zxld1362 Zetex Semiconductors plc., zxld1362 Datasheet

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... Depending upon supply voltage and external components, this can provide watts of output power. The ZXLD1362 includes the output switch and a high-side output current sensing circuit, which uses an external resistor to set the nominal average output current. ...

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... 1.25V ADJ SENSE IN Measured on ADJ pin with pin floating REF (d) V falling ADJ = Driving the ADJ pin above V ADJ ADJ(nom) REF 2 ZXLD1362 =25°C unless otherwise stated) amb Min. Typ. Max 4.85 4. 1.8 pin 95 100 105 SENSE IN ±10 -0 ...

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... Requires external capacitor 22nF. See graphs for more details ADJ pin floating (0 OUT Driving 3 LEDs LX switch ‘ON’ LX switch ‘OFF’ LX switch 'ON' or ‘OFF’ LXmax 3 ZXLD1362 =25°C unless otherwise stated) Min. Typ. Max. Unit 0.2 0.25 0 REF +100mV 10.4 14.2 ...

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... OUTnom ADJ OUTnom from this pin nom = 0.1/R OUT S = 0.1 with ADJ pin open-circuit) SMIN Reel width (inches ZXLD1362 = V = 1.25V giving nominal ADJ REF ) S < 2.5V) to adjust output current from to define nominal average output IN Quantity Device mark per reel 3,000 1362 www.zetex.com ...

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... Adj 3 50K D1 1.25V Gnd 2 Issue 1 - December 2007 © Zetex Semiconductors plc 2007 Voltage regulator 0. 600KHz 20K 1.35V Figure 1 Block diagram 5 ZXLD1362 SENSE Low voltage detector - + www.zetex.com ...

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... S ) across R . The supply referred voltage V SENSE S pin with respect The average output current I IN according to ZXLD1362 ), forms a self zero and there the comparator output switches ADJ . The current IN , the comparator output switches ADJ switching threshold of SENSE OUTnom www ...

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... Figure 2 Theoretical operating waveforms Issue 1 - December 2007 © Zetex Semiconductors plc 2007 7 ZXLD1362 www.zetex.com ...

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... Actual operating waveforms [V Actual operating waveforms [V Actual operating waveforms [V Issue 1 - December 2007 © Zetex Semiconductors plc 2007 =15V, R =0.1 , L=100µ =30V, R =0.1 , L=100µ =60V, R =0.1 , L=100µ ZXLD1362 www.zetex.com ...

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... Issue 1 - December 2007 © Zetex Semiconductors plc 2007 Intentionally left blank 9 ZXLD1362 www.zetex.com ...

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... Issue 1 - December 2007 ZXLD1362 Output Current L=68µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED ZXLD1362 Output Current L=68µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED ZXLD1362 Efficiency L=68µ ...

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... Issue 1 - December 2007 ZXLD1362 Switching Frequency L=68µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED ZXLD1362 Duty Cycle L=68µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED ...

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... Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED ZXLD1360 Output Current L=100µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED ZXLD1362 Efficiency L=100µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 12 ZXLD1362 LED ...

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... Zetex Semiconductors plc 2007 ZXLD1360 Switching Frequency L=100µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED ZXLD1360 Duty Cycle L=100µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED 13 ZXLD1362 LED 15 LED LED 15 LED www.zetex.com ...

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... Issue 1 - December 2007 ZXLD1362 Output Current L=150µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED ZXLD1360 Output Current L=150µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED ZXLD1362 Efficiency L=150µ ...

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... Zetex Semiconductors plc 2007 ZXLD1360 Switching Frequency L=150µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED ZXLD1360 Duty Cycle L=150µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED 15 ZXLD1362 LED 15 LED LED 15 LED www.zetex.com ...

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... Issue 1 - December 2007 ZXLD1362 Output Current L=220µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED ZXLD1362 Output Current L=220µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED ...

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... Issue 1 - December 2007 ZXLD1362 Switching Frequency L=220µ Supply Voltage (V) 1 LED 3 LED 5 LED 7 LED 9 LED 11 LED ZXLD1362 Duty Cycle L=220µ Supply Voltage (V) 1 LED 3 LED 5 LED ...

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... LED Current vs Vadj 1 ADJ Pin Voltage (V) R=100mΩ R=150mΩ R=330mΩ Supply current Output transistor fully enhanced Supply Voltage (V) Vref Supply Voltage (V) Shutdown current Supply Voltage (V) 18 ZXLD1362 www.zetex.com ...

