LM3464MHX National Semiconductor Corporation, LM3464MHX Datasheet
LM3464MHX
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LM3464MHX Summary of contents
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... Protection features include VIN under-voltage lock-out, LED open/short circuit and over-temperature fault signaling to the system controller. Typical Application © 2010 National Semiconductor Corporation LM3464 Features ■ Wide input voltage range (12V-80V) ■ ...
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... Connection Diagram Ordering Information Order Number LM3464MH Exposed Pad TSSOP-28 LM3464MHX www.national.com Package Type NSC Package Drawing MXA28A 2 30115002 Supplied As 73 Units per Anti-Static Tube 2500 Units on Tape and Reel ...
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Pin Descriptions Pin Name Description 1 SYNC Synchronization signal output for cascade operation (Master-Slave configuration) 2 DIM PWM dimming control 3 Thermal Thermal sensor input 4 Thermal_Cap Thermal dimming ramp capacitor 5 VDHC Head room control 6 DMIN Minimum thermal ...
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Pin Name Description 20 SE4 Channel 4 sense input 21 GD4 Channel 4 gate driver output 22 PGND Power Ground 23 GD3 Channel 3 gate driver output 24 SE3 Channel 3 sense input 25 GD2 Channel 2 gate driver output ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications GND IN DR1, DR2, DR3, DR4 to GND EN to GND All other inputs to GND ESD ...
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Symbol Parameter Fault Detection V DRx short fault threshold SHORTFAULT V SEx open fault threshold OPENFAULT I FAULT_CAP pin output current FAULT-CAP V FAULT-CAP pin voltage threshold at fault FAULT-CAP timer expire R Faultb pin to GND resistance Faultb Thermal ...
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Typical Performance Characteristics application for driving twelve power LEDs with four output channels active and output current per channel = 350 mA. T unless otherwise specified. Channel 1 Current Sense Voltage (V Thermal_Cap Pin Output Current Operating Current (EN pin ...
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Startup Waveforms PWM Dimming Delay Time (V ) rising) DIM Thermal Foldback Dimming (V ) rising) THERMAL www.national.com PWM Dimming (DIM pin) 30115023 PWM Dimming Delay Time 30115025 Thermal Foldback Dimming 30115027 8 30115024 (V ) falling) DIM 30115044 (V ...
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Block Diagram 9 30115021 www.national.com ...
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FIGURE 1. Typical Application Circuit with Fly-Back AC/DC Converter Overview The LM3464 is a linear current regulator with four output channels designed for LED lighting systems with wide input voltage range, high speed PWM and thermal foldback dim- ming control ...
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System Operation In order to provide failure protection to the LEDs, the rail volt- age is pulled up by the LM3464 from a relatively low voltage level until reaching certain preset level. Figure 3 shows the change of the rail ...
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As the system enters steady state, the rail voltage V creases and finally settles to an optimal level that maintains the maximum power efficiency of the entire system. The volt- age level of V under steady state can be calculated ...
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RESPONSE OF THE LM3464 DRIVER STAGE In order to ensure good operation stability of the entire sys- tem, the response of the LM3464 circuitry must be set slower than the primary power supply. The response of the LM3464 is decided ...
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Thermal-foldback LED_ON Thermal-foldback = [(V - 0.4) X 35]% THERMAL ≤ for 0.4 V THERMAL SETTING MINIMUM THERMAL DIMMING DUTY CYCLE In applications that need to guarantee minimum illumines un- der high temperature environments, the ...
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V slowly. The V RAIL(nom) maintain operation to supply power and bias for external cir- cuitries. When the EN pin is released (floating), the LM3464 ...
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Additional Application Circuit www.national.com 16 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 28-Lead eTSSOP Package NS Package Number MXA28A 17 www.national.com ...
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