zxld1321 Zetex Semiconductors plc., zxld1321 Datasheet
zxld1321
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zxld1321 Summary of contents
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... Issue 1 - January 2008 © Zetex Semiconductors plc 2008 DC-DC The feedback control circuitry inside the ZXLD1321 provides excellent load and current regulation, resulting in very stable LED current over the useful life of the battery and over the full operating temperature range. The LED current can be adjusted from 100% ...
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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 1 2 ZXLD1321 www.zetex.com ...
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... The lower of (+5.0V) or (VIN + 0.3V) -0.3V to The lower of (+5.0V) or (VIN + 0.3V) -0.3V to The lower of (+5.0V) or (VIN + 0.3V) -0.3V to The lower of (+5.0V) or (VIN + 0.3V) -0.3V to +18V -0.3V to +5V ) 18V ) 18V CEO 3A (Pulse width = 300µs. Duty cycle<=2 Nominal value 26.3°C/W 3 ZXLD1321 -40 to 125°C -55 to 150°C -40 to 150°C 1.5W at Tamb = 70°C www.zetex.com ...
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... SENSE switch current (ISW )=V PEAK SENSE ) between M_LOAD and M_VIN to define M nominal average output (LED) current of 0.1/R current above a preset temperature threshold. (see section on temperature control for details) 4 ZXLD1321 /R SENSE to sense emitter current) SENSE M www.zetex.com ...
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... Measured on ISENSE pin. Start-up mode VIN=1.2V Measured into ISENSE with pin at 0V. CFB pin brightness control mode Standby state to normal operation VADJ<500mV 100µA injected into ADJ pin 5 ZXLD1321 = 25°C unless otherwise stated Min Typ Max 2.0 12 1.2 2.4 1.8 2.2 1 480 500 ...
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... I =2A, I =50mA =200mA =2A =10V,f=1MHz =10V IN I =2A to Ic<100µ ZXLD1321 Typ Max Units 1.2 1.7 µ µs 600 KHz 50 KHz Typ Max Units 120 mV 209 ...
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... VMON=100mV VMON=10mV VMON=100mV RM = 0.1Ω VMON = 100mV Conditions VADJ=50mV VADJ=500mV VADJ=50mV VADJ=500mV VADJ=500mV Conditions Onset of output current reduction (VTADJ falling) Output current reduced to <10% of set value (VTADJ falling) 7 ZXLD1321 Min Typ Max Units 100 200 mV 0.08 1 µA 370 ppm/ 150 ...
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... Zetex Semiconductors plc 2008 Conditions VIN>3V 3.0V<VIN<12V, (g) Iout=1A, VADJ=100mV 3.0V<VIN<12V, Iout=1A, VADJ=100mV 350mA<I <1A (LED) 350mA<I )<1A (LED Reel width Quantity (mm) per reel 12 8 ZXLD1321 Min Typ Max Units 100 200 ppm %/A 0.5 %/ Device mark 3,000 1321 ...
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... Device description The ZXLD1321 is a inductive boost DC-DC converter, with an internal switch, designed for driving single or multiple LEDs in series total of 1A output current. Depending upon supply voltage (V ), LED forward voltage drop ( output power. Applications cover V ranging from 1.2V to 12V. IN The device employs a modified Pulse Frequency Modulation (PFM) control scheme, with variable " ...
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... The Thermal Control feature can be disabled by leaving the TADJ pin floating connecting it to VREF. Over-temperature shutdown The ZXLD1321 incorporates an over-temperature shutdown circuit to protect the device against damage caused by excess die temperature, resulting from excessive power dissipation in the switch. The output of the 'Over-temp Shutdown' circuit will go high when the die temperature exceeds 150° ...
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... Zetex Semiconductors plc 2008 ) between the switch emitter and ground SENSE will give an approximately linear variation of output ADJ ). The tolerance of the internal 100k resistor and R M (nom). LED 11 ZXLD1321 ADJ forms the lower part of a ADJ (nom) and LED can be ADJ should be ADJ ...
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... LED LED Where duty cycle PWM frequency of 200Hz, or lower is recommended, to minimize errors due to the rise and fall times of the converter output. Issue 1 - January 2008 © Zetex Semiconductors plc 2008 Fig 1 ZXTN25015DFH Fig ZXLD1321 ADJ ZXLD1321 www.zetex.com ...
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... I The 'Thermal compensation current' generator inside the ZXLD1321 provides the necessary thermal compensation current to meet this requirement, using an NTC thermistor and resistor. (Fig 4) The TADJ pin of the device has a voltage threshold of 75mV nominal, which is derived from the reference voltage VREF ...
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... The internal power transistor turns on until the coil current builds up to the peak value. At this point the transistor switches off and the coil current continues to flow in the LED(s) via Schottky diode D1. Issue 1 - January 2008 © Zetex Semiconductors plc 2008 14 ZXLD1321 www.zetex.com ...
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... Value Manufacturer LED Driver Schottky diode 10µH 2A 10µH 2A 10µH 2A 10nF 10V 4.7µF 50V 2.2µF 25V 25mΩ 100mΩ 5.1kΩ 10k 15 ZXLD1321 = 10mV gives a LED ADJ Contact Details Zetex www.zetex.com Zetex Coilcraft www.coilcraft.co m NIC www.niccomp Wurth www.wurth.co.uk Generic Murata 1206 www ...
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... The internal power transistor turns on until the coil current builds up to the peak. At this point the transistor switches off and the coil current continues to flow in the LED(s) via Schottky diode D1. Issue 1 - January 2008 © Zetex Semiconductors plc 2008 Diagram B : Bootstrap mode 16 ZXLD1321 www.zetex.com ...
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... Coilcraft 10µH 2A NIC 10µH 2A Wurth 10nF 10V Generic 4.7µF 50V Murata 1206 2.2µF 25V Murata 1206 25mΩ Generic 0805 Generic 0603 100mΩ Generic 0805 5.1kΩ Generic 0603 10k 103kt1608 17 ZXLD1321 Contact Details www.zetex.com www.coilcraft.co m www.niccomp www.wurth.co.uk www.murata.com www.murata.com www.zetex.com ...
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... LED current from 100 for a voltage change of only 25mV, so any noise on the bottom of the thermistor will seriously affect the accuracy of the Thermal Protection circuit. Issue 1 - January 2008 © Zetex Semiconductors plc 2008 = 50mV). The longer OFF time and ADJ resistor R1 will still give an accurate SENSE , which could perhaps SAT 18 ZXLD1321 ADJ www.zetex.com ...
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... Issue 1 - January 2008 © Zetex Semiconductors plc 2008 Millimeters DIM Min Max 0.70 0.80 D2 0.1240 0.00 0.05 e 0.203 REF. E 0.1161 0.20 0.30 E2 0.0650 3.95 4.05 L 0.0138 19 ZXLD1321 PIN #1 IDENTIFICATION CHAMFER 0.300 X 45° Inches Millimeters Min Max Min 0.1279 3.15 0.0197 BSC 0.50 BSC 0.1201 2.95 0.0689 1.65 0.0177 0.35 www.zetex.com Max 3.25 3.05 1.75 0.45 ...
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... Zetex Semiconductors plc 3701-04 Metroplaza Tower 1 Zetex Technology Park, Chadderton Hing Fong Road, Kwai Fong Oldham, OL9 9LL Hong Kong United Kingdom Telephone: (852) 26100 611 Telephone: (44) 161 622 4444 Fax: (852) 24250 494 Fax: (44) 161 622 4446 asia.sales@zetex.com hq@zetex.com 20 ZXLD1321 www.zetex.com ...