LDS8620 IXYS Corporation, LDS8620 Datasheet
LDS8620
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LDS8620 Summary of contents
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... Cell Phones LED Flashlights o LED Flash/Strobe Applications o DESCRIPTION The LDS8620 is a high efficiency multi-mode fractional charge pump with ultra low feedback TYPICAL APPLICATION CIRCUIT © 2009 IXYS Corp. Characteristics subject to change without notice voltage that can drive up to two high-current LEDs. ...
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... LDS8620 ABSOLUTE MAXIMUM RATINGS Parameter Vin, LEDx, C1±, C2± voltage Vout voltage EN/SET voltage Storage Temperature Range Junction Temperature Range Soldering Temperature RECOMMENDED OPERATING CONDITIONS Parameter Vin Ambient Temperature Range I per LED pin LED Total Output Current ( LEDA LEDB Typical application circuit with external components is shown on page 1. ...
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... LDS8620 RECOMMENDED EN/SET TIMING For 2.5 VIN 5.5V, over full ambient temperature range -40 to +85ºC. Symbol Name t EN/SET setup from shutdown SETUP t EN/SET program low time LO t EN/SET program high time HI t EN/SET low time to shutdown OFF t EN/SET Delay to DATA DATADELAY t EN/SET Delay High to ADDRESS RESETDELAY Figure 1 ...
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... LDS8620 Table 3. REG2-4 Current Setting Registers Data Reg2-4 value LED Current, Pulses (binary 000000 1.5 1 111111 96 2 111110 94.5 3 111101 93 4 111100 91.5 5 111011 90 6 111010 88.5 7 111001 87 8 111000 85.5 9 110111 84 10 110110 82.5 11 110101 81 12 110100 79.5 13 110011 78 14 110010 76.5 15 110001 75 16 110000 73.5 17 101111 72 18 101110 70 ...
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... LDS8620 PROGRAMMING EXAMPLES Programming 2 LEDs to 96 mA/output © 2009 IXYS Corp. Characteristics subject to change without notice 5 Doc. No. 8620DS, Rev. N1.1 ...
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... LDS8620 PIN DESCRIPTION Pin # Name connect 2 LEDA LED A cathode terminal 3 LEDB LED B cathode terminal connect 7 V Charge pump output connected to the LED anodes OUT 8 V Charge pump input, connect to battery or supply IN 9 C1+ Bucket capacitor 1 Positive terminal 10 C1- Bucket capacitor 1 Negative terminal ...
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... LDS8620 BLOCK DIAGRAM BASIC OPERATION At power-up, EN/SET pin should be logic LOW. The LDS8620 starts operating in 1-x mode when EN/SET pin is asserted logic high and at least one channel is enabled. At 1-x mode, the approximately equal to the input supply voltage (less any internal voltage losses). If the output voltage is sufficient to regulate all LED currents, the device remains in 1-x operating mode ...
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... V) range, LDS8620 recognizes this OUT condition as “LED Short” and disables this channel with 750 µA control current. If LED pin voltage is less than (Vout – 1.5 V), LDS8620 restores LED current at this particular channel to programmed value Over-Voltage Protection OUT The charge pump’ output voltage V limits at about 6 ...
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... LED with V 3 extend the battery life and achieve highest efficiency. External Components The LDS8620 requires two external 1 µF ceramic capacitors (X5R or X7R type) for decoupling input, output, and two 0.22 µF capacitors (X5R or X7R type) for the charge pump. In all charge pump modes, the input current ripple is very low, and an input bypass capacitor of 1 µ ...
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... LDS8620 PACKAGE DRAWING AND DIMENSIONS 16-PIN TQFN (HV3), 3mm x 3mm, 0.5mm PITCH SYMBOL MIN NOM A 0.70 0.75 A1 0.00 0.02 A2 0.178 0.203 b 0.18 0.23 D 2.90 3.00 D1 1.40 1.55 E 2.90 3.00 E1 1.40 1.55 e 0.50 typ L 0.35 0.40 Note: 1. All dimensions are in millimeters 2. Complies with JEDEC Standard MO-220 © 2009 IXYS Corp. Characteristics subject to change without notice MAX 0 ...
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... All packages are RoHS-compliant (Lead-free, Halogen-free). 2) The standard lead finish is Matte-Tin. 3) The device used in the above example is a LDS8620 002–T2 ( 3x3 TQFN, Tape & Reel). 4) For additional package and temperature options, please contact your nearest IXYS Corp. Sales office. © 2009 IXYS Corp. ...
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... LDS8620 Warranty and Use IXYS CORP. MAKES NO WARRANTY, REPRESENTATION OR GUARANTEE, EXPRESS OR IMPLIED, REGARDING THE SUITABILITY OF ITS PRODUCTS FOR ANY PARTICULAR PURPOSE, NOR THAT THE USE OF ITS PRODUCTS WILL NOT INFRINGE ITS INTELLECTUAL PROPERTY RIGHTS OR THE RIGHTS OF THIRD PARTIES WITH RESPECT TO ANY PARTICULAR USE OR APPLICATION AND SPECIFICALLY DISCLAIMS ANY AND ALL LIABILITY ARISING OUT OF ANY SUCH USE OR APPLICATION, INCLUDING BUT NOT LIMITED TO, CONSEQUENT IAL OR INCIDENTAL DAMAGES ...