bd8112efv-m ROHM Co. Ltd., bd8112efv-m Datasheet

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... Automotive White LED Driver IC BD8112EFV-M ●Description BD8112EFV white LED driver with the capability of withstanding high input voltage (36V MAX). This driver has 2ch 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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... BD8112EFV-M ●Electrical characteristics (unless otherwise specified, VCC=12V Ta=25℃) 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] OUTL high-side ON resistance OUTL low –side ON resistance [SW Block] SW low -side ON resistance ...

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... BD8112EFV-M ●Electrical characteristic curves (Reference data) (unless otherwise specified, Ta=25℃) 5.5 VCC=12V 5.3 5.1 4.9 4.7 4.5 -40 - EMPERATUR ℃ ] Fig.1 VREG temperature characteristic 55 Vcc= 12V -40 - TEMPERAT URE:Ta [℃ ] Fig.4 ILED temperature characteristic 100 85 70 VCC=30V 100 ...

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... Vin C IN VCC VREG EN SYNC RT CRT RT COMP R PC Ccomp PWM VDAC ISET R ISET ● Pin layout BD8112EFV-M（HTSSOP-B24） COMP COMP VCC VCC SYNC SYNC ...

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... BD8112EFV-M ● 5V voltage reference (VREG) 5V (Typ.) is generated from the VCC input voltage when the enable pin is set high. This voltage is used to power internal 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. The voltage regulation circuitry operates uninterrupted for output voltages higher than 4 ...

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... BD8112EFV-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 ...

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... BD8112EFV-M ・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. UVLO TSD OVP OCP S SCP ...

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... BD8112EFV-M ・LED Short Detection When the LED-pin voltage ≥ 4.5V (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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... BD8112EFV-M ●Protection Sequence VCC ＊1 EN 4.45V VREG UVLO ＊1 VDAC ＊2 SYNC ＊2 PWM SS ILED1 ILED2 ILED1' ILED2' VLED1 1.0Ｖ VLED2 VLED1' VLED2' 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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... BD8112EFV-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[V/µs] < 4. Select coil, schottky diodes, MOSFET and RCS which meet with the ratings 5 ...

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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 BD8112EFV-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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... BD8112EFV-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 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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... BD8112EFV-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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... BD8112EFV-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 ...

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... BD8112EFV-M VCC VCC CPC2 CIN1 CIN2 CPC1 RPC1 CSS EN SW1 SYNC CRT RRT VREG PWM RFL2 RFL1 FAIL1 FAIL2 SW2 VREG LED1 • 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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... BD8112EFV-M ●How to select parts of application serial No. component name CIN1 1 CIN2 2 CIN3 3 CPC1 4 CPC2 5 RPC1 6 CSS 7 RRT 8 CRT 9 RFL1 10 RFL2 11 CCS 12 RCS1 13 RCS2 14 RCS3 15 RCS5 16 CREG 17 CBT COUT1 24 COUT2 25 ROVP1 26 ROVP2 27 RISET 28 CISET 29 RDAC 30 When performing open/short tests of the external components, the open condition may cause permanent damage to the driver and/or the external components ...

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... BD8112EFV-M ●Interfaces● Input/output Equivalent Circuits (terminal name follows pin number) 1. COMP VREG VREG 2K COMP VREG 167 11. LEDEN 3.3V 10K 10K LEDEN 150K 15. VDAC VREG Vcc 500 VDAC 20. SW Vcc SW 23. BOOT VREG BOOT SW ※All values typical. www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. ...

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... BD8112EFV-M ●Notes for use 1 ． Absolute maximum ratings We are careful enough for quality control about this IC. So, there is no problem under normal operation, excluding that it exceeds the absolute maximum ratings. However, this IC might be destroyed when the absolute maximum ratings, such as impressed voltages or the operating temperature range(Topr), is exceeded, and whether the destruction is short circuit mode or open circuit mode cannot be specified ...

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... BD8112EFV-M ●HTSSOP-B24 HTSSOP-B24 <Dimension> 0.325 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 7.8±0.1 (MAX 8.15 include BURR) (5. 1PIN MARK 0.65 +0.05 0.24 -0.04 19/19 Technical Note + 6° 4° −4° +0.05 0.17 -0.03 S 0.08 S 0.08 M (Unit : mm) （Unit:mm) 2009.09 - Rev.B ...