characteristics. The shoot-through protection present aboard the ISL6545 may be circumvented by these MOSFETs if they have large parasitic impedences and/or , gate supply capacitances that would inhibit the gate of the MOSFET from being discharged below its threshold level before the complementary MOSFET is turned on ...
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... The external diode drop has to be lower than the internal one; the resulting higher V of the upper FET will lower its r G-S DS(ON) gain in efficiency should be balanced against the extra cost and area of the external diode. 14 ISL6545, ISL6545A ≈ G ≈ ...
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... INDEX AREA (DATUM N (Nd-1)Xe REF. BOTTOM VIEW C L (A1 SECTION "C-C" FOR ODD TERMINAL/SIDE 15 ISL6545, ISL6545A L10.3x3C 0. LEAD DUAL FLAT NO-LEAD PLASTIC PACKAGE 2X 0. SYMBOL 0. 0. NOTES: 1. Dimensioning and tolerancing conform to ASME Y14.5-1994. ...
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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 16 ISL6545, ISL6545A M8.15 (JEDEC MS-012-AA ISSUE C) 8 LEAD NARROW BODY SMALL OUTLINE PLASTIC PACKAGE ...