bd6590muv ROHM Co. Ltd., bd6590muv Datasheet

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... BD6590MUV ●Description BD6590MUV is white LED driver IC with PWM step-up DC/DC converter that can boost max 40V and current driver that can drive max 30mA. The wide and precision brightness can be controlled by external PWM pulse. BD6590MUV has very accurate current drivers, and it has few current errors between each strings. ...

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... BD6590MUV ●Electrical characteristic(Unless otherwise specified, VBAT=5V +25℃) Parameter Quiescent current Current consumption [PWMPOW Terminal] Low input voltage range1 High input voltage range1 Pull down resistor1 [PWMDRV Terminal] Low input voltage range2 High input voltage range2 Pull down resistor2 [FSEL Terminal] ...

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... Output short PROTECT UVLO Internal Reset Output Over Voltage PROTECT TSD FAULT DETECTOR Control Soft start PWM COMP Control SENCE + OSC TEST GND Fig.1 BD6590MUV block diagram Adapter Battery 4.5V to 30V 4.5V to 5.5V 10µF 4.7µH 2.2µF/50V FAILFLAG SW SW VBAT BD6590MUV PGND GND GND ISET Fig.2 Application example (10LED × ...

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... BD6590MUV ●Pin Assignment Table PIN No. PIN Name In/Out N.C. 4 PGND 5 FAILFLAG 6 OCPSET 7 VDET 8 TEST 9 RSTB 10 ISET 11 GND 12 N.C. 13 LED1 14 LED2 5 LED3 16 LED4 17 LED5 18 LED6 19 N.C. 20 GND 21 PWMDRV 22 VBAT 23 PWMPOW 24 VBAT VBAT PIN PIN GND A VBAT PIN PIN 5.5V Clump GND ...

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... Functions 1) PWM current mode DC/DC converter While BD6590MUV is power ON, the lowest voltage of LED terms is detected, PWM duty is decided to be 0.7V and output voltage is kept invariably. As for the inputs of the PWM comparator as the feature of the PWM current mode, one is overlapped with error components from the error amplifier, and the other is overlapped with a current sense signal that controls the inductor current into Slope waveform to prevent sub harmonic oscillation ...

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... And the IC changes from activation into non-activation, and current does not flow to the coil (0mA). ・Thermal shut down BD6590MUV has thermal shut down function. The thermal shut down works at 175℃ or higher, and the IC changes from activation into non-activation. ...

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... BD6590MUV ●How to set over voltage limit This section is especially mentioned here because the spec shown electrical characteristic is necessary to explain this section. Over voltage limit LED control voltage LED terminal over voltage protect 1. Calculate the conditions that the total value of LED VF is MAX. ...

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... For example, 34kΩ → 1A, 68kΩ → 2A <The estimate of the current value which need for the normal operation > As over current detector of BD6590MUV is detected the peak current, it have to estimate peak current to flow to the coil by operating condition. In case of, ○ Supply voltage of coil = VIN ○ ...

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... BD6590MUV ・Soft start of over current limit for application When the capacitor of OCPSET is set as figure, over current limit can become setting value slowly. This effect is same as internal soft start. When you want to reduce peak current than internal soft start on start up, this way is effective. ...

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... BD6590MUV ●Operating of the application deficiency 1) When 1 LED or 1string OPEN during the operating The LED string that became OPEN isn't lighting, but other LED strings are lighting. Then LED terminal is 0V, output boosts up to the over voltage protection voltage. When over voltage is detected, the feedback of open string isn’ ...

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... LED current driver (PWMDRV) BD6590MUV can control the IC system by PWMPOW, and IC can power off compulsory by setting 0.9V or below. Also, It powers on PWMPOW is at more than 2.1V. After it’s selected to PWMPOW=H, When it is selected at PWMDRV=H, LED current decided with ISET resistance flow. ...

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... BD6590MUV ●LED current setting range LED current can set up Normal current by resistance value (RISET) connecting to ISET voltage. Setting of each LED current is given as shown below. Normal current = 432/RISET (A) Also, Normal current setting range is 10mA~30mA. LED current becomes a leak current MAX 2µA at OFF setting. ...

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... BD6590MUV ●Output voltage ripple for PWM dimming Conditions: 8serial 6parallel, LED current=20mA/ch, VBAT=5V, Coil Power=7V, Ta=25℃, output capacitor =2.2μF(50V/B3) PWMDRV Output Voltage (AC) Input Current ●LED current rise and fall for PWM dimming Conditions: 8serial 6parallel, LED current=20mA/ch, VBAT=5V, Coil Power=7V, Ta=25℃, output capacitor=2.2μF(50V/B3) ...

