ZXLD1374_11 DIODES [Diodes Incorporated], ZXLD1374_11 Datasheet

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Description The ZXLD1374 is a 60V LED driver with integrated 1.5A low side switch to drive high current LEDs multi-topology converter enabling it to operate in Buck, Boost and Buck-boost configurations; efficiently controlling the 16 series connected ...

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Pin Descriptions Pin Type Pin Name (Note 2) Adjust input (for dc output current control) Connect to REF to set 100% output current. Drive with dc voltage (125mV<V ADJ 1 I set value. The ADJ pin has an internal clamp ...

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Absolute Maximum Ratings Symbol Parameter V Input supply voltage relative to GND IN V Auxiliary supply voltage relative to GND AUX V Current monitor input relative to GND ISM V Current monitor sense voltage (V SENSE V Low side switch ...

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Recommended Operating Conditions Symbol Parameter V Input supply voltage range IN V Auxiliary supply voltage range (Note 6) AUX V Differential input voltage SENSE V Low side switch output voltage LX I Low side switch continuous output current LX External ...

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Electrical Characteristics (Test conditions: V Symbol Parameter Supply and reference parameters Under-Voltage detection threshold V UV- Normal operation to switch disabled Under-Voltage detection threshold V UV+ Switch disabled to normal operation I Quiescent current into V Q- Quiescent ...

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Electrical Characteristics ( Test conditions: V Symbol Parameter Output Parameters V FLAG pin low level output voltage FLAGL I FLAG pin open-drain leakage current FLAGOFF STATUS Flag no-load output voltage V STATUS (Note 9) R Output impedance of STATUS output ...

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Typical Characteristics 3 2.5 2 1 Supply Voltage (V) Figure 1. Supply Current vs. Supply Voltage 700 650 600 550 500 450 400 I 350 Switching 300 Frequenc y 250 ...

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Typical Characteristics 100% 80% 60% 40% 20 250 500 750 T Pin Voltage (mV) ADJ Figure 7. LED Current vs. T 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -40 -25 - ...

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Typical Characteristics – Buck Mode – 25° AUX 33µH 1.60 Ω 146m S 1.55 1.50 1.45 1 LED 1.40 1. 1200 T = 25°C A ...

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Typical Characteristics – Buck Mode – R 0.825 T = 25° AUX 33µH 0.800 Ω 291m S 3 LEDs 0.775 1 LED 0.750 0.725 0.700 0.675 6 12 1000 T = ...

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Typical Characteristics – Boost mode – R 0.358 0.347 0.336 0.325 0.314 6 LED s 8 LED s 0.303 0.292 12 17 700 650 600 550 500 450 400 350 300 6 LED s 250 200 12 17 100% 6 ...

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Typical Characteristics – Boost mode – R 0.385 0.368 0.350 0.333 0.315 6.5 8 700 600 500 400 300 200 ° 33µH Ω 150m 100 S Ω ...

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Typical Characteristics – Buck-boost mode – R 0.385 0.375 0.365 0.355 0.345 0.335 0.325 0.315 6.5 8.0 600 500 400 300 200 100 0 6.5 8.0 Figure 24. Switching Frequency vs. Input Voltage and Number of LED 100% ° T ...

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Applications Information The ZXLD1374 is a high accuracy hysteretic inductive Buck/Boost/Buck-boost converter with an internal NMOS switch designed to be used for current-driving single or multiple series-connected LEDs. The device can be configured to operate in Buck, Boost, or Buck-boost ...

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Applications Information (Continued) b) Boost and Buck-boost modes A basic ZXLD1374 application circuit for Buck-boost and Boost modes is shown in Figure 28. Control in Boost and Buck-boost mode is achieved by sensing the coil current in the series resistor ...

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Applications Information (Continued) Component Selection External component selection is driven by the characteristics of the load and the input supply, since this will determine the kind of topology being used for the system. Component selection starts with the current setting ...

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Applications Information (Continued) When the ADJ pin is directly connected to the REF pin, this becomes: Note that the average LED current for a Boost or Buck-boost converter is always less than the average sense resistor current. For the ZXLD1374, ...

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Applications Information (Continued) For example the typical application circuit, in order to get I Setting R = 33kΩ it results GI1 This will result in: Table 1 shows typical resistor values used to determine GI Table 1 GI ...