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... Issue 1 - December 2007 Lx on-resistance vs supply voltage Supply Voltage (V) Vadj vs Temperature 0 50 100 Temperature (C) Lx on-resistance vs die temperature 0 50 100 Die Temperature (C) 19 ZXLD1362 -40C 20C 150C 12V 20V 30V 150 200 7V 9V 12V >20V 150 200 ...

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... ADJ pin is driven from an external voltage. (See S ADJ ZXLD1362 GND ) [for 0.3< V <2.5V] S ADJ = V ADJ OUTdc ±25% for voltages below V 20 ZXLD1362 and is given by: REF ), as shown, to adjust the output current . S . When driving the ADJ pin above REF exceeding 1A maximum. and 14.2k REF www.zetex.com (=1.25V). ±25% for ...

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... See the section on PWM dimming for more details of the various modes of control using high frequency and low frequency PWM signals. Issue 1 - December 2007 © Zetex Semiconductors plc 2007 ZXLD1362 GND ZXLD1362 GND ZXLD1362 GND 21 ZXLD1362 can be applied to the ADJ pin, as PWM www.zetex.com ...

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... Actual operating waveforms [V Soft-start operation. Output current (Ch2) and LX voltage (Ch1) Issue 1 - December 2007 © Zetex Semiconductors plc 2007 Soft Start Time vs Capacitance from ADJ pin to Ground Capacitance (nf) =24V, R =0.1 , L=68µH, 22nF on ADJ ZXLD1362 will increase REF 80 100 120 www.zetex.com ...

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... F ceramic capacitor is also used and positioned as close the V A suitable capacitor would be NACEW100M1006.3x8TR13F. The following web sites are useful when finding alternatives: www.murata.com www.niccomp.com www.kemet.com Issue 1 - December 2007 © Zetex Semiconductors plc 2007 This can be an electrolytic capacitor provide ZXLD1362 voltage the I as possible www.zetex.com ...

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... The chosen coil should have a saturation current higher than the peak output current and a continuous current rating above the required mean output current. Suitable coils for use with the ZXLD1362 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 ...

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... LX output silicon diode is used, care should be taken to ensure that the total voltage appearing on the LX pin including supply ripple, does not exceed the specified maximum value. *A suitable Schottky diode would be 30BQ100PBF (IR). Issue 1 - December 2007 © Zetex Semiconductors plc 2007 25 ZXLD1362 www.zetex.com ...

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... This assumes the device to be mounted on a 25mm with 1oz copper standing in still air. Issue 1 - December 2007 © Zetex Semiconductors plc 2007 LED Cled the drive to the output transistor is turned off ZXLD1362 2 PCB www.zetex.com ...

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... The LEDs are usually mounted remotely from the device so, for this reason, the temperature coefficients of the internal circuits for the ZXLD1362 have been optimized to minimize the change in output current when no compensation is employed. If output current compensation is required possible to use an external temperature sensing network - normally using Negative Temperature Coefficient (NTC) thermistors and/or diodes, mounted very close to the LED(s) ...

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... ADJ pin is recommended to minimize changes in output current under these conditions. Evaluation PCB ZXLD1362 evaluation boards are available on request. These boards contain LEDs to allow quick testing of the 1362 device. Additional terminals allow for interfacing to customers own LED products. ...

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... I 0.1D /R [for D OUTavg PWM S PWM This mode is preferable if optimum LED 'whiteness' is required. It will also provide the widest possible dimming range (approx. 1000:1) and higher efficiency at the expense of greater output ripple. Issue 1 - December 2007 © Zetex Semiconductors plc 2007 >0.001] 29 ZXLD1362 www.zetex.com ...

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... Issue 1 - December 2007 © Zetex Semiconductors plc 2007 Millimeters Max. - 1.00 0.10 0.90 0.45 0.20 2.90 BSC 2.80 BSC 1.60 BSC 0.95 BSC 1.90 BSC 0.50 0.25 BSC 12° 30 ZXLD1362 Inches Min. Max. - 0.0393 0.0003 0.0039 0.0330 0.0354 0.0118 0.0177 0.0047 0.0078 0.114 BSC 0.110 BSC 0.062 BSC 0.0374 BSC 0.0748 BSC 0.0118 ...

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... Issue 1 - December 2007 © Zetex Semiconductors plc 2007 Intentionally left blank 31 ZXLD1362 www.zetex.com ...

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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 32 ZXLD1362 www.zetex.com ...