DS3991Z+T&R/HB Maxim Integrated Products, DS3991Z+T&R/HB Datasheet
DS3991Z+T&R/HB
Specifications of DS3991Z+T&R/HB
Related parts for DS3991Z+T&R/HB
DS3991Z+T&R/HB Summary of contents
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... Half-Bridge + Denotes a lead-free package. T&R = Tape and reel. Typical Operating Circuits appear at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Low-Cost CCFL Controller ♦ CCFL Controller for Backlighting LCD Panels ♦ ...
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Low-Cost CCFL Controller ABSOLUTE MAXIMUM RATINGS Voltage Range on VCC Relative to Ground ..........-0.5V to +6.0V Voltage Range on Any Lead Other than VCC .............................................. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. ...
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ELECTRICAL CHARACTERISTICS (continued +4.5V to 5.5V -40°C to +85°C PARAMETER SYMBOL Lamp Regulation Threshold OVD Threshold V Lamp Frequency LF Lamp Frequency Tolerance LF Burst-Dimming PWM Frequency PF Burst-Dimming PWM Frequency PF Tolerance BRIGHT ...
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Low-Cost CCFL Controller (V = 5.0V +25°C, multilamp configuration, unless otherwise noted PUSH-PULL TYPICAL OPERATION 12.5V INV 20μs 5.0V GA 20μs 5.0V GB 20μs 2.0V LCM 20μs 2.0V OVD PUSH-PULL SOFT-START AT V ...
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T = +25°C, single-lamp configuration, unless otherwise noted HALF-BRIDGE NORMAL OPERATION, 20μs 20μs 5.0V GA 20μs 5.0V GB 20μs 2.0V LCM 20μs 2.0V OVD HALF-BRIDGE LAMP STRIKE, EXPANDED VIEW 0.5ms 5.0V GA 0.5ms 5.0V GB ...
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Low-Cost CCFL Controller PIN NAME I/O BRIGHT Slope Select. This digital input determines the slope of the BRIGHT input when an analog DC voltage is used to control lamp brightness (PWM_EN = 0). 1 SLOPE I SLOPE = 0: positive ...
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TO 80kHz LOSC OSCILLATOR (±5%) EXTERNAL RESISTOR LAMP FREQUENCY SET PWM_EN ANALOG LAMP BRIGHTNESS CONTROL (PWM_EN = 0) BRIGHT NEGATIVE SLOPE SLOPE PWM LAMP POSC BRIGHTNESS CONTROL OSCILLATOR (±5%) (PWM_EN = 1) EXTERNAL RESISTOR BURST-DIMMING FREQUENCY SET _______________________________________________________________________________________ Low-Cost ...
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Low-Cost CCFL Controller CHANNEL ENABLE CHANNEL FAULT DIGITAL BURST-DIMMING CCFL PWM SIGNAL CONTROLLER LAMP FREQUENCY (40kHz TO 80kHz) Detailed Description The DS3991 is available for both push-pull and half- bridge drive topologies. In both drive topologies, the DS3991 drives two ...
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BURST-DIMMING PWM SIGNAL (EITHER CREATED INSIDE THE DS3991 OR SOURCED AT THE POSC/PWM PIN) LAMP CURRENT SOFT-START Figure 1. Digital PWM Dimming and Soft-Start If the PWM_EN pin is tied high, the digital control method is enabled and an external ...
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Low-Cost CCFL Controller V INV TRIP R 1 Figure 2. Setting the SVML and SVMH Threshold Voltages LAMP OVERCURRENT (INSTANTANEOUS) Figure 3. Fault-Handling Flowchart causing spurious operation when V point. This monitor cannot be disabled by any ...
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If during the strike ramp, the maximum allowable voltage is reached, the controller stops increasing the MOSFET gate duty cycle to keep from overstressing the system. The DS3991 ...
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Low-Cost CCFL Controller DEVICE SUPPLY VOLTAGE (5V ±10%) VCC VCC VCC VCC DS3991 ANALOG LAMP BRIGHT BRIGHTNESS CONTROL PWM_EN SLOPE LOSC RESISTOR SET LAMP FREQUENCY PWM LAMP BRIGHTNESS POSC/PWM CONTROL (OPTIONAL) RESISTOR SET BURST-DIMMING FREQUENCY 12 ______________________________________________________________________________________ Typical Operating Circuits ...
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DEVICE SUPPLY VOLTAGE (5V ±10%) VCC VCC VCC VCC DS3991 ANALOG LAMP BRIGHT BRIGHTNESS CONTROL PWM_EN SLOPE LOSC RESISTOR SET LAMP FREQUENCY PWM LAMP BRIGHTNESS POSC/PWM CONTROL (OPTIONAL) RESISTOR SET BURST-DIMMING FREQUENCY ______________________________________________________________________________________ Low-Cost CCFL Controller Typical Operating Circuits (continued) ...
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Low-Cost CCFL Controller OFF/RESET = CLOSED DEVICE SUPPLY VOLTAGE (5V ±10%) VCC SVML VCC VCC VCC SVMH DUAL POWER MOSFET DS3991 GA ANALOG LAMP BRIGHT BRIGHTNESS CONTROL GB PWM_EN SLOPE LCM LOSC RESISTOR SET LAMP FREQUENCY POSC/PWM RESISTOR SET BURST-DIMMING ...
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Typical Half-Bridge Application, Multiple Lamps Per Channel ON = OPEN OFF/RESET = CLOSED DEVICE SUPPLY VOLTAGE (5V ±10%) VCC SVML VCC VCC VCC SVMH DS3991 GA ANALOG LAMP BRIGHT BRIGHTNESS CONTROL GB PWM_EN SLOPE LCM LOSC RESISTOR SET LAMP FREQUENCY ...
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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. 16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2008 Maxim Integrated Products ...