LTM8040IV#PBF Linear Technology, LTM8040IV#PBF Datasheet
LTM8040IV#PBF
Specifications of LTM8040IV#PBF
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LTM8040IV#PBF Summary of contents
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... Display Backlighting n Constant Current Sources L, LT, LTC, LTM, μModule, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION 1A μModule LED Driver ...
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... LTM8040EV#PBF LTM8040EV#PBF LTM8040IV#PBF LTM8040IV#PBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ This product is only offered in trays ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER LEDA Clamp Voltage Minimum BIAS Voltage Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating ...
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LTM8040 TYPICAL PERFORMANCE CHARACTERISTICS otherwise noted) Minimum Running Voltage vs Output Voltage LOAD 4 0.5A LOAD 0.1A LOAD OUTPUT VOLTAGE (V) 8040 G08 SHDN Current vs Voltage ...
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TYPICAL PERFORMANCE CHARACTERISTICS otherwise noted) Temperature Rise vs Output Current (2. LEDs, 36V 27 SINGLE LED 2 LEDs 3 LEDs 22 4 LEDs 200 400 OUTPUT CURRENT (mA) Temperature Rise vs Output Current ...
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LTM8040 PIN FUNCTIONS LEDA (Bank 1): This pin is the regulated current source of the LTM8040. Connect the anode of the LED string to this pin. This voltage must be at least 2.5V for accurate current regulation. SHDN (Pin L4): ...
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BLOCK DIAGRAM V IN 0.1μF SHDN INTERNAL COMPENSATION PWM GND CURRENT MODE CONTROLLER 5.11k INTERNAL 80.6k 1.25V RT ADJ LTM8040 SENSE 8.2μH RESISTOR LEDA 4.7μF LPWR BIAS 8040 BD 8040fa 7 ...
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LTM8040 OPERATION The LTM8040 is a constant frequency, current mode converter capable of generating a constant 1A output intended to drive LEDs or other applications where a constant current is required. Operation can be best understood by referring to the ...
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APPLICATION INFORMATION For most applications, the design process is straight forward, summarized as follows: 1. Look at Table 2 and fi nd the row that has the desired input voltage range LED string voltage range and output current. 2. Apply ...
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LTM8040 APPLICATION INFORMATION If another frequency is desired, Table 1 shows suggested R selections for a variety of switching frequencies. T Table Frequency T R (kΩ) FREQUENCY (MHz 18.7 24.9 29.4 35.7 54.9 75 ...
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APPLICATION INFORMATION Programming LED Current The LED current can be set by adjusting the voltage on the ADJ pin. The ADJ pin is internally pulled precision 1.25V voltage source through a 5.11k 1% resistor. This resistor makes ...
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LTM8040 APPLICATION INFORMATION PWM dimming control (Figure 5) uses the PWM pin and an external NFET tied to the cathode of the LED. When the PWM signal goes low, the NFET turns off, disconnecting the LED from the internal current ...
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APPLICATION INFORMATION Capacitor Selection Considerations The C capacitor values in Table 2 are the minimum rec- IN ommended values for the associated operating conditions. Applying capacitor values below those indicated in Table 2 is not recommended, and may result in ...
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LTM8040 APPLICATION INFORMATION Layout Hints Most of the headaches associated with PCB layout have been alleviated or even eliminated by the high level of integration of the LTM8040. The LTM8040 is neverthe- less a switching power supply, and care must ...
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APPLICATION INFORMATION Table 2. Recommended Confi guration LED STRING VOLTAGE V RANGE C (LEDA 4.5V to 36V 1μF 0805 50V 2. 6.5V to 36V 1μF 0805 50V 9.5V to 36V 1μF 0805 50V ...
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LTM8040 TYPICAL APPLICATIONS 5.5V TO 24V *RUNNING VOLTAGE. SEE APPLICATION INFORMATION FOR START-UP REQUIREMENTS 10.5V TO 36V *RUNNING VOLTAGE. SEE APPLICATION INFORMATION FOR START-UP REQUIREMENTS 16 Step Down 1A Drive with Single Red or White LED LTM8040 ...
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TYPICAL APPLICATIONS 15.5V TO 36V *RUNNING VOLTAGE. SEE APPLICATION INFORMATION FOR START-UP REQUIREMENTS 15.5V TO 36V *RUNNING VOLTAGE. SEE APPLICATION INFORMATION FOR START-UP REQUIREMENTS Step Down 1A Drive with Three White Series LEDs LTM8040 LEDA IN ...
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LTM8040 PACKAGE DESCRIPTION Z aaa bbb 6.350 5.080 3.810 2.540 1.5875 1.270 0.9525 0.000 1.270 2.540 3.810 5.080 6.350 8040fa ...
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... G7 GND Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. Pin Assignment Table (Arranged by Pin Number) ...
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... DC/DC μModule IN LTM8020 36V, 200mA DC/DC μModule LTM8022 1A, 36V DC/DC μModule LTM8023 2A, 36V DC/DC μModule PolyPhase is a registered trademark of Linear Technology Corporation Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 COMMENTS Basic 10A DC/DC μModule, 15mm × 15mm × 2.8mm LGA – ...