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... BD6590MUV ●Main characteristics of efficiency Conditions: 10serial 6parallel, LED current=20mA/ch, output capacitor=2.2μF(50V/B3) 100 95 Ta=-40° Ta=25° Efficiency vs duty (10serial x 6strings) 100.0% 90.0% 80.0% 70.0% 60.0% 50.0% 40.0% 30.0% 20.0% 10.0% 0. PWM Duty[%] Efficiency of current driver PWM www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. ...

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... This value is just examples, please made sure the final judgment is under an enough evaluation. ●The separation of the IC power supply and coil power supply BD6590MUV can work in separating the power source in both IC power supply and coil power supply. With this application, it can obtain that decrease of IC power consumption, and the applied voltage exceeds IC rating 7V. ...

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... BD6590MUV ●PCB Layout In order to make the most of the performance of BD6590MUV, its PCB layout is very important. Characteristics such as efficiency and ripple and the likes change greatly with layout patterns, which please note carefully. PWM f =100Hz~1kHz PWM RESET ROC 68kΩ <Input capacitor CVL1 (10μF) for coil> ...

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... O C 26.7kΩ 56kΩ MΩ Top Layer Mid layer 1 Mid layer 2 Bottom layer Fig. 18 PCB Layout 17/26 Technical Note BD6590MUV 2.2µF/10V ...

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... BD6590MUV ●Selection of external parts Recommended external parts are as shown below. When to use other parts than these, select the following equivalent parts. ▪Coil Value Manufacturer Product number 4.7μH TDK LTF5022T-4R7N2R0-LC 4.7μH TDK VLP6810T-4R7M1R6 10μH TDK VLP6810T-100M1R1 4.7μH TOKO A915AY-4R7M 4.7μH TOKO B1015AS-4R7M ▪ ...

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... BD6590MUV ●Notes for use (1) Absolute Maximum Ratings An excess in the absolute maximum ratings, such as supply voltage, temperature range of operating conditions, etc., can break down devices, thus making impossible to identify breaking mode such as a short circuit or an open circuit. If any special mode exceeding the absolute maximum ratings is assumed, consideration should be given to take physical safety measures including the use of fuses, etc ...

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... F AILFLAG SW SW PWM 10kΩ PWM PWMDRV 10kΩ RESET PWMPOW BD6590MUV RSTB TEST OCPSET 68kΩ PGND GND GND Fig.20 10series×6parallel, LED current16mA, Switching frequency 1250kHz setting example Current driver PWM application www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. ...

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... F AILFLAG SW SW VBAT VBAT 2.2MΩ 10kΩ 10kΩ PWMDRV VDET 10kΩ 69.8kΩ PWMPOW BD6590MUV RSTB LED1 TEST LED2 LED3 LED4 LED5 LED6 OCPSET each16mA PGND GND GND ISET 27kΩ 8series×6parallel, LED current 16mA, ...

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... F AILFLAG SW SW VBAT VBAT 2.2MΩ 10kΩ PWMDRV VDET 10kΩ 69.8kΩ PWMPOW BD6590MUV 10kΩ RSTB LED1 TEST LED2 LED3 LED4 LED5 LED6 OCPSET Each 16mA PGND GND GND ISET 27kΩ 6series×4parallel, LED current 16mA, ...

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... Battery 4.5V to 26.6V 4.5V to 5.5V 10µF 4.7µH 2.2µF/50V FAILFLAG SW SW VBAT VBAT PWMDRV VDET 10kΩ PWM PWMPOW f =100Hz~1kHz PWM BD6590MUV 10kΩ RESET RSTB LED1 TEST LED2 LED3 LED4 LED5 LED6 OCPSET 68kΩ PGND GND GND ISET 21.5kΩ 8series×2parallel, LED current 40.2mA, ...

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... F AILFLAG SW SW VBAT VBAT 1MΩ 10kΩ PWMDRV VDET 10kΩ 26.7kΩ PWMPOW BD6590MUV 10kΩ RSTB LED1 TEST LED2 LED3 LED4 LED5 LED6 OCPSET Each 177.6mA PGND GND GND ISET 14.7kΩ 10series×1parallel, LED current177.6mA, ...

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... Control LED current to charged D/A voltage. Show application example and typ control. Please decide final value after you evaluated application, characteristic PWM PWM Fig.34 BD6590MUV Analog style optical application www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. Coil Power Coil Power Battery or adapter Battery or adapter 4 ...

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... BD6590MUV ● Ordering part number Part No. Part No. VQFN024V4040 4.0±0.1 1PIN MARK S 0.08 S 2.4±0.1 C0 0.75 +0.05 0.25 -0.04 0.5 www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved Package MUV: VQFN024V4040 <Tape and Reel information> Tape Embossed carrier tape Quantity ...

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No copying or reproduction of this document, in part or in whole, is permitted without the consent of ROHM Co.,Ltd. The content specified herein is subject to change for improvement without notice. The content specified herein is for the purpose ...