MAX8729EEI+T Maxim Integrated Products, MAX8729EEI+T Datasheet
MAX8729EEI+T
Specifications of MAX8729EEI+T
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MAX8729EEI+T Summary of contents
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... TEMP RANGE MAX8729EEI -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. ♦ Low-Cost, Half-Bridge Inverter Topology ♦ Resonant Mode Striking Ensures Startup ♦ ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller ABSOLUTE MAXIMUM RATINGS IN GND.........................................................-0.3V to +30V BST to GND ............................................................-0.3V to +36V BST to LX..................................................................-0. GND......................................................-0.3V to +6V CC ......................................................-0. CNTL, ...
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Constant-Frequency, Half-Bridge CCFL ELECTRICAL CHARACTERISTICS (continued 12V 5.3V 0°C to +85°C, unless otherwise noted. Typical values are PARAMETER 0 < V IFB Input Bias Current -2V < V IFB ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller ELECTRICAL CHARACTERISTICS (continued 12V 5.3V 0°C to +85°C, unless otherwise noted. Typical values are PARAMETER PS1, PS2, LSYNC, HSYNC, SEL Input Low Voltage PS1, ...
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Constant-Frequency, Half-Bridge CCFL ELECTRICAL CHARACTERISTICS (V = 12V 5.3V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER IN Input-Voltage Range IN Quiescent Current V SHDN SHDN = GND IN Quiescent Current, Shutdown ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller ELECTRICAL CHARACTERISTICS (continued 12V 5.3V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER HF, HFCK, LF, LFCK Input Low Slave mode, V Voltage HF, HFCK, ...
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Constant-Frequency, Half-Bridge CCFL Inverter (Circuit of Figure 12V NORMAL OPERATION MAX8729 toc01 4ms/div A: LX, 10V/div B: IFB, 2V/div C: VFB, 2V/div 50% BRIGHTNESS DPWM OPERATION MAX8729 toc04 2ms/div A: IFB, 2V/div ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller (Circuit of Figure 12V DD, DPWM FREQUENCY vs 500 400 300 200 100 75 125 175 225 275 325 R (kΩ LINE REGULATION ...
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Constant-Frequency, Half-Bridge CCFL (Circuit of Figure 12V SYNCHRONIZATION A: LSYNC 5/div B: COMP 2V/div _______________________________________________________________________________________ Typical Operating Characteristics (continued +25°C, unless otherwise noted.) DD, A MAX8729 toc18 A B ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller PIN NAME Compensation Node of the Phase-Lock Loop. Connect a 0.1µF capacitor between PCOMP and GND 1 PCOMP to compensate the phase-lock loop. Brightness-Control Select Input. Brightness can be adjusted with an analog voltage or ...
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Constant-Frequency, Half-Bridge CCFL PIN NAME Lamp-Current Feedback Input. The IFB sense signal is internally full-wave rectified. The average value of the rectified signal is regulated to 790mV (typ) by controlling the on-time of the high-side 18 IFB MOSFET. An open-lamp ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller F1 INPUT 24V C10 0.1µF VCC C12 1µF ON/OFF DIMMING R3 100kΩ 150kΩ 1MΩ R6 1MΩ Figure 1. Typical Stand-Alone Operating Circuit 12 ______________________________________________________________________________________ VCC ...
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Constant-Frequency, Half-Bridge CCFL LINEAR IN REGULATOR GND V CC OVERVOLTAGE COMPARATOR 2.3V VFB OVER- CURRENT COMP 1.2mA 100µA IFB F.W. RECT 790mV DPWM DIMMING CONTROL SEL LOGIC CNTL OPEN-LAMP COMPARATOR 790mV OVER- CURRENT ISEC 1.25V SECONDARY OVERCURRENT COMPARATOR TFLT Figure ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller Detailed Description Figure 1 shows the Stand-Alone Typical Operating Circuit. Figure 2 shows the Functional Diagram of the MAX8729. The circuit architecture consists of a half- bridge inverter, which converts unregulated DC into a nearly ...
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Constant-Frequency, Half-Bridge CCFL PRIMARY CURRENT CLOCK SIGNAL DH PRIMARY CURRENT CLOCK SIGNAL DH Figure 3. Constant-Frequency-Operation Timing Diagram ______________________________________________________________________________________ (A) PRIMARY CURRENT CROSSES ZERO BEFORE CLOCK SIGNAL ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller continues below ground to start the negative cycle. During the negative half cycle, the controller turns off the low-side switch After which, the controller 4 turns on the high-side switch under ZVS ...
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Constant-Frequency, Half-Bridge CCFL Upon power-up, V slowly rises, increasing the duty COMP cycle of the high-side MOSFET switches and providing a measure of soft-start. In addition, the MAX8729 charges V to the overvoltage threshold (2.3V, typ) immediately FB after the ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller Lamp-Out Protection For safety, the MAX8729 monitors the lamp-current feedback (IFB) to detect faulty or open CCFL lamps and shorted IFB sense resistor. As described in the Lamp-Current Regulation section, the voltage on IFB is ...
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Constant-Frequency, Half-Bridge CCFL Table 1 Phase Shift Setting PIN SETTING PS2 PS1 MASTER GND GND 0 GND GND Don’t care. the slave IC. To ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller Table 2. Operation Summary MASTER MODE USING PIN NAME 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 ...
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Constant-Frequency, Half-Bridge CCFL Applications Information The MAX8729 requires two external n-channel power MOSFETs to form a half-bridge inverter circuit to drive the transformer primary. Since the positive half-cycle and negative half-cycle are symmetrical, the same type of MOSFET should be ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller Setting the Lamp Current The MAX8729 senses the lamp current flowing through resistor R1 (Figure 1) connected between the low-volt- age terminal of the lamp and ground. The voltage across R1 is fed to IFB ...
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Constant-Frequency, Half-Bridge CCFL 1:N AC SOURCE ( SOURCE (b) Figure 7. Simplified CCFL Inverter Circuit Figure 8 shows the frequency response ...
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Constant-Frequency, Half-Bridge CCFL Inverter Controller Parallel capacitor C3 sets the maximum operating fre- quency, which is also the parallel-resonant peak fre- quency. Choose ≤ π ...
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Constant-Frequency, Half-Bridge CCFL 3) Route high-speed switching nodes away from sen- sitive analog areas (V , COMP, HF, LF, and CC TFLT). Make all pin-strap control input connections to analog ground or V rather than power ground ...
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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. 26 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc ...