LM3502ITL-16 NSC [National Semiconductor], LM3502ITL-16 Datasheet
LM3502ITL-16
Related parts for LM3502ITL-16
LM3502ITL-16 Summary of contents
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LM3502 Step-Up Converter for White LED Applications General Description The LM3502 is a white LED driver for lighting applications. For dual display or large single white LED string backlighting applications, the LM3502 provides a complete solution. The LM3502 contains two ...
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Connection Diagrams 10-Bump Thin MicroSMD Package (TLP10) TOP VIEW Pin Descriptions/Functions Bump # Pin # Name A1 9 Cntrl OUT2 OUT1 D2 2 and and 16 PGND ...
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... I shutdown mode of operation where all the Q internal FET switches are off not used, En2 must OUT2 be grounded or floating and use En1 along with Cntrl, to enable the device. Ordering Information Voltage Option Order Number 16 LM3502ITL-16 16 LM3502ITLX-16 16 LM3502SQ-16 16 LM3502SQX-16 25 LM3502ITL-25 25 LM3502ITLX-25 25 ...
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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 IN Sw Pin Fb Pin Cntrl Pin V Pin OUT1 V Pin OUT2 En1 En2 Continuous Power ...
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Preliminary Electrical Characteristics Limits in bold typeface apply over the full operating junction temperature range (−40˚C ≤ T specified 2.5V. (Continued) IN Symbol Parameter I (ON) V Pin Bias V V OUT1 OUT1 OUT1 Current (Note 3) V ...
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Block Diagram www.national.com FIGURE 2. Block Diagram 6 20131704 ...
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Detailed Description of Operation The LM3502 utilizes an asynchronous current mode pulse- width-modulation (PWM) control scheme to regulate the feedback voltage over specified load conditions. The DC/DC converter behaves as a controlled current source for white LED applications. The operation ...
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FIGURE 3. Operational Characteristics Table 20131706 FIGURE 4. Control Signal Waveform 8 20131705 ...
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Typical Performance Characteristics Efficiency: η [(V – V OUT IN OUT Fb I (Non-Switching (Switching LED Efficiency vs LED Current ( Circuit in Figure DO1608C-223 ...
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Typical Performance Characteristics Efficiency: η [(V – V OUT IN OUT 6 LED Efficiency vs LED Current Cntrl Pin Current vs Cntrl Pin Voltage En1 Pin Current vs En1 Pin Voltage www.national.com ( Circuit in Figure ...
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Typical Performance Characteristics Efficiency: η [(V – V OUT IN OUT Fb V Pin Current vs V OUT1 OUT1 NMOS R (Figure 2: N2 DS(ON) Feedback Voltage vs Temperature ( Circuit in Figure 1: ...
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Typical Performance Characteristics Efficiency: η [(V – V OUT IN OUT Current Limit (LM3502-16 Current Limit (LM3502-25 Current Limit (LM3502-35/44) vs Temperature www.national.com ( Circuit in Figure DO1608C-223 and ...
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Application Information WHITE LED CURRENT SETTING The LED current is set using the following equation: 20131730 I : White LED Current. LED V : Feedback Pin Voltage 0.25V, Typical R1: Currrent Setting Resistor. WHITE LED DIMMING ...
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Application Information CONTINUOUS AND DISCONTINUOUS MODES OF OPERATION Since the LM3502 is a constant frequency pulse-width- modulated step-up regulator, care must be taken to make sure the maximum duty cycle specification is not violated. The duty cycle equation depends on ...
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Application Information D: Duty Cycle for DCM Operation Output Voltage. OUT V : Input Voltage White LED Current/Load Current. OUT Fs: Switching Frequency. L: Inductor Value/Inductance Magnitude. INDUCTOR SELECTION In order to maintain inductance, an ...
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Application Information Taiyo GMK212BJ105MD Yuden (0805/35V) muRata GRM40-035X7R105K (0805/50V) TDK C3216X7R1H105KT (1206/50V) C3216X7R1C475K (1206/16V) AVX 08053D105MAT (0805/25V) 08056D475KAT (0805/6.3V) 1206ZD475MAT (1206/10V) DIODE SELECTION To maintain high efficiency it is recommended that the aver- age current rating ( ...
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Physical Dimensions inches (millimeters) unless otherwise noted 16-Lead Thin Leadless Leadframe Package NS Package Number SQA16A TLP10: 10-Bump Thin Micro SMD X1 = 1.958 2.135 0 Package No. TLP10 17 www.national.com ...
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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 without notice to change said circuitry and specifications. For the most current product information ...