ZXLD1322DCTC ZETEX [Zetex Semiconductors], ZXLD1322DCTC Datasheet
ZXLD1322DCTC
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ZXLD1322DCTC Summary of contents
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ZXLD1322 Buck/boost mode DC-DC converter for LED driving with 700mA output and current control Description The ZXLD1322 is an inductive converter, with an internal switch, designed for driving single or multiple LEDs in series total of 700mA ...
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Pin connections (top-view) Package 14-Pin DFN with exposed pad 4mm x 3mm 0.50mm pitch 1.5W @T =70°C A Block diagram Issue 1 - January 2008 © Zetex Semiconductors plc 2008 Package view DFN14 Package (bottom view). 45° chamfer denotes Pin ...
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Absolute maximum ratings (Voltages relative to GND unless otherwise stated) Operating temperature (top) Storage temperature (Tst) Junction temperature (Tj) Package power dissipation (Ptot) DFN-14 with exposed pad: 4mmx3mm, 0.5mm Pitch DC-DC converter Supply voltage (VIN) ADJ CFB ISENSE TADJ BIAS ...
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Pin description Name Pin # Description ADJ 1 Adjust input • Leave floating, or connect to VREF to set 100% output current. • Drive with dc voltage. (50mV<VADJ< VREF) to adjust output • Drive with low frequency (200Hz) PWM control ...
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Electrical characteristics (Test conditions: VIN = 4V, T DC-DC converter supply parameters Symbol Parameter V Supply voltage IN V (Start) Supply voltage for start- Under-voltage detection threshold UV- normal operation to start-up mode V Under-voltage detection threshold UV+ ...
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DC-DC convertertoutput parameters Symbol Parameter Toff(100) Discharge pulse width Toff(10) Discharge pulse width f Maximum operating LXmax frequency f Switching frequency in start mode Switching NPN transistor Symbol Parameter I Average continuous switch SW (c) current I Maximum ...
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High-side current monitor Symbol Parameter V Supply voltage M_VIN V Sense voltage MON I_ Input current M_VIN TCO Temperature coefficient (MON) BW Bandwidth Gm Transconductance Iout/ VMON Acc Accuracy Reference current monitor Symbol Parameter V Adjust voltage ADJ TCO Temperature ...
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... This refers to the accuracy of output current regulation under normal operation when the feedback loop incorporating the current monitor is active. The tolerances of external components are not included in this figure. Ordering information Device Reel size (mm) ZXLD1322DCTC 33.02 Issue 1 - January 2008 © Zetex Semiconductors plc 2008 Conditions VIN>3V 3.0V< ...
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Device description The ZXLD1322 is a buck/boost mode inductive DC-DC converter, with an internal switch, designed for driving single or multiple LEDs in series total of 700mA output current. Depending upon supply voltage (V ), LED forward ...
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Low voltage operation (start-up mode) For supply voltages below 2V, the normal control loop will have insufficient headroom to operate reliably. This condition is detected by the 'under-voltage comparator', which compares a fraction of the internal supply voltage (Vcc) against ...
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Application notes Setting peak coil current The peak current in the coil is set by the resistor (R according SWpeak Rsense The minimum peak current will depend on operating mode, coil inductance and supply voltage ...
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PWM control A wider dimming range can be achieved by applying a PWM control signal to the ADJ pin to turn the device on and off, giving an average output current proportional to the duty cycle of the control signal. ...
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Thermal compensation of LED current High-luminance LEDs often need to be supplied with a temperature compensated current in order to maintain stable and reliable operation at high temperatures. This is usually achieved by reducing the LED current proportionally from its ...
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Typical operating conditions Inductive converters can operate in either CONTINUOUS mode, where current always flows in the inductor, but rises during the ON period and falls during the OFF period, or DISCONTINUOUS mode, where the current falls to zero during ...
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LED(s) via the Schottky diode D1. With a buck converter, the LED is in series with the coil coil current can flow until the ...
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Additional notes Note that the ON time is set by the time it takes the coil to reach the peak current. This peak value is reduced by the control loop to give the desired LED power, so the ON time ...
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Package outline - DFN1443 E PIN 1 DOT BY MARKING DIM Inches Min Max A 0.0315 0.0354 A1 0.00 0.002 A3 0.008 REF. b 0.0079 0.0118 D 0.1555 0.1594 Note: Controlling dimensions are in millimeters. Approximate dimensions are provided in ...
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Definitions Product change Zetex Semiconductors reserves the right to alter, without notice, specifications, design, price or conditions of supply of any product or service. Customers are solely responsible for obtaining the latest relevant information before placing orders. Applications disclaimer The ...