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Applications Information (Continued) INDUCTOR/FREQUENCY SELECTION     L=22µH L=10µ Figure 32. 1.5A Buck mode inductor selection for target frequency of 400 kHz     ...

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Applications Information (Continued) For example Buck configuration (V 400 kHz, the Ideal inductor size is L= 33µH. The same kind of graphs can be used to select the right inductor for a Buck configuration and a LED current ...

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Applications Information (Continued) In the case of the Buck-boost topology, the following graphs guide the designer to select the inductor for a target frequency of 400kHz (figure 36) or higher than 500kHz (figure 37).     ...

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Applications Information (Continued) For example Buck-boost configuration (V is around 400kHz, the Ideal inductor size is L= 33µH. The same size of inductor can be used if the target frequency is higher than 500kHz driving 6LEDs with a ...

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Applications Information (Continued) Suitable coils for use with the ZXLD1374 may be selected from the MSS range manufactured by Coilcraft, or the NPIS range manufactured by NIC components. The following websites may be useful in finding suitable components www.coilcraft.com www.niccomp.com ...

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Applications Information (Continued) Boost and Buck-boost Ceramic capacitors with X7R dielectric are the best choice due to their high ripple current rating, long lifetime, and performance over the voltage and temperature ranges. BOOTSTRAP CIRCUIT In Boost and Buck-boost modes with ...

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Applications Information (Continued) PWM OUTPUT CURRENT CONTROL & DIMMING The ZXLD1374 has a dedicated PWM dimming input that allows a wide dimming frequency range from 100Hz to 1kHz with 1000:1 resolution; however higher dimming frequencies can be used – at ...

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Applications Information (Continued) The PWM pin is designed to be driven by both 3.3V and 5V logic levels. It can be driven also by an open drain/collector transistor. In this case the designer can either use the internal pull-up network ...

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Applications Information (Continued) The device can be put in standby by taking the PWM pin to ground, or pulling voltage below 0.4V with a suitable open collector NPN or open drain NMOS transistor, for a time exceeding ...

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Applications Information (Continued) Over-Temperature Shutdown The ZXLD1374 incorporates an over-temperature shutdown circuit to protect against damage caused by excessive die temperature. A warning signal is generated on the STATUS output when die temperature exceeds 125°C nominal and the output is ...

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Applications Information (Continued 4.5V 3.6V 2.7V 1.8V 0. the event of more than one fault/warning condition occurring, the higher severity condition will take precedence. E.g. ‘Excessive coil current’ and ‘Out of regulation’ occurring together will ...

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Applications Information (Continued) Over-voltage Protection The ZXLD1374 is inherently protected against open-circuit load when used in Buck configuration. However care has to be taken with open-circuit load conditions in Buck-boost or Boost configurations. This is because in these configurations there ...

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Applications Information (Continued) PCB Layout considerations PCB layout is a fundamental activity to get the most of the device in all configurations. In the following section it is possible to find some important insight to design with the ZXLD1374 both ...

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Applications Examples 1.5A Buck LED driver In this application example, ZXLD1374 is connected as a Buck LED driver with schematic and parts list shown below. The LED driver is able to deliver 1.5A of LED current to single or multiple ...

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Applications Examples 350mA Boost LED diver In this application example, ZXLD1374 is connected as a Boost LED driver with schematic and parts list shown below. The LED driver is able to deliver 350mA of LED current into 12 high brightness ...

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Applications Examples 350mA Buck-boost LED driver In this application example, ZXLD1374 is connected as a Buck- boost LED driver with schematic and parts list shown below. The LED driver is able to deliver 350mA of LED current into 4/5 high ...

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Thermal Impedance 4 3.5 3 2.5 2 1.5 1 0.5 0 -40 -25 -10 ZXLD1374 Document number: DS35032 Rev Diodes Incorporated 60V HIGH ACCURACY 1.5A BUCK/BOOST/BUCK-BOOST LED DRIVER CONVERTER WITH AEC-Q100 Ambient ...

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Ordering Information Device Packaging ZXLD1374EST20TC TSSOP-20EP Where YY stands for last 2 digits of year - 10, 11 and WW stands for week number Package Mechanical Data TSSOP-20EP ZXLD1374 Document number: DS35032 Rev Diodes Incorporated 60V HIGH ...

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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 ...