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Datasheet 6-Channel White LED Driver for up to 72 LEDs BD6581GU ●General Description ●Key Specification BD6581GU is white LED driver IC with PWM step-up Operating power supply voltage range: 2.7V ~ ...
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Datasheet BD6581GU ●Absolute Maximum Ratings All middle size LCD equipments backlight of Notebook PC, portable DVD player, car navigation systems, etc. Parameter Symbol Ratings Unit Condition TEST, VR...
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Datasheet BD6581GU ●Electrical Characteristic – continued (Unless otherwise specified, VBAT=12V, RSTB=2.5V, Ta = +25 ℃) Limits Parameter Symbol Unit Condition Min. Typ. Max. [Switching Regulator] Quie...
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Datasheet BD6581GU ●Pin Descriptions PIN PIN Terminal equivalent In/Out Function Name Number circuit diagram A1 VDET In Detect input for SBD open and OVP C A2 N.C. - No connect pin F A3 SW Out Switchi...
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Datasheet BD6581GU ●Block Diagram VBAT VR EG 300kΩ IN detector UVLO PW MPOW REG Internal Power sup lly kΩ VDET SBD Open protect FAILSEL +over voltage protect ERRAMP ontrol PW Mcomp SW sense SENSP LED4...
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Datasheet BD6581GU ●Typical Performance Curves Figure 4. Current Consumption vs VBAT Figure 5. Quiescent current vs VBAT Ta [o C] Figure 6. Oscillation frequency vs VBAT Figure 7. UVLO vs Temperature ...
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Datasheet BD6581GU ●Typical Performance Curves - continued 65% ff ic ie nc [％ Duty [%] Figure 8. Efficiency vs PWMPOW-HI Duty Figure 9. Efficiency vs PWMDRV-HI Duty ISETH=24kΩ, PWM=200Hz ISETH=24kΩ, P...
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Datasheet BD6581GU LE ur re nt [m ●Typical Performance Curves - continued 1k Hz 16V 200Hz 12V 6V 10k Hz rr [m Duty [%] Figure 12. LED current vs PWMDRV-HI Duty Figure 13. LED current vs PWMPOW-HI Duty...
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Datasheet BD6581GU ●Typical Performance Curves - continued Figure 16. LED current matching vs PWMDRV-HI Duty Figure 17. LED current matching vs PWMDRV-HI Duty PWM = 200Hz (Expansion) PWM = 200Hz Figur...
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Datasheet BD6581GU rr [m ●Typical Performance Curves - continued Figure 21. VOUT response Figure 20. LED current matching vs Power Control PWM (PWMPOW) PWMPOW-HI Duty (Expansion) PWM = 200Hz temp [℃ F...
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Datasheet BD6581GU ●Typical Performance Curves - continued Figure 24. Line Transient (22V to 10V) Figure 25. VOUT@OVP (LED OPEN) www.rohm.com TSZ02201-0G3G0C400170-1-2 © 2012 ROHM Co., Ltd. All rights...
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Datasheet BD6581GU ●Description of Functions 1) PWM current mode DC/DC converter While BD6581GU is power ON, the lowest voltage of LED1, 2, 3, 4, 5, 6 is detected, PWM duty is decided to be 0.5V and o...
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Datasheet BD6581GU 4) External SBD open detect and over voltage protection BD6581GU has over boost protection by external SBD open and over voltage protection. It detects VDET voltage and is stopped o...
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Datasheet BD6581GU (Example 2) In case of, VIN=12.0V, L=4.7µH, fsw=1MHz, VOUT=39V, IOUT=80m A, Efficiency=85% Ipeak = (12.0V / 4.7µH) x (1 / 1MHz) x (1-(12V / 39V)) =1.77A Iave = (39V x 80m A / 12.0V)...
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Datasheet BD6581GU ●How to Select the Number of LED Lines of the Current Driver When the number of LED lines of the current driver is reduced, the un-select can be set the matter that the unnecessary ...
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Datasheet BD6581GU ●Start to Use PWMPOW Terminal for the PWM Control, PWM Operating After RSTB and PWMDRV is changing L → H, input PWM to PWMPOW terminal. There is no constraint in turn of RSTB and PW...
