ZXLD1370_1103 DIODES [Diodes Incorporated], ZXLD1370_1103 Datasheet
ZXLD1370_1103
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ZXLD1370_1103 Summary of contents
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HIGH ACCURACY BUCK/BOOST/BUCK-BOOST LED DRIVER-CONTROLLER WITH AEC-Q100 Description The ZXLD1370 is an LED driver controller IC for driving external MOSFETs to drive high current LEDs multi-topology controller enabling it to efficiently control the current through series ...
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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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Functional Block Diagram FLAG STATUS TADJ REF ADJ PWM ZXLD1370 Document number: DS32165 Rev VIN S VAUX VIN ISENSE Error report Fast current monitor Error amp Reference Frequency & hysteresis control ...
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Absolute Maximum Ratings Symbol Parameter Input supply voltage relative to GND V IN Auxiliary supply voltage relative to GND V AUX Current monitor input relative to GND V ISM V Current monitor sense voltage (V SENSE Gate driver output voltage ...
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Electrical Characteristics 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 current into V ...
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Electrical Characteristics (Continued) Symbol Parameter Output Parameters FLAG pin low level output voltage V FLAGL FLAG pin open-drain leakage current I FLAGOFF STATUS Flag no-load output voltage V STATUS (Note 9) Output impedance of STATUS output R STATUS Driver output ...
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Typical Characteristics – Buck Mode – R 1.500 1 LED 3 LEDs 1.490 1.480 1.470 1.460 1.450 1.440 1.430 6.5 11 15.5 Figure 1: Load Current vs. Input Voltage & Number of LED 1000 ...
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Typical Characteristics – Buck Mode – 300mΩ 47µ 0.740 0.735 0.730 0.725 0.720 2 LEDs 3 LEDs 0.715 6.5 11 15.5 1000 2 LEDs 3 LEDs 900 T = 25°C 800 A V ...
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Typical Characteristics – Boost mode – I 0.400 0.350 0.300 0.250 0.200 0.150 0.100 0.050 3 LEDs 4 LEDs 0.000 6.5 10 13.5 500 3 LEDs 4 LEDs 450 T = 25°C 400 ...
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Typical Characteristics – Buck-Boost mode – R 0.370 3 LEDs 0.365 0.360 0.355 0.350 0.345 0.340 0.335 0.330 6.5 8 Figure 10: LED Current vs. Input Voltage & Number of LED 800 3 LEDs 700 600 500 400 300 200 ...
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Applications Information The ZXLD1370 is a high accuracy hysteretic inductive buck/boost/buck-boost controller designed to be used with an external NMOS switch 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 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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Application Information (Continued) A basic ZXLD1370 application circuit is shown in Figures 13 and 15. 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 ...
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Applications Information (Continued) When the ADJ pin is directly connected to the REF pin, this becomes: R 225 LED Note that the average LED current ...
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Applications Information (Continued) Setting R = 33kΩ gives GI1 V ADJ = − = Ω 110 This will result in: R 225 ...
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Applications Information (Continued) L=10µ Figure 20. 1.5A Buck mode inductor selection for target frequency > 500kHz For example buck configuration (V 400 kHz, the Ideal inductor size ...
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Applications Information (Continued) Figure 22. 750mA Buck mode inductor selection for target frequency > 500kHz In the case of the Buck-boost topology, the following graphs guide the designer to ...
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Applications Information (Continued) L=22µ Figure 24. 350mA Buck-Boost mode inductor selection for target frequency > 500kHz For example Buck-bust configuration (VIN =10-18V and 4 LEDs), with a ...
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Applications Information (Continued) L=22µ Figure 26. 350mA Buck-Boost mode inductor selection for target frequency > 500kHz Suitable coils for use with the ZXLD1370 may be selected from the MSS ...
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Applications Information (Continued) Boost / Buck-boost mode D = − MOSFET RMS LED − The resistive power dissipation of the MOSFET is − resistive MOSFET RMS Switching power losses Calculating the ...
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Applications Information (Continued) Assuming that cumulatively the rise time and fall time can account for a maximum of 10% of the period, the maximum frequency allowed in this condition is 20* PERIOD This frequency ...
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Applications Information (Continued) 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. The Schottky diode also provides better efficiency than ...
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Applications Information (Continued) INPUT CAPACITOR The input capacitor can be calculated knowing the input voltage ripple ΔV Buck − LED = C IN Δ − Boost ...
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Applications Information (Continued) PWM OUTPUT CURRENT CONTROL & DIMMING The ZXLD1370 has a dedicated PWM dimming input that allows a wide dimming frequency range from 100Hz to 1kHz with up to 1000:1 resolution; however higher dimming frequencies can be used ...
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Applications Information (Continued) Figure 30. PWM dimming from open collector switch LED current can be adjusted digitally, by applying a low frequency PWM logic signal to the PWM pin to turn the controller on and off. This will produce an ...
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Applications Information (Continued) T pin - Thermal control of LED current ADJ The ‘Thermal control’ circuit monitors the voltage on the T below 625mV. An external NTC thermistor and resistor can therefore be connected as shown below to set the ...
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Applications Information (Continued) FLAG/STATUS Outputs The FLAG/STATUS outputs provide a warning of extreme operating or fault conditions. FLAG is an open-drain logic output, which is normally off, but switches low to indicate that a warning, or fault condition exists. STATUS ...
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Applications Information (Continued) Diagnostic signals should be ignored during the device start – up for 100μs. The device start up sequence will be initiated both during the first power on of the device or after the PWM signal is kept ...
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Applications Information (Continued) Over-voltage Protection The ZXLD1370 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 ZXLD1370 both ...
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Applications Information (Continued) Figure 40. Application circuit: 2.8A Buck LED driver Table 3: Bill of Material Ref No. Value U1 60V LED driver Q1 60V MOSFET D1 45V 10A SBR L1 33µH 4.2A C1 100pF 50V C2 1uF 50V X7R ...
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Applications Information (Continued) Example 2: 400mA Boost LED driver In this application example, the ZXLD1370 is connected as a boost LED driver. The schematic and parts list are shown below. The LED driver is able to deliver 400mA of LED ...
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Applications Information (Continued) Typical Performance Efficiency vs Input Voltage 100% 90% 80% 70% 60% 50% 40% 30% 20% 10 Input Voltage Figure 44. Efficiency Example 3: 700mA Buck-Boost LED driver In this application example, ...
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Applications Information (Continued) Table 5: Bill of Material Ref No. Value U1 60V LED driver Q1 60V MOSFET Q2 60V MOSFET D1 100V 5A Schottky Z1 47V 410mW Zener L1 22µH 2.1A C1 100pF 50V C3 C9 4.7µF 50V X7R ...
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Ordering Information Device Packaging ZXLD1370EST16TC TSSOP-16EP Where YY is last two digits of year and WW is two digit week number Package Data TSSOP-16EP ZXLD1370 Document number: DS32165 Rev Product Line of Diodes Incorporated Part 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 ...