ISL6744 Intersil Corporation, ISL6744 Datasheet
ISL6744
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ISL6744 Summary of contents
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... Data Sheet Intermediate Bus PWM Controller The ISL6744 is a low cost, primary side, double-ended controller intended for applications using full and half-bridge topologies for unregulated DC/DC converters voltage- mode PWM controller designed for half-bridge and full- bridge power supplies. It provides precise control of ...
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Internal Architecture V DD UVLO + - INTERNAL BG OT SHUTDOWN 130 - 150 C GND R 2 RTD V BIAS 160 2.8 V PEAK + VALLEY 0 ...
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... Typical Application using ISL6744 - 48V Input DC Transformer, 12V @ 8A Output VIN CR3 VIN- R7 TP6 C13 TP1 R10 T2 QL C14 CR1 R5 U4 TP4 ISL6700 TP5 D2 C15 D1 R12 C6 QR1 C11 QR3 QR2 ...
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... Charged Device Model (Per EOS/ESD DS5.3, 4/14/93 .1000V Operating Conditions Temperature Range ISL6744AU . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-40°C to 105°C Supply Voltage Range (Typical 9-16 VDC CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied ...
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... Fall Time THERMAL PROTECTION Thermal Shutdown Thermal Shutdown Clear Hysteresis, Internal Protection NOTES: 3. Specifications at -40°C are guaranteed by design, not production tested. 4. Guaranteed by design, not 100% tested in production. 5 ISL6744 < 16V 51.1kΩ 470pF -40°C to 105°C (Note 4), Typical values are ...
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... RTD CURRENT (mA) FIGURE 1. OSCILLATOR CT DISCHARGE CURRENT GAIN 600 500 400 300 200 100 0 100 200 300 400 500 600 CT (pF) FIGURE 3. CAPACITANCE vs OSCILLATOR FREQUENCY (RTD = 49.9kΩ) 6 ISL6744 1-10 1-10 100 0.07 0.08 0.09 0.1 700 800 900 1000 1.07 1.06 1.05 1.04 1.03 1.02 1.01 1.00 0.99 0. RTD (kΩ) FIGURE 5. TIMING CAPACITOR VOLTAGE vs RTD www ...
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... ISL6744 Functional Description Features The ISL6744 PWM is an excellent choice for low cost bridge topologies for applications requiring accurate frequency and deadtime control. Among its many features are 1A FET current is the drivers, adjustable soft-start, overcurrent protection and ...
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... Soft-start occurs during start-up and after recovery from an overcurrent shutdown. The soft-start voltage is clamped to 4V. Gate Drive The ISL6744 is capable of sourcing and sinking 1A peak current, and may also be used in conjunction with a MOSFET driver such as the ISL6700 for level shifting. To limit the peak current through the IC, an external resistor may be placed between the totem-pole output of the IC (OUTA or OUTB pin) and the gate of the MOSFET ...
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... ISL6744 Since the converter is operating open loop at nearly 100% duty cycle, the turns ratio simply the ratio of the input voltage to the output voltage divided by 2. ...
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... DC power loss for the secondary at 20°C is 486mW. 10 ISL6744 The primary windings have an RMS current of approximately OUT configured as 2 layers, 2 turns per layer to minimize the winding stack height ...
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... FIGURE 7C. INT. LAYER 2: 2 TURNS PRIMARY WINDING FIGURE 7D. INT. LAYER 3: 2 TURNS PRIMARY WINDING FIGURE 7E. INT. LAYER 4: 1 TURN SECONDARY WINDING FIGURE 7F. BOTTOM LAYER: 1 TURN SECONDARY AND SR WINDINGS 11 ISL6744 ∅0.358 0.000 0.184 0.479 FIGURE 7G. PWB DIMENSIONS MOSFET Selection The criteria for selection of the primary side half-bridge FETs and the secondary side synchronous rectifier FETs is largely based on the current and voltage rating of the device ...
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... Ichg t • Cfet = ------------------- - ISL6744 Once the estimated transition time is determined, it must be verified directly in the application. The transformer leakage inductance was measured at 125nH and the combined capacitance was estimated at 2000pF. Calculations indicate a transition period of ~25ns. Verification of the performance yielded a value of T The remainder of the switching half-period is the charge ...
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... The peak current limit setpoint must take this behavior into consideration. A 5.11Ω current sense resistor was selected for the rectified secondary of current transformer T2 for the ISL6744Eval 1, corresponding to a peak current limit setpoint of about 11A. Performance The major performance criteria for the converter are efficiency, and to a lesser extent, load regulation ...
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... The deadtime duration of 46.9ns is clearly shown. A 2.7V zener is added between the Vdd pins of ISL6700 and ISL6744, in order to ensure that the PWM turns on only after the driver has turned on, thereby ensuring the soft-start function. Figure 17 shows the soft-start operation. ...
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... Diode, Schottky, SMA, 100V, 2.1A D1 Zener, 10V,Zetex BZX84C10ZXCT-ND D2 Zener, 2.7V, BZX84C2V7 L1 190nH Pulse, P2004T L2 1.5µH Bitech, HM73-301R5 L3 Short Jumper or Optional Discrete Leakage Inductance P1, P2, P3, P4 Keystone, 1514-2 Q5 NPN Transistor, ON MJD31C QL, QH FET, Fairchild FDS3672, 100V 15 ISL6744 FIGURE 17. OUTPUT SOFT-START DESCRIPTION www.DataSheet4U.com FN9147.8 September 22, 2005 ...
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... R10 18 Resistor, 2512, 1% R11 100 Resistor, 0603, 1% R12 10.0K Resistor, 0603 Custom Midcom 31718 T2 Custom Midcom 31719R TP1, TP2, TP4, 5002 Keystone TP5, TP6 SP1 Tektronix Scope Jack, 131-4353-00 U1 Intersil ISL6744AU, MSOP8 U4 Intersil ISL6700IB, SOIC 16 ISL6744 DESCRIPTION www.DataSheet4U.com FN9147.8 September 22, 2005 ...
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... B - 10. Datums -A - and to be determined at Datum plane . - H - 11. Controlling dimension: MILLIMETER. Converted inch dimen- sions are for reference only. 17 ISL6744 M8.118 (JEDEC MO-187AA) 8 LEAD MINI SMALL OUTLINE PLASTIC PACKAGE SYMBOL θ ...
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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 ISL6744 M8.15 (JEDEC MS-012-AA ISSUE C) 8 LEAD NARROW BODY SMALL OUTLINE PLASTIC PACKAGE ...