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Datasheet BD6581GU ●Start to Use PWMDRV Terminal for the PWM Control, PWM Operating After RSTB and PWMPOW is changing L → H, input PWM to PWMDRV terminal. There is no constraint in turn of RSTB and PW...
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Datasheet BD6581GU ●Brightness Control There are two dimming method is available, first method is analog dimming that apply analog voltage to ISET terminal, and second method is PWM control via digita...
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Datasheet BD6581GU ●LED Current Setting Range LED current can set up Normal and Starting setting current. LED current can set up Normal current by resistance value (RISETH) connecting to ISETH voltage...
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Datasheet BD6581GU ●The Coil Selection The DC/DC is designed by more than 4.7µH. When L value sets to a lower value, it is possibility that the specific sub-harmonic oscillation of current mode DC / D...
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Datasheet BD6581GU ●Selection of External Parts Recommended external parts are as shown below. When to use other parts than these, select the following equivalent parts. ・Coil Size DC Value Manufactur...
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Datasheet BD6581GU ●Attention Point of Board Layout In board pattern design, the wiring of power supply line should be low Impedance, and put the bypass capacitor if necessary. Especially the wiring i...
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Datasheet BD6581GU ●Application Example Battery Battery 10μF 4.7μH 10LED x 6parallel 10μF 4.7μH 10LED x 4aprallel RTR020N05 SW RTR020N05 SW FAILSEL FAILSEL VDET VDET SENSP SENSP SENSN SENSN Power Powe...
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Datasheet BD6581GU • LED current setting controlled ISETH resistor. 19.6kΩ: 24.5m A 24kΩ: 20m A 30kΩ: 16m A 33kΩ: 14.5m A • Brightness control Please input PWM pulse from PWMPOW or PWMDRV terminal. Pl...
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Datasheet BD6581GU • LED current setting controlled ISETH resistor. 19.6kΩ: 24.5m A 24kΩ: 20m A 30kΩ: 16m A 33kΩ: 14.5m A • Brightness control • Brightness control Please input PWM pulse from PWMPOW o...
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Datasheet BD6581GU • LED current setting controlled ISETH resistor. 19.6kΩ: 24.5m A 24kΩ: 20m A 30kΩ: 16m A 33kΩ: 14.5m A • Brightness control • Brightness control Please input PWM pulse from PWMPOW o...
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Datasheet BD6581GU • LED current setting controlled ISETH resistor. 19.6kΩ: 24.5m A 24kΩ: 20m A 30kΩ: 16m A 33kΩ: 14.5m A • Brightness control • Brightness control Please input PWM pulse from PWMPOW o...
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Datasheet BD6581GU • LED current setting controlled ISETH resistor. * Please select the capacitor which the little bias fluctuation. • Brightness control Please input PWM pulse from PWMPOW or PWMDRV t...
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Datasheet BD6581GU Control LED current to charged D/A voltage. Show application example and typ control. Please decide final value after you evaluated application, characteristic. Battery 10μF 4.7μH 8...
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Datasheet BD6581GU ●Operational Notes (1) Absolute Maximum Ratings An excess in the absolute maximum ratings, such as supply voltage, temperature range of operating conditions, etc., can break down de...
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Datasheet BD6581GU ●Ordering Information Part Number Package Packaging and forming specification GU: VCSP85H2 E2: Embossed tape and reel ●Marking Diagram VCSP85H2 (TOP VIEW) 1PIN MARK Part Number Mark...
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Datasheet BD6581GU ●Revision History Date Revision Changes 03.Dec.2012 001 New Release www.rohm.com TSZ02201-0G3G0C400170-1-2 © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111･15･001 03.Dec.2012 Rev...
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Datasheet Notice ●General Precaution 1) Before you use our Products, you are requested to carefully read this document and fully understand its contents. ROHM shall not be in any way responsible or li...
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Datasheet ●Precaution for Mounting / Circuit board design 1) When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product performance and r...
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Datasheet ●Other Precaution 1) The information contained in this document is provided on an “as is” basis and ROHM does not warrant that all information contained in this document is accurate and/or e...
