bd8119fm-m ROHM Co. Ltd., bd8119fm-m Datasheet

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... Regulator Type) BD8119FM-M ●Description BD8119FM white LED driver with the capability of withstanding high input voltage (36V MAX). This driver has 4ch constant-current drivers integrated in 1-chip, which each channel can draw up to 150mA max, so that high brightness LED driving can be realized. ...

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... BD8119FM-M ●Electrical Characteristics (unless otherwise specified, V Parameter Circuit current Standby current [VREG Block (VREG)] Reference voltage [OUTH Block] OUTH high-side ON resistance OUTH low-side ON resistance Over-current protection operating voltage [OUTL Block] OUTH high-side ON resistance OUTH low -side ON resistance [SW Block] SW low -side ON resistance ...

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... BD8119FM-M ●Electrical Characteristics – Continued (unless otherwise specified, VCC=12V Ta=25℃) Parameter [LED Output Block] LED current relative dispersion width LED current absolute dispersion width ISET voltage PWM minimum pulse width PWM maximum duty PWM frequency VDAC gain Open detection voltage LED Short detection Voltage ...

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... BD8119FM-M ●Reference data (unless otherwise specified, Ta=25℃) 5.5 5.3 V =12V CC 5.1 4.9 4.7 4.5 -40 - TEMPERATURE:Ta [ ℃ ] Fig.1 VREG temperature characteristic 12V -40 - TEMPERATURE:Ta [℃] Fig.4 ILED temperature characteristic 100 =30V CC V =12V = 150 275 ...

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... BD8119FM-M ●Block diagram Vin C IN CRT Ccomp ISET ●Pin layout 1 COMP SS 2 VCC SYNC 6 GND 7 PWM 8 FAIL1 9 FAIL2 10 LEDEN1 11 LEDEN2 12 LED1 13 LED2 14 Fig.14 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. VREG UVLO TSD OVP ...

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... BD8119FM-M ●5V voltage reference (VREG) 5V (Typ.) is generated from the V circuitry, as well as the voltage source for device pins that need to be fixed to a logical HIGH. UVLO protection is integrated into the VREG pin. voltages higher than 4.5 V (Typ.), but if output voltage drops to 4.3 V (Typ.) or lower, UVLO engages and turns the IC off. ...

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... BD8119FM-M ●Buck-Boost DC/DC controller ・Number of LEDs in series connection Output voltage of the DCDC converter is controlled such that the forward voltage over each of the LEDs on the output is set to 1.0V (Typ.). DCDC operation is performed only when the LED output is operating. When two or more LED outputs are operating simultaneously, the LED voltage output is held at 1.0V (Typ.) per LED over the column of LEDs with the highest VF value ...

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... BD8119FM-M ・Soft Start Function The soft-start (SS) limits the current and slows the rise-time of the output voltage during the start-up, and hence leads to prevention of the overshoot of the output voltage and the inrush current. ・Self-diagnostic functions The operating status of the built-in protection circuitry is propagated to FAIL1 and FAIL2 pins (open-drain outputs). FAIL1 becomes low when UVLO, TSD, OVP, or SCP protection is engaged, whereas FAIL2 becomes low when open or short LED is detected ...

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... BD8119FM-M ・LED Short Detection When the LED-pin voltage  4.7V (TYP) as well as OVP-pin voltage  1.6V (TYP) simultaneously the internal counter starts operating, and approximately after 100ms (when FOSC = 300kHz) the only detected channel (as LED short) latches off. With the PWM brightness control, the detecting operation is processed only when PWM-pin = High. If the condition of the detection operation is released before 100ms (when FOSC = 300kHz), then the internal counter resets. ※ ...

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... BD8119FM-M ●Protection Sequence VCC ＊1 EN 4.5V VREG UVLO ＊1 VDAC ＊2 SYNC ＊2 PWM SS ILED1 ILED2 ILED3 ILED4 VLED1 VLED2 VLED3 VLED4 VOVP ＊4 FAIL1 FAIL2 ① Case for LED2 in open-mode When VLED2＜0.3V and VOVP＞1.7V simultaneously, then LED2 becomes off and FAIL2 becomes low ② ...

