lm27961tlx National Semiconductor Corporation, lm27961tlx Datasheet
lm27961tlx
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lm27961tlx Summary of contents
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... The LM27961 is available in National’s chip-scale 18-bump micro SMD package. Typical Application Circuit © 2004 National Semiconductor Corporation Features n Drives 4 Individual Common-Anode LEDs with up to 20mA each for a Main Display Backlight n Drives 3 Individual Common-Cathode LEDs with up to ...
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... Ordering Information Order Information LM27961TL LM27961TLX www.national.com 18-Bump Thin Micro SMD Package, Large Bump NS Package Number TLA18 Input voltage. Input range: 2.7V to 5.5V. Ground Charge pump output. Approximately 1.5xV Flying capacitor connections. LED Outputs - Group A LED Outputs - Group B Enable for Group-A LEDs (current outputs). Logic input. ...
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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. V pin voltage IN ENA, ENB pin voltages I Pin Voltages Dxx Continuous Power Dissipation (Note 3) Junction Temperature ...
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Electrical Characteristics Limits in standard typeface are for T less otherwise specified 3.6V 1.5V 8.35kΩ; C SETA SETB IN pins (I and I ) apply to both Group A and Group B. ...
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Typical Performance Characteristics = 3.6V; ENA = V and ENB = GND, or ENA = GND and ENB = V IN 1µF. LED Current (D1A, D2A,D3A, D4A) vs. Input Voltage Quiescent Current vs. Input Voltage, Unless otherwise specified ...
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Typical Performance Characteristics = 3.6V; ENA = V and ENB = GND, or ENA = GND and ENB = V IN 1µF. (Continued) Charge Pump Output Voltage vs. Output Current Input Current vs. Input Voltage www.national.com Unless otherwise specified: V ...
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Typical Performance Characteristics = 3.6V; ENA = V and ENB = GND, or ENA = GND and ENB = V IN 1µF. (Continued) Charge Pump Switching Frequency vs. Input Voltage Diode Current (DxB) vs. Headroom Voltage (DxB) Unless otherwise specified: ...
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Typical Performance Characteristics = 3.6V; ENA = V and ENB = GND, or ENA = GND and ENB = V IN 1µF. (Continued) Diode Current (DxA) vs. R SETx ENx Signal (Top) and Charge Pump Start-Up (Bottom) Waveforms Vertical Scale ...
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Block Diagram Circuit Description OVERVIEW The LM27961 is primarily intended for Lithium-Ion battery driven white-LED drive applications, and is well suited to drive white LEDs that are used for backlighting small-format displays. The part has seven matched constant-current out- puts, ...
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Circuit Description (Continued) anode outputs and a group of 3 common cathode outputs. There is an ON/OFF control pin for each group (ENA and ENB). The DC current through the LEDs is programmed with an external resistor. Changing currents on-the-fly ...
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Circuit Description (Continued) FIGURE 2. One Parallel Connected LED Connecting outputs in parallel does not affect internal opera- tion of the LM27961 and has no impact on the Electrical Characteristics and limits previously presented. The avail- able diode output current, ...
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Applications Information The voltage rating of the output capacitor should be 10V or more. All other capacitors should have a voltage rating at or above the maximum input voltage of the application. CIRCUIT BOARD LAYOUT For optimal, low-noise performance, all ...
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Physical Dimensions inches (millimeters) unless otherwise noted TLA18EHA: 18-Bump Thin Micro SMD, Large Bump National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time ...