ZXLD1360ET5TA Diodes Zetex, ZXLD1360ET5TA Datasheet

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Description The ZXLD1360 is a continuous 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 efficiently externally adjustable output current ...

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Block Diagram 4.7µF ADJ 3 200k 1.25V GND 2 Figure 1. Block diagram – With Pin Connections Pin Descriptions Name Pin No Drain of NDMOS switch GND 2 Ground (0V) Multi-function On/Off and brightness control ...

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Absolute Maximum Ratings Symbol 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 on ...

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Electrical Characteristics (Test conditions: V Symbol Parameter V Internal regulator start-up threshold SU V Internal regulator shutdown threshold SD I Quiescent supply current with output off INQoff I Quiescent supply current with output switching INQon Mean current sense threshold voltage ...

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Device Description The device, in conjunction with the coil (L1) and current sense resistor (RS), forms a self-oscillating continuous-mode buck converter. Device operation (refer to Figure 1 - Block diagram and Figure 2 Operating waveforms) Operation can be best understood ...

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Device Description voltage SENSE voltage Coil current 0V Comparator V input voltage ADJ 5V Comparator output 0V ZXLD1360 Document number: DS33471 Rev Toff Ton 115mV 85mV 0.15V ADJ Figure 2. Operating ...

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Device Description (cont.) Actual operating waveforms [V IN Normal operation. Output current (Ch1) and LX voltage (Ch2) Actual operating waveforms [V IN Normal operation. Output current (Ch1) and LX voltage (Ch2) ZXLD1360 Document number: DS33471 Rev =15V, ...

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Typical Operating Characteristics ZXLD1360 Output C urrent L = 33µH 1060 1040 1020 1000 980 960 940 920 900 Supply Voltage LED 2 LED s 3 LED s 4 LED s 5 ...

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Typical Operating Characteristics ZXLD1360 Output Current L = 47µH 1060 1040 1020 1000 980 960 940 920 900 Supply Voltage LED 2 LED s 3 LED s 4 LED s 5 LED ...

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Typical Operating Characteristics ZXLD1360 Output Current L = 100µH 1060 1040 1020 1000 980 960 940 920 900 Supply Voltage LED 2 LED s 3 LED s 4 LED s 5 LED ...

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Typical Operating Characteristics 1.4 1.2 1 0.8 0.6 0.4 0 Supply Voltage V V vs. Supply Voltage REF 600 500 400 300 200 100 Supply Voltage V IN ...

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Typical Operating Characteristics ZXLD1360 Response Time vs. Temperature Ty pical minimum LX ‘on’ and ‘off’ t ime 350 300 250 200 150 100 50 0 -55 -35 - Ambient Temperature ( C) Min Min ...

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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 (cont.) 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   V ADJ ADJ 0V GND ...

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Application Information (cont.) Shutdown Mode Taking the ADJ pin to a voltage below 0.2V for more than approximately 100µs will turn off the output and supply current to a low standby level of 20µA nominal. Note that the ADJ pin ...

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Application Information (cont.) This time has been extended on the trace below by adding a 100nF ceramic capacitor which gives a soft start time of 40 milliseconds approximately. Actual operating waveforms [V =15V Soft-start operation. Output current (CH2) ...

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Application Information (cont.) Inductor Selection Recommended inductor values for the ZXLD1360 are in the range 33µH to 100µH. 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 (cont.) Example: For V =12V, L=33µH, rL=0.093, R =0.1Ω (33e-6 x 0.3)/(12 - 3.6 - 0.693) = 1.28µ (33e-6 x 0.3)/(3.6 + 0.49 + 0.193) = 2.31µs OFF This ...

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Application Information (cont.) 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 ...

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Application Information (cont.) Thermal considerations When operating the device at high ambient temperatures, or when driving maximum load current, care must be taken to avoid exceeding the package power dissipation limits. The graph below gives details for power derating. This ...

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Application Information (cont.) Layout Considerations LX pin The LX pin of the device is a fast switching node, so PCB tracks should be kept as short as possible. To minimize ground 'bounce', the ground pin of the device should be ...

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Application Information (cont.) Dimming output current using PWM Low frequency PWM mode When the ADJ pin is driven with a low frequency PWM signal (eg 100Hz), with a high level voltage VADJ and a low level of zero, the output ...

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Application Information (cont.) 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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... Ordering Information Part Package Device Code Mark ZXLD1360ET5TA 1360 ET5 Package Outline Diminsions TSOT23 ZXLD1360 Document number: DS33471 Rev Packaging Reel size Reel width (mm) (mm) (Note 4) TSOT23-5 180 θ L θ www.diodes.com A Product Line of Diodes Incorporated ZXLD1360 Part Number Quantity AEC-Q100 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 ...