LM27952SD/NOPB National Semiconductor, LM27952SD/NOPB Datasheet
LM27952SD/NOPB
Specifications of LM27952SD/NOPB
LM27952SDTR
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LM27952SD/NOPB Summary of contents
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... LM27952 consumes less than 1µA of supply current when shut down. The LM27952 is available in a 14-pin No-Pullback Leadless Leadframe Package: LLP-14. Typical Application Circuit © 2005 National Semiconductor Corporation Features n Drives LEDs with up to 30mA each n Regulated current sources with 0.2%(typ.) matching n 3/2x, 1x Gain transition based on LED V n Peak Efficiency Over 85% n Input Voltage Range: 3 ...
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Connection Diagram 14-pin No-Pullback Leadless Leadframe Package (LLP-14) Pin Description Pin Name 1 C2 OUT 3 C1 SET PWM C2- 13 ...
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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 EN, PWM Continuous Power Dissipation (Note 3) Junction Temperature (T ) J-MAX-ABS Storage Temperature Range Lead Temp. (Soldering, 5 sec.) ESD Rating (Note 4) Human Body Model ...
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Electrical Characteristics Limits in standard typeface are for T range (-40˚C to +85 ˚C). Unless otherwise noted, specifications apply to the LM27952 Typical Application Circuit (pg.1) with V = 3.6V, V(EN) = 1.8V, V(PWM) = 1.8V, 4 LEDs, V Symbol ...
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Block Diagram 5 20148003 www.national.com ...
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Typical Performance Characteristics V = 3.6V PWM IN tors (MLCC’s). LED Current Regulation vs. Input Voltage Average LED Current Regulation vs. Input Voltage Efficiency vs. Input Voltage www.national.com ...
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Typical Performance Characteristics V = 3.6V PWM IN 1 capacitors (MLCC’s). (Continued) LED Current vs. V Input and Output Voltage Ripple V = 3.6V, Load = 15mA/LED, 4 ...
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Application Information CIRCUIT DESCRIPTION The LM27952 is an adaptive 1.5x/1x CMOS charge pump, optimized for driving white LEDs used in backlighting small- format displays. It provides four constant current inputs ca- pable of sinking up to 30mA through each LED. ...
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Application Information The equation below can be used to estimate the total output current capability of the LM27952 ((1 (( LED_MAX IN LED I = ((1 ...
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... National highly recommends a 1:1 ratio between the pack- age and the PCB thermal land. To further enhance thermal conductivity, the PCB thermal land may include vias to a ground plane. For more detailed instructions on mounting LLP packages, please refer to National Semiconductor Ap- plication Note AN-1187. 10 ...
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