ZXLD1350ET5TA Diodes Zetex, ZXLD1350ET5TA Datasheet
ZXLD1350ET5TA
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ZXLD1350ET5TA Summary of contents
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Description The ZXLD1350 is a continous mode inductive step-down converter with integrated switch and high side current sense. It operates from an input supply from 7V to 30V driving single or multiple series connected LEDs effeciently external adjustable output current ...
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Block Diagram ADJ Vref GND Figure 1. Block diagram – Pin Connection for TSOT Package Pin Description Pin Name No Drain of NDMOS switch GND 2 Ground (0V) Multi-function On/Off and brightness control pin: • ...
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Absolute Maximum Ratings Symbol Parameter V Input Voltage Voltage SENSE SENSE V LX Output Voltage LX V Adjust Pin Input Voltage ADJ I Switch Output Current LX Power Dissipation P TOT (Refer to Package thermal de-rating curve ...
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Electrical Characteristics Symbol Parameter V Internal regulator start-up threshold SU I Quiescent supply current with output off INQoff I Quiescent supply current with output switching INQon Mean current sense threshold voltage V SENSE (Defines LED current setting accuracy) V Sense ...
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Device Description The device, in conjunction with the coil (L1) and current sense resistor (R converter. Device operation (Refer to block diagram and Figure 1 - Operating waveforms) Operation can be best understood by assuming that the ADJ pin of ...
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Device Description (Continued) ZXLD1350 Document number: DS33468 Rev Figure 1. Theoretical Operating Waveforms www.diodes.com A Product Line of Diodes Incorporated ZXLD1350 March 2011 © Diodes Incorporated ...
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Device Description (Continued) Typical Operating Waveforms [V Normal operation. Output current (Ch3) and LX voltage (Ch1) Start-up waveforms. Output current (Ch3), LX voltage (Ch1) and V ZXLD1350 Document number: DS33468 Rev 0.3V 100 μH] ...
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Typical Operating Conditions ZXLD1350 Document number: DS33468 Rev Product Line of Diodes Incorporated www.diodes.com ZXLD1350 March 2011 © Diodes Incorporated ...
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Typical Characteristics (Continued) ZXLD1350 Document number: DS33468 Rev Product Line of Diodes Incorporated www.diodes.com ZXLD1350 March 2011 © Diodes Incorporated ...
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Typical Characteristics (Continued) ZXLD1350 Document number: DS33468 Rev Product Line of Diodes Incorporated www.diodes.com ZXLD1350 March 2011 © Diodes Incorporated ...
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Typical Characteristics (Continued) ZXLD1350 Document number: DS33468 Rev Product Line of Diodes Incorporated www.diodes.com ZXLD1350 March 2011 © Diodes Incorporated ...
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Application Information Setting nominal average output current with external resistor R The nominal average output current in the LED(s) is determined by the value of the external current sense resistor (R connected between V and I and is given by: ...
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Application Information (Continued) Output Current Adjustment by PWM Control Directly driving ADJ input A Pulse Width Modulated (PWM) signal with duty cycle D output current to a value above or below the nominal average value set by resistor R PWM ...
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Application Information (Continued) Low frequency PWM mode When the ADJ pin is driven with a low frequency PWM signal (eg 100Hz), with a high level voltage V zero, the output of the internal low pass filter will swing between 0V ...
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Application Information (Continued) High frequency PWM mode At PWM frequencies above 10kHz and for duty cycles above 0.16, the output of the internal low pass filter will contain a DC component that is always above the shutdown threshold. This will ...
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Application Information (Continued) Soft-start The device has inbuilt soft-start action due to the delay through the PWM filter. An external capacitor from the ADJ pin to ground will provide additional soft-start delay, by increasing the time taken for the voltage ...
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Application Information (Continued) Inductor Selection Recommended inductor values for the ZXLD1350 are in the range 47mH to 220mH. Higher values of inductance are recommended at higher supply voltages in order to minimize errors due to switching delays, which result in ...
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Application Information (Continued) Example: For V =12V, L=47mH, rL=0.64V LED T = (47e-6 x 0.105)/(12 - 3.4 - 0.672) = 0.622ms (47e-6 x 0.105)/(3.4 + 0.36 + 0.322)= 1.21ms OFF This gives an operating frequency ...
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Application Information (Continued) Reducing Output Ripple Peak to peak ripple current in the LED(s) can be reduced, if required, by shunting a capacitor Cled across the LED(s) as shown below value of 1μF will reduce nominal ripple ...
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Application Information (Continued) Thermal compensation of output current High luminance LEDs often need to be supplied with a temperature compensated current in order to maintain stable and reliable operation at all drive levels. The LEDs are usually mounted remotely from ...
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... Ordering Information Part Package Device Code Mark ZXLD1350ET5TA 1350 ET5 Package Outline Dimensions TSOT23-5 ZXLD1350 Document number: DS33468 Rev Reel Packaging Reel size width (mm) (Note 4) (mm) TSOT23-5 180 www.diodes.com A Product Line of Diodes Incorporated ZXLD1350 AEC-Q100 Part Number Quantity Level per reel ...
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DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY ...