zxld1374 Diodes, Inc., zxld1374 Datasheet
zxld1374
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zxld1374 Summary of contents
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... HIGH ACCURACY 1.5A BUCK/BOOST/BUCK-BOOST LED DRIVER CONVERTER Description The ZXLD1374 is an LED driver converter IC with integrated 1.5A low side switch to drive high current LEDs multi- topology converter enabling it to efficiently control the current through series connected LEDs. The multi-topology enables it to operate in Buck, Boost and Buck-boost configurations ...
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... Type refers to whether or not pin is an Input, Output, Input/Output or Power supply pin ZXLD1374 Document number: DS35032 Rev Product Line of Diodes Incorporated Description < 2.5V) to adjust output current from 10% to 200% of ADJ , or auxiliary supply from 6V to 15V supply to reduce internal power IN Page www.diodes.com ZXLD1374 . IN . October 2010 © Diodes Incorporated ...
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... GI ADJ and V voltages between 6.3V and 8V, depending upon load and conditions. IN AUX to provide higher efficiency at low the absence of a voltage AUX IN Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 Unit 1.8 A ± 150 °C °C Min ...
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... V = 1.25V ADJ ≤ 5.5V PWM PWM input low Temperature rising. Temperature falling. Measured into ISM pin and V threshold V = 1.25V ADJ Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 Min Typ Max Units V 5.2 5.6 6.3 V 5.5 6 6.5 1 150 300 µA 90 150 µA 0.7 10 µA 1 ...
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... L LX low or high Onset of output current reduction (V falling) TADJ Output current reduced to <10% of set value (V falling) TADJ V = 1.25V TADJ is near the minimum value of 6V. IN >3.5V SHP Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 Min Typ Max Units 0 µA 4.2 4.5 4.8 3.3 3.6 3.9 3.3 3.6 3.9 3.3 3.6 3 ...
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... Figure 4. Boost LED Current, Switching Frequency vs. V ADJ I LED 100 Figure 6. I Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 900 750 600 I LED 450 Switching Frequency 300 T = 25C 12V AUX IN 150 2LEDs µ ...
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... ADJ 100% 90% 80% 70% 60% 50% 40% 30% 20 12V Page www.diodes.com A Product Line of ZXLD1374 110 125 Junction Temperature (°C) Figure 8. V vs. Temperature REF ° 33µH Ω 150m S Buc k Mode 2 LED ...
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... LED Input Voltage (V) 5 LEDs 7 LEDs 9 LEDs Input Voltage (V) Figure 13. Efficiency vs. Input Voltage and Number of LED Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 = 1.5A LED 13 LEDs 15 LEDs LEDs 15 LEDs LEDs 11 LED s 13 LEDs T = 25° ...
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... Figure 14. I vs. Input Voltage and Number of LED LED 9 LED s 7 LED s 5 LED Input Voltage (V) Figure 15. Frequency ZXLD1374 - Buck Mode = LED s 9 LED s 11 LED s 1 LED Input Voltage (V) Figure 16. Efficiency vs. Input Voltage and Number of LED Page www ...
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... Figure 18. Frequency vs. Input Voltage and Number LED 8 LED s 10 LEDs 12 LEDs Input Voltage (V) Figure 19. Efficiency vs. Input Voltage and Number of LED Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 = 325mA – 0.21 LED RATIO ° 33µH Ω 150m S Ω ...
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... Figure 21. Frequency vs. Input Voltage and N umber of LED 5 LED s 13 LEDs 9.5 11 12.5 Input Voltage (V) Figure 22. Efficiency vs. Input Voltage and Number of LED Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 = 0.23 – with bootstrap RATIO 15 LEDs 13 LEDs 7 LEDs 5 LEDs ° 3µH Ω ...
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... LED s 5 LED s 4 LED s 9.5 11.0 12.5 14.0 Input Voltage (V) 7 LED s 6 LED s 5 LED s 9.5 11.0 12.5 14.0 Input Voltage (V) Page www.diodes.com A Product Line of ZXLD1374 = 350mA – 0.23 – with bootstrap RATIO 8 LED s 7 LED s 5 LED s ° 33µH Ω 150m S Ω GI1 Ω ...
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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 modes by suitable configuration of the external components as shown in the schematics shown in the device operation description ...
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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 Rs, connected between the two inputs of a current monitor within the control loop block. ...
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... LED LED S − 225 mV V ADJ ) I V LED REF Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 . VIN ISM REF ADJ GI SGND Figure 30: Buck configuration R S VIN ISM REF ADJ R GI2 GI R GI1 SGND Figure 31: Boost and Buck-boost ...
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... 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, the recommended potential divider ratio is given by possible to use a different combination of GI pin voltages and sense resistor values to set the LED current. ...
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... INDUCTOR/FREQUENCY SELECTION Recommended inductor values for the ZXLD1374 are in the range 22 µH to 100 µH. The chosen coil should have a saturation current higher than the peak sensed current and a continuous current rating above the required mean sensed current by at least 50%. ...
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... Figure 33: 1.5A Buck mode inductor selection for target frequency > 500kHz ZXLD1374 Document number: DS35032 Rev L=33uH Supply Voltage (V) L=33uH L=22uH Supply Voltage (V) Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 L=47uH 50 60 L=47uH 50 60 October 2010 © Diodes Incorporated ...
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... Document number: DS35032 Rev =24V and 6 LEDs), with a load current of 1.5A; if the target frequency is around IN L=68uH L=47uH Supply Voltage (V) L=33uH L=22uH Supply Voltage (V) Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 L=100uH 50 60 L=47uH 50 60 October 2010 © Diodes Incorporated ...
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... L=22uH Figure 37: 350mA Buck-boost mode inductor selection for target frequency > 500kHz ZXLD1374 Document number: DS35032 Rev Diodes Incorporated L=47uH Supply Voltage (V) L=47uH Supply Voltage (V) Page www.diodes.com A Product Line of ZXLD1374 October 2010 © Diodes Incorporated ...
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... Figure 39: 350mA Boost mode inductor selection for target frequency > 500kHz ZXLD1374 Document number: DS35032 Rev Diodes Incorporated =10-18V and 4 LEDs), with a load current of 350mA; if the target frequency IN =12-24V. IN L=47uH Supply Voltage (V) L=47uH Supply Voltage (V) Page www.diodes.com A Product Line of ZXLD1374 October 2010 © Diodes Incorporated ...
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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 www.wuerth-elektronik.de DIODE SELECTION For maximum efficiency and performance, the rectifier (D1) should be a fast low capacitance Schottky diode* with low reverse leakage at the maximum operating voltage and temperature ...
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... Minimum RMS current = I I − CIN RMS LED use D=0.5 as worst case I − CIN RMS = I I − CIN RMS LED Use MAX Page www.diodes.com ZXLD1374 − − − worst case October 2010 © Diodes Incorporated ...
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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 the expense of dimming dynamic range and accuracy. ...
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... While the maximum recommended pulse is for the PWM signal is10ms. Figure 45. PWM Dimming Minimum and Maximum Pulse ZXLD1374 Document number: DS35032 Rev Figure 44. PWM Dimming from MCU Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 October 2010 © Diodes Incorporated ...
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... TH THRESHOLD ZXLD1374 Document number: DS35032 Rev REF. ADJ at which the current must start to decrease = TH1 THRESHOLD Figure 47. Thermal feedback network = 70˚C TH1 = 3.3kΩ at 70˚C Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 October 2010 © Diodes Incorporated ...
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... 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 disabled when die temperature exceeds 150°C nominal. Normal operation resumes when the device cools back down to 125° ...
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... Figure 49. Diagnostic during Start-Up Page www.diodes.com A Product Line of Diodes Incorporated ZXLD1374 Over C urrent 5 160 160 180 180 200 200 October 2010 © Diodes Incorporated ...
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... MOSFET Q2 will start to turn on causing the PWM pin to be brought low. This will disable to LX output until the voltage on the LX falls below Vz. If the fault exists for longer than 20ms then the ZXLD1374 will enter into a shutdown state. Take care of the max voltage drop on the Q2 MOSFET gate. ...
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... 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 in Buck and Buck-boost/Boost configurations. Here are some considerations useful for the PCB layout: ...
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... LED current, Super Barrier Rectifier (SBR) with low forward voltage is used as free wheeling rectifier. With only a few extra components, the ZXLD1374 LED driver is able to deliver LED power of greater than 60W. This is suitable for applications which require high LED power likes high power down lighting, wall washer, automotive LED lighting etc ...
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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 LED with input voltage ranged from 16V to 28V. ...
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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 brightness LED with input voltage ranged from 7V to 20V. In order to increase the ...
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... Packaging ZXLD1374EST20TC TSSOP-20EP Package Mechanical Data TSSOP-20 EP ZXLD1374 Document number: DS35032 Rev Product Line of Diodes Incorporated Part Reel Status Marking Quantity Active ZXLD1374 2500 θ1 Page www.diodes.com ZXLD1374 Tape Width Reel Size 16mm 13” October 2010 © Diodes Incorporated ...
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... Diodes Incorporated products in such safety-critical, life support devices or systems. Copyright © 2010, Diodes Incorporated ZXLD1374 Document number: DS35032 Rev Product Line of Diodes Incorporated IMPORTANT NOTICE LIFE SUPPORT www.diodes.com Page www.diodes.com ZXLD1374 October 2010 © Diodes Incorporated ...