Rohm REFLED005-EVK-002 User manual

4ch White LED Driver Built-in Current Driver
Boost DC/DC Converter for Automotive
BD83A24MUF-M Evaluation Board
(REFLED005-EVK-002)

Notice
www.rohm.com HVA01E
© 2018 ROHM Co., Ltd. All rights reserved.
＜High Voltage Safety Precautions＞
◇Read all safety precautions before use
Please note that this document covers only the BD83A24MUF-M evaluation board
(REFLED005-EVK-002) and its functions. For additional information, please refer to the
datasheet.
To ensure safe operation, please carefully read all precautions before
handling the evaluation board
Depending on the configuration of the board and voltages used,
Potentially lethal voltages may be generated.
Therefore, please make sure to read and observe all safety precautions described in
the red box below.
Before Use
[1] Verify that the parts/components are not damaged or missing (i.e. due to the drops).
[2] Check that there are no conductive foreign objects on the board.
[3] Be careful when performing soldering on the module and/or evaluation board to ensure that solder
splash does not occur.
[4] Check that there is no condensation or water droplets on the circuit board.
During Use
[5] Be careful to not allow conductive objects to come into contact with the board.
[6] Brief accidental contact or even bringing your hand close to the board may result in
discharge and lead to severe injury or death.
Therefore, DO NOT touch the board with your bare hands or bring them too close to the board.
In addition, as mentioned above please exercise extreme caution when using conductive tools such as
tweezers and screwdrivers.
[7] If used under conditions beyond its rated voltage, it may cause defects such as short-circuit or,
depending on the circumstances, explosion or other permanent damages.
[8] Be sure to wear insulated gloves when handling is required during operation.
After Use
[9] The ROHM Evaluation Board contains the circuits which store the high voltage. Since it stores the
charges even after the connected power circuits are cut, please discharge the electricity after using it,
and please deal with it after confirming such electric discharge.
[10] Protect against electric shocks by wearing insulated gloves when handling.
This evaluation board is intended for use only in research and development facilities and
should by handled only by qualified personnel familiar with all safety and operating
procedures.
We recommend carrying out operation in a safe environment that includes the use of high
voltage signage at all entrances, safety interlocks, and protective glasses.

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© 2023 ROHM Co., Ltd. 66UG031E Rev.001
Jun.2023
User’s Guide
LED Driver for Automotive Panel Backlight
4ch White LED Driver Built-in Current Driver
Boost DC/DC Converter for Automotive
BD83A24MUF-M Evaluation Board
REFLED005-EVK-002
Introduction
This user’s guide will provide the necessary steps to operate the Evaluation Board of ROHM’s BD83A24MUF-M LED Driver.
This document includes the external parts, operating procedures and application data.
Description
This Evaluation Board was developed for ROHM’s LED Driver BD83A24MUF-M. BD83A24MUF-M is a white LED driver for
LCD backlight. It has 4ch Current Driver for LED Drive, and it is suitable for high illumination LED drive. It is suitable for
middle size LCD panel drive because LED pin maximum voltage is 50 V.
The dimming is controlled by the PWM signal and can be set up to 20,000: 1@100 Hz.
It also supports analog dimming and can accommodate even higher brightness ranges by combining with PWM dimming.
DC/DC converters can be controlled for boost applications, and the input operating voltage range is 4.5 V to 48V.
Application
Automotive backlight application for CID, cluster panel, car navigation, HUD, or car audio system.
Evaluation board operating condition (default setting)
Table 1. Evaluation board operating condition (default setting)
Parameter Min Typ Max Unit
Power supply voltage *1 7 13.5 18 V
LEDs in series 6 - 10 pcs
LEDs in parallel - 4 - ch
Output voltage *2 19 - 36 V
Output current (per channel) - 80 - mA
DC/DC oscillation frequency - 415 *3 - kHz
Over voltage limit - 41.1 - V
Over current limit - 3.6 - A
*1 This indicates the voltage near the VCC pin. Be careful of voltage drop by the impedance of power line.
*2 Output voltage is determined by the Vf value of the connected LED and the numbers of series. Since this evaluation board
has a boost-configuration, output voltage should be higher than input voltage. Also, output voltage should be lower than OVP
voltage.
*3 The default frequency is set to 415kHz so that it is higher than the EMC standard (LW: 150kHz to 300kHz) even if variations
and SSCG functions are considered.

