lx1996 Microsemi Corporation, lx1996 Datasheet
lx1996
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lx1996 Summary of contents
Page 1
... PWM dimming and combination of analog and direct PWM dimming for 25000:1 dimming range. The LX1996 is designed to work over a wide input voltage range from 6V to 28Vdc with adjustable over protection (OVP), and short and open LED protection ...
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... LED outputs. With DSEL1 pin open and DSEL2 pin tied high, this pin is used as a sync input for synchronizing the LX1996’s internal PWM dimming clock with an external clock signal of 400ns or greater width. Current source setting resistor. Must be 100KΩ between this pin and ground when Analog to Digital Dimming ...
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... Copyright © 2007 Rev. 1.0, 2007-12-14 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Multi-string LED Back-light Controller ® Description Microsemi Analog Mixed Signal Group LX1996 D RODUCTION ATASHEET Page 3 ...
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... X CS OVER VOLTAGE LIMIT LED SHORT DETECTION CS OVER VOLTAGE ANALOG TO DIGITAL LED OPEN DIMMING DETECTION CS OPEN OUTPUT CONTROL OUTPUT ENABLE LOGIC Microsemi Analog Mixed Signal Group LX1996 P D RODUCTION ATASHEET DRV NGATE DRIVER OVP + - 2V GND CURRENT SOURCE CS6 OUTPUT #6 CURRENT SOURCE ...
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... RT = 100kΩ 200pF 100kΩ INTPWM CT =.047μ 100kΩ Percent of Internal PWM Frequency For synchronization TH_OVP Microsemi Analog Mixed Signal Group LX1996 P D RODUCTION ATASHEET < Temp <85 = 0.075Ω 4.7uF SRC OUTPUT LX1996 Min Typ Max 0.8V 2 2.4 0 -10 -4 1.2 1.6 2.0 2 ...
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... I ≤ 6.0mA in VLDO I External available current VLDO VLDO rising UVLO 1000pF; 10 RISE 1000pF; 90 FALL L Microsemi Analog Mixed Signal Group LX1996 P D RODUCTION ATASHEET 0 C < Temp <85 = 0.075Ω 4.7uF SRC OUTPUT 19.2 20 20 ...
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... 3V VIN , R = 4.99 kΩ, L=6.8μH, R PRG R =100KΩ, Ultrasonic mode T Max+I Min)/ Microsemi Analog Mixed Signal Group LX1996 P D RODUCTION ATASHEET < Temp <85 = 0.075Ω 4.7uF SRC OUTPUT 23 ...
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... Microsemi Analog Mixed Signal Group LX1996 P D RODUCTION ATASHEET Sleep current Vs input voltage Vin (V) Input Voltage 20.04mA SET Variation ILED1 Variation ILED2 Variation ILED3 ...
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... 17.5kHz, Digital dimming VCS 6X LED Current Inductor Current PWM Input USPS Operation; LED Current = 0.5mA Inductor Current Boost Output LED Current Microsemi Analog Mixed Signal Group LX1996 D ATASHEET Page 9 ...
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... Line Transient Response; VIN 20V to 10V Step Boost Output LED Current VIN LED Open Response Boost Current Boost Voltage Current Microsemi Analog Mixed Signal Group LX1996 D ATASHEET OVP THRESHOLD V OVP V BOOST V CS Page 10 ...
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... DPST PWM 4.7uF/6.3V,X7R 10 12 Figure 1 – Typical Application – This circuit demonstrates the LX1996 and LX1972 interfacing to the LX1800, which is an SMBus ADC/DAC. This application also uses the Display Power Saving Technology (DPST) signal. LX1996ILQ = Multi-string LED Back-light Controller, Microsemi ...
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... Direct Digital Dimming or Direct Analog PRG Dimming. In combined Analog and Digital Dimming with DI ≥ 2V. When DI < 2V, then IMMING The LX1996 offers 6 methods of dimming using only 2 pins (See Table 1 IRECT IGITAL The LED current source outputs are directly turned on and off by the PWM signal ...
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... Low Hi Hi Low Hi Hi Open Low Open Hi Microsemi Analog Mixed Signal Group LX1996 D ATASHEET Dimming Method Direct Digital Dimming Combined Analog and Digital Dimming Modes Direct Analog Dimming Direct Analog Dimming with Ultrasonic Pulse Skipping (USPS) Analog to Digital dimming with internal clock ...
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... DI 100Hz – 25kHz • • • • Microsemi Analog Mixed Signal Group LX1996 D ATASHEET Controller Performance PWM duty cycle controlled by the signal into the DI pin Signal into DI pin will be either from an Ambient Light Sensor (ALS variable voltage source will be in the range of 0 ...
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... LX1996’s OVP limit. The over-voltage threshold is set the OVP pin. When OVP limit threshold is met, the LX1996 will regulate the boost output to the OVP 2V threshold. OVP limit should be set to a voltage approximately 2 Volts above the maximum total V individual diode strings ...
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... STEP Maximum inductor peak current 150mA 50mA = 2.3A PEAK (MAX) The current sense signal is very sensitive; therefore, the LX1996 SRC pin must be connected directly to the junction of the sense resistor and the NFET Source, as close to R SRC practical. The return side of the sense resistor must tie directly to the PGND pin, and then tie the PGND pin to the ground plane ...
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... The LX1996 controls the off time and peak current for hysteretic PFM converter topology. vary proportionally with input voltage per the following ...
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... Copyright © 2007 Rev. 1.0, 2007-12-14 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Multi-string LED Back-light Controller ® P RODUCTION and gate ON Microsemi Analog Mixed Signal Group LX1996 D ATASHEET Page 18 ...
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... GND pin important that the LX1996 have a good thermal path to ambient to dissipate heat. The simplest way to do this is to heat sink the LX1996 bottom pad directly to the ground plane by placing 4 or more vias in the ground pad directly under the LX1996 footprint ...
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... PCB LAYOUT GUIDE – ILKSCREEN Copyright © 2007 Rev. 1.0, 2007-12-14 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Multi-string LED Back-light Controller ® AYER Microsemi Analog Mixed Signal Group LX1996 P D RODUCTION ATASHEET Page 20 ...
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... C2 C1 100k 2.2nF 8 18 0.1uF RT CS6 CS5 10 16 CLF CS4 11 15 PRG CS3 14 CS2 7 13 PWM CS1 Figure 2 – LX1996 Example Schematic Microsemi Analog Mixed Signal Group LX1996 D RODUCTION ATASHEET D1 1N5819 Powermite 4.7uF/50V 1206 68.1k 22.1k 0.075 ...
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... Multi-string LED Back-light Controller ® P RODUCTION Notes Controlled dimensions are in mm, inches are 2. Dimensions do not include mold flash or Microsemi Analog Mixed Signal Group LX1996 D ATASHEET M I ILLIMETERS NCHES Dim ...