LM3502ITL-44EV National Semiconductor, LM3502ITL-44EV Datasheet
LM3502ITL-44EV
Specifications of LM3502ITL-44EV
Related parts for LM3502ITL-44EV
LM3502ITL-44EV Summary of contents
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... LM3502 offers superior performance over other application specific standard product step-up white LED drivers. Typical Application FIGURE 1. Blacklight Configuration with 10 White LEDs © 2006 National Semiconductor Corporation Features n Drive white LEDs for Dual Display Backlighting > ...
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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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... LM3502SQ-16 16 LM3502SQX-16 25 LM3502ITL-25 25 LM3502ITLX-25 25 LM3502SQ-25 25 LM3502SQX-25 35 LM3502ITL-35 35 LM3502ITLX-35 35 LM3502SQ-35 35 LM3502SQX-35 44 LM3502ITL-44 44 LM3502ITLX-44 44 LM3502SQ-44 44 LM3502SQX-44 En1 (Bump A2): Enable pin for the internal PMOS FET switch (Figure 2: P1) during device operation. When V ≤ 0.3V, the internal PMOS FET switch turns on and the MAIN is ≥ ...
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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 Dissipation Maximum Junction Temperature (T J-MAX) Storage Temperature Range Preliminary Electrical Characteristics Limits in bold typeface apply over the full operating junction temperature range (− ...
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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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