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... BD8119FM-M ●Procedure for external components selection Follow the steps as shown below for selecting the external components 1. Work out IL_MAX from the operating conditions. 2. Select the value of RSC such that IOCP > IL_MAX 3. Select the value of L such that 0.05/µs < VOUT / L < 0.3V/ µs 4 ...

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... VIN is when the minimum, and thus the minimum value should be applied in the equation. ・The L value of 10µF  47µF is recommended. The current-mode type of DC/DC conversion is adopted for BD8119FM-M, which is optimized with the use of the recommended L value in the design stage. This recommendation is based upon the efficiency as well as the stability ...

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... BD8119FM-M 5. Selection of the output capacitor Select the output capacitor Cout based on the requirement of the ripple voltage Vpp. Iout Vout Vpp = × Cout Vout+V IN Choose Cout that allows the Vpp to settle within the requirement. Allow some margin also, such as the tolerance of the external components ...

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... BD8119FM-M 8. Setting of the over-voltage protection We recommend setting the over-voltage protection Vovp 1.2V to 1.5V greater than Vout which is adjusted by the number of LEDs in series connection. Less than 1.2V may cause unexpected detection of the LED open and short during the PWM brightness control. For the Vovp greater than 1.5V, the LED short detection may become invalid ...

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... BD8119FM-M ●Power Dissipation Calculation Power dissipation can be calculated as follows: Pc(N) = ICC*VCC + 2*Ciss*VREG*Fsw*Vcc+[VLED*N+△Vf*(N-1)]*ILED I Maximum circuit current CC V Supply power voltage CC C External FET capacitance iss V SW gate voltage frequency sw V LED control voltage LED N LED parallel numeral ΔV LED V ...

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... BD8119FM-M VCC VCC CIN1 CIN2 CPC1 EN SW1 SYNC CRT RRT VREG PWM RFL2 RFL1 FAIL1 FAIL2 SW2 VREG SW3 LED1 LED2 ● The coupling capacitors CVCC and CREG should be mounted as close as possible to the IC’s pins. ● Large currents may pass through DGND and PGND, so each should have its own low-impedance routing to the system ground. ● ...

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... BD8119FM-M ●Application Board Part List serial No. component name 1 CIN1 2 CIN2 3 CIN3 4 CPC1 5 CPC2 6 RPC1 7 CSS 8 RRT 9 CRT 10 RFL1 11 RFL2 12 CCS 13 RCS1 14 RCS2 15 RCS3 16 RCS5 17 CREG 18 CBT COUT1 25 COUT2 26 ROVP1 27 ROVP2 28 RISET 29 CISET 30 RDAC ・The above values are fixed numbers for confirmed operation with the following conditions five series-connected LEDs, and ILED=50mA. ・ ...

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... BD8119FM-M ●Input/output Equivalent Circuits (terminal name follows pin number) 1. COMP VREG VREG 2K COMP VREG 167 RT 11. LEDEN1, 12. LEDEN2 3.3V 10K 10K LEDEN1 LEDEN2 150K 18. VDAC VREG Vcc 500 VDAC 24. SW Vcc SW 27. BOOT VREG BOOT SW ※ All values typical. www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. ...

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... BD8119FM-M ●Notes for use 1) Absolute maximum ratings Use of the IC in excess of absolute maximum ratings (such as the input voltage or operating temperature range) may result in damage to the IC. Assumptions should not be made regarding the state of the IC (e.g., short mode or open mode) when such damage is suffered. If operational values are expected to exceed the maximum ratings for the device, consider adding protective circuitry (such as fuses) to eliminate the risk of damaging the IC ...

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... BD8119FM-M ●Ordering part number Part No. Part No. HSOP-M28 18.5 ± 0.2 (MAX 18.85 include BURR 1.25 5.15 ± 0.1 0.37 ± 0.1 0.8 0.1 S www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved Package FM: HSOP-M28 <Tape and Reel information> Tape Embossed carrier tape Quantity 1500pcs +6° 4° ...

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