MAX8751ETJ+ Maxim Integrated Products, MAX8751ETJ+ Datasheet
MAX8751ETJ+
Specifications of MAX8751ETJ+
Related parts for MAX8751ETJ+
MAX8751ETJ+ Summary of contents
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... TEMP RANGE MAX8751ETJ -40°C to +85°C Pin Configuration appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ♦ All n-Type MOSFET Low-Cost, Full-Bridge, Fixed-Frequency Inverter Topology for Highest Efficiency ♦ ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller ABSOLUTE MAXIMUM RATINGS IN, LX1, LX2 to GND...............................................-0.3V to +30V BST1, BST2 to GND ...............................................-0.3V to +36V BST2 to LX2..............................................................-0. GND ..............................................................-0.3V to +6V CC GH1 to LX1 ................................................-0. ...
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Fixed-Frequency, Full-Bridge CCFL ELECTRICAL CHARACTERISTICS (continued 24V 0°C to +85°C, unless otherwise noted. Typical values are PARAMETER IFB Lamp-Out Threshold Reject 1µs glitches IFB-to-COMP Transconductance 1V < V COMP Output Impedance COMP ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller ELECTRICAL CHARACTERISTICS (continued 24V 0°C to +85°C, unless otherwise noted. Typical values are PARAMETER LF Input Frequency Range Slave mode, V LSYNC Input Frequency Range R LF ...
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Fixed-Frequency, Full-Bridge CCFL ELECTRICAL CHARACTERISTICS (V = 24V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER IN Input-Voltage Range IN Quiescent Current V SHDN IN Quiescent Current, Shutdown V SHDN V Output Voltage, Normal V ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller ELECTRICAL CHARACTERISTICS (continued 24V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER HF Input-Frequency Range Slave mode, V HSYNC Input Frequency Range Slave mode, V HFCK Input Frequency ...
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Fixed-Frequency, Full-Bridge CCFL (Circuit of Figure 12V +25°C, unless otherwise noted NORMAL OPERATION MAX8751 toc01 20µs/div A: VFB, 1V/div B: LX1, 10V/div C: LX2, 10V/div D: IFB, 2V/div 50% ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller (Circuit of Figure 12V +25°C, unless otherwise noted DPWM SOFT-START MAX8751 toc07 100µs/div A: COMP, 1V/div B: IFB, 1V/div C: VFB, 1V/div SWITCHING FREQUENCY vs ...
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Fixed-Frequency, Full-Bridge CCFL (Circuit of Figure 12V +25°C, unless otherwise noted vs. TEMPERATURE CC 5. 12V IN NOT SWITCHING 5.38 5.36 5.34 5.32 5. TEMPERATURE ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller PIN NAME Transformer Secondary Voltage-Feedback Input. VFB pin sets secondary overvoltage limit by using a capacitive voltage-divider between the high voltage of the CCFL lamp and GND. When the peak 1 VFB voltage on VFB ...
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Fixed-Frequency, Full-Bridge CCFL PIN NAME 18 GH2 Gate-Driver Output for High-Side MOSFET NH2 Gate-Driver Return for GH2. LX2 is the input to the primary current-limit and zero-crossing comparators. The controller senses the voltage across the low-side MOSFET NL2 (LX2 - ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller 24V GND IN C10 1.0µF GND C12 SEL 1.0µF ON/OFF SHDN CNTL BRIGHTNESS PCOMP C7 0.1uF HF R3 100kΩ 150kΩ1% HFCK R5 HSYNC 1MΩ LSYNC ...
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Fixed-Frequency, Full-Bridge CCFL LINEAR IN REGULATOR GND V CC OVERVOLTAGE COMPARATOR 2.25V VFB OVER- CURRENT COMP 1200µA 100µA IFB F.W. RECT 790mV DPWM DIMMING CONTROL SEL LOGIC CNTL OPEN-LAMP COMPARATOR 780mV OVER- CURRENT ISEC 1.22V SECONDARY OVERCURRENT COMPARATOR TFLT Figure ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller Detailed Description Figure 1 shows the Stand-Alone Typical Operating Circuit and Figure 2 shows the Functional Diagram of the MAX8751. The circuit in Figure 1 consists of a full- bridge inverter, which converts unregulated DC ...
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Fixed-Frequency, Full-Bridge CCFL PRIMARY CURRENT INTERNAL OSCILLATOR Figure 3. Fixed-Frequency Timing Diagram Figure 4. Resonant Operation Timing Diagram ______________________________________________________________________________________ DH1 DH2 DL1 DL2 PRIMARY CURRENT DH1 DH2 DL1 DL2 Inverter Controller 15 ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller mode, at the beginning of the positive half cycle, NH1 and NL2 turn on and the primary current starts ramping up. The controller turns off NH1 as the primary current reaches its peak value. The ...
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Fixed-Frequency, Full-Bridge CCFL the end of the DPWM on-cycle, the dimming control logic turns on a 100µA internal current source, thus dis- charging the COMP capacitor linearly, gradually decreasing t and bringing lamp current to zero, thus ON providing soft-start. ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller Secondary Current Limit (ISEC) The secondary current limit provides fail-safe protection in case of short circuit or leakage from the high-voltage terminal to ground. ISEC monitors the voltage across a sense resistor placed between the ...
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Fixed-Frequency, Full-Bridge CCFL Table 1. Phase-Shift Setting PIN SETTING PS2 PS1 MASTER X X GND GND GND GND Don’t care. Linear Regulator Output (V The internal linear regulator steps down ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller Table 2. Operation Summary MASTER MODE USING PIN INTERNAL OSCILLATORS An analog voltage on CNTL CNTL sets the brightness. SEL Connect SEL to GND. Connect a resistor to GND to HF set the switching frequency. ...
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Fixed-Frequency, Full-Bridge CCFL 380mV = I LIM_MIN R DS(ON)_MAX 420mV = I LIM_MAX R DS(ON)_MIN MOSFETs must be able to dissipate the conduction losses plus the switching losses at both Calculate both terms. Ideally, the losses at ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller Setting the Secondary Current Limit The MAX8751 limits the secondary current even if the IFB sense resistor is shorted or transformer secondary current finds its way to ground without passing through R1. ISEC monitors the ...
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Fixed-Frequency, Full-Bridge CCFL C S 1:N AC SOURCE (a) 2 Cs' = Cs'/ SOURCE (b) Figure 7. Simplified CCFL Inverte r Circuit 2 N ≤ 4π MIN where f is the minimum ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller 30µA, the rise time is about three times longer than the fall time. Setting the Fault Delay Time The TFLT capacitor determines the delay time for both the open-lamp fault and secondary short-circuit fault. The ...
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Fixed-Frequency, Full-Bridge CCFL Pin Configuration TOP VIEW GL1 25 PGND1 26 27 GND 28 PCOMP MAX8751ETJ 29 COMP IFB 30 31 PS2 32 ISEC TQFN 5mm x 5mm ...
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Fixed-Frequency, Full-Bridge CCFL Inverter Controller (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 26 ______________________________________________________________________________________ Package Information ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 27 © 2005 Maxim Integrated Products ...