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© 2023 ROHM Co., Ltd.
66UG031E Rev.001
Jun.2023
User’s Guide
REFLED005-EVK-002
Evaluation board
Figure 1. Top view Figure 2. Bottom view
Evaluation board setup
Figure 3. Evaluation board setup
Operating procedure
1. Connect panel or LEDs to evaluation board. (Anode to VOUT-pin. Cathode to LEDx-pin.)
2. Connect power supply to +B-pin and –B-pin of the evaluation board.
3. Connect power supply to EN-pin. It must be less than 7V.
4. Connect pulse generator to PWM-pin. It should be 100Hz to 25kHz and the minimum pulse width must be
longer than 0.5μs.
5. Turn on the power supply for +B-pin.
6. Turn on the power supply for EN-pin.
7. Turn on the pulse generator for PWM-pin.

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© 2023 ROHM Co., Ltd. 66UG031E Rev.001
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User’s Guide
REFLED005-EVK-002
Operation mode settings
The table below describes the settings for SYNC terminals.
Table 2. Mode settings
Terminal Setting Function
SYNC
GND or OPEN Fixed Frequency Mode Determined by RRT
REG Spread Spectrum Mode (SSCG) of the Frequency
Determined by RRT
Pulse Input Synchronizing to the frequency applied in SYNC pin
For unused channels, pull down the LED pin to GND with 10kΩ.
The ISET terminal voltage can be adjusted according to the voltage
input to the ADIM_P terminal.
The LED current can be calculated from the following equation.
𝐼 = 
 × × 10[mA]
𝑉 = 1.089 [V] (when 90% ≤ DADIM_P ≤ 100%)
𝑉 = 1.089 × 
× 𝐷_ [V] (when 18% < DADIM_P < 90%)
𝐼 is the output current per 1ch (LED current)
(Recommended operating condition:20 mA to 120 mA)
𝑅 is the LED current setting resistor
(Recommended operating condition:11kΩ to 53kΩ)
𝐷_ is the ADIM_P pin input On Duty
(Recommended operating condition:18% to 100%)
Figure 4. Setting LED4 to Unused
Figure 5. ILED vs DADIM_P (RISET = 15.1 kΩ)

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© 2023 ROHM Co., Ltd.
66UG031E Rev.001
Jun.2023
User’s Guide
REFLED005-EVK-002
Pin configuration
Figure 6. Pin configuration
OVP
LGND
LED1 LED2 LED3 LED4
EN REG N.C. VCC CSH GND

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© 2023 ROHM Co., Ltd.
66UG031E Rev.001
Jun.2023
User’s Guide
REFLED005-EVK-002
Evaluation board schematic
Figure 7. Evaluation board schematic

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© 2023 ROHM Co., Ltd.
66UG031E Rev.001
Jun.2023
User’s Guide
REFLED005-EVK-002
Parts list
Table 3. Parts list
No Package Parameters Part name(series) Type Manufacturer
CIN1 - Open - - -
CIN2 3225 10μF, X7S, 50V GCM32EC71H106KA01 3225 Murata
CIN3 1608 0.01μF, R, 50V GCM188R11H103KA01 Ceramic Murata
CIN4 φ8 x L10mm 220μF/35V UCD1V221MNL1GS Electrolytic Nichicon
CIN5 1005 0.1μF, X7S, 50V GCM155R71H104KE37 Ceramic Murata
CIN6 3225 10μF, X7S, 50V GCM32EC71H106KA01 Ceramic Murata
CVCC 2012 1μF, X7S, 50V GCM21BR71H105KA01 Ceramic Murata
CM - - - - -
RCS1 1632 15mΩ LTR18 Resistor Rohm
RCS2 1608 100Ω MCR03 series Resistor Rohm
CCS 1608 100pF GCM1882C1H101JA01 Ceramic Murata
CLDSW 1608 100pF GCM1882C1H101JA01 Ceramic Murata
RCOMP1 1608 100Ω MCR03 series Resistor Rohm
CCOMP1 1005 1μF, X7S, 10V GCM155C71A105KE38 Ceramic Murata
CCOMP2 - Open - - -
RRT1 1608 13kΩ, 1/10W MCR03 series Resistor Rohm
RRT2 1608 12kΩ, 1/10W MCR03 series Resistor Rohm
RFAIL 1608 100kΩ, 1/10W MCR03 series Resistor Rohm
CREG 2012 2.2μF, X7R, 16V GCM21BR71C225KA01 Ceramic Murata
L1 W7.0×L7.4×H4.5mm 22μH SPM7054VT-220M Inductor TDK
M1 W3.3×L3.3×H0.8mm -40V/-27A RQ3G270BJ MOSFET Rