LTM8042EV-1PBF LINER [Linear Technology], LTM8042EV-1PBF Datasheet

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FEATURES n True Color PWM™ with 3000:1 Dimming Ratio n Operates in Boost, Buck Mode or Buck-Boost Mode n Wide Input Voltage Range: Operation from 3V to 30V Transient Protection to 40V n Gate Driver for Optional PWM Dimming with ...

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... LTM8042EV#PBF LTM8042EV#PBF LTM8042IV#PBF LTM8042IV#PBF LTM8042EV-1#PBF LTM8042EV-1#PBF LTM8042IV-1#PBF LTM8042IV-1#PBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: This product is only offered in trays. For more information go to: ...

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ELECTRICAL CHARACTERISTICS operating temperature range, otherwise specifications are at T SYMBOL PARAMETER V Minimum Input DC Voltage CC(MIN) I LTM8042 LED Current LED LTM8042-1 LED Current V Open LED Clamp Voltage CLAMP ΔI /I Output Current Line Regulation OUT OUT ...

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LTM8042/LTM8042-1 TYPICAL PERFORMANCE CHARACTERISTICS LTM8042 Efficiency Boost Operation LED String (V) IN 80421 G01 Efficiency Boost ...

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TYPICAL PERFORMANCE CHARACTERISTICS LTM8042 Efficiency Buck Mode, IN 10. LED String (V) ...

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LTM8042/LTM8042-1 TYPICAL PERFORMANCE CHARACTERISTICS LTM8042 Maximum LED Current Buck Mode IN 1000 900 800 700 600 500 400 300 200 100 (N) IN LED Current vs CTL Voltage 100 80 ...

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TYPICAL PERFORMANCE CHARACTERISTICS LTM8042 Junction Temperature Rise vs Load, Buck Mode, 2. LED String 24V 12V 200 400 600 800 LED CURRENT (mA) 80421 G26 ...

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LTM8042/LTM8042-1 TYPICAL PERFORMANCE CHARACTERISTICS LTM8042 Junction Temperature Rise vs Load, Buck-Boost Mode, 10. LED String 12V 200 400 600 800 LED CURRENT (mA) 80421 G35 ...

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TYPICAL PERFORMANCE CHARACTERISTICS LTM8042-1 Efficiency Boost Operation, IN 15.6V at 350mA LED String (V) IN 80421 G42 ...

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LTM8042/LTM8042-1 TYPICAL PERFORMANCE CHARACTERISTICS LTM8042-1 Efficiency Buck Mode, IN 18.6V at 350mA LED String (V) IN 80421 G51 Efficiency ...

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TYPICAL PERFORMANCE CHARACTERISTICS LTM8042-1 Maximum LED Current vs Input Voltage, Buck-Boost Mode 400 350 300 250 200 150 3.2V AT 350mA 6.3V AT 350mA 100 9.4V AT 350mA 12.4V AT 350mA 50 15.5V AT 350mA 18.6V AT 350mA 0 0 ...

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LTM8042/LTM8042-1 TYPICAL PERFORMANCE CHARACTERISTICS LTM8042-1 Junction Temperature Rise vs Load, Buck Mode, 6.8V at 350mA LED String 12 10 24V 12V 100 150 200 250 300 LED CURRENT (mA) 80421 G69 ...

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TYPICAL PERFORMANCE CHARACTERISTICS LTM8042-1 Junction Temperature Rise vs Load, Buck-Boost Mode, 11.2V at 350mA LED String 12V 100 150 LED CURRENT (mA) PIN FUNCTIONS GND (Bank 1): ...

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LTM8042/LTM8042-1 PIN FUNCTIONS TG (Pin J7): Top Gate Driver Output. In response to an active high PWM signal, this pin will drive the gate of an external series P-channel MOSFET device low. An internal 7V clamp protects the PFET gate. ...

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OPERATION The LTM8042/LTM8042 complete, full featured, current mode regulator specifically designed to drive light emitting diodes (LEDs) or other loads where a constant cur- rent (350mA for the LTM8042-1) is required. The LTM8042/LTM8042-1 can operate ...

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LTM8042/LTM8042-1 APPLICATIONS INFORMATION For most applications, the design process is straight forward, summarized as follows: 1. Decide whether the LTM8042/LTM8042-1 should operate in boost, buck, or buck-boost mode. 2. Look at Tables 1 through 6 and find the line that ...

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APPLICATIONS INFORMATION Which mode to use depends upon the operating condi- tions. Boost is generally selected when the voltage across the LED string is always higher than the input voltage. Buck mode is the dual of boost, used when the ...

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LTM8042/LTM8042-1 APPLICATIONS INFORMATION PCB Layout Most of the headaches associated with PCB layout have been alleviated or even eliminated by the high level of integration of the LTM8042/LTM8042-1. The device is nevertheless a switching power supply, and care must be ...

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APPLICATIONS INFORMATION GND THERMAL VIAS TO GROUND PLANE TO LED STRING V C VCC GND THERMAL VIAS TO GROUND PLANE TO LED STRING C V OUT VCC C IN – BSTIN/BKLED V CC BSTOUT/BKIN GND R ...

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LTM8042/LTM8042-1 APPLICATIONS INFORMATION Table 1. LTM8042 Recommended Values and Configuration for Boost ( RANGE (BSTIN/ – BKLED ) V CC – 3.6V Connect to BSTIN/BKLED – 5.1V Connect to BSTIN/BKLED – 6.3V ...

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APPLICATIONS INFORMATION Table 2. LTM8042 Recommended Values and Configuration for Buck Mode (T V RANGE IN (BSTOUT/BKIN 4. 30V 1μF 0805 X7R 50V 6.8V to 14V 3V to 30V 1μF 0805 X7R ...

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LTM8042/LTM8042-1 APPLICATIONS INFORMATION Table 3. LTM8042 Recommended Values and Configuration for Buck-Boost Mode ( RANGE (BSTIN – BKLED ) GND 30V 1μF 0805 X7R 50V 1μF ...

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APPLICATIONS INFORMATION Table 4. LTM8042-1 Recommended Values and Configuration for Boost ( RANGE (BSTIN/ – BKLED ) 3. 30V 1. 30V 1. 30V 2.2V ...

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LTM8042/LTM8042-1 APPLICATIONS INFORMATION Table 5. LTM8042-1 Recommended Values and Configuration for Buck Mode (T V RANGE IN (BSTOUT/ BKIN 4. 30V 1μF 0805 X7R 50V 1μF 1206 X7R 50V 2.2μF 1206 X7R ...

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APPLICATIONS INFORMATION Table 6. LTM8042-1 Recommended Values and Configuration for Buck-Boost Mode (T V RANGE IN (BSTIN/ CV (BSTIN/BKLED CC – BKLED ) GND 9. 30V 1μF 0805 X7R 50V 1μF ...

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LTM8042/LTM8042-1 APPLICATIONS INFORMATION Thermal Considerations The LTM8042/LTM8042-1 output current may need to be derated required to operate in a high ambient tem- perature or deliver a large amount of continuous power. The amount of current derating is ...

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APPLICATIONS INFORMATION The most appropriate way to use the coefficients is when running a detailed thermal analysis, such as FEA, which considers all of the thermal resistances simultaneously. None of them can be individually used to accurately pre- dict the ...

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LTM8042/LTM8042-1 TYPICAL APPLICATIONS Buck-Boost Mode, Driving 5 White LEDs at 500mA with PWM Dimming 17.5V 19V TO 30V 6V TO 22V 28 LTM8042 + V LED CC RUN PWM TG TGEN BSTOUT/BKIN – SYNC BSTIN/BKLED SS ...

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PACKAGE DESCRIPTION PIN NAME PIN NAME A1 GND B1 GND A2 GND B2 GND A3 GND B3 GND A4 GND B4 GND A5 GND B5 GND PIN NAME PIN NAME ...

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LTM8042/LTM8042-1 PACKAGE DESCRIPTION bbb // 3.810 2.540 1.5875 1.270 0.9525 0.000 1.270 2.540 3.810 80421fa ...

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REVISION HISTORY REV DATE DESCRIPTION A 01/11 Updated features. Updated I conditions in the Electrical Characteristics section. LED Updated text in the Operation section. Updated text in the Setting the Switching Frequency section. Information furnished by Linear Technology Corporation is ...

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LTM8042/LTM8042-1 TYPICAL APPLICATION Boost Operation, Driving 9 Red LEDs at 350mA with Analog Dimming 24.8V RELATED PARTS PART NUMBER DESCRIPTION LTM8040 36V, 1A, μModule LED Driver and Current Source LTM8032 EMC 36V, 2A, μModule Regulator LTM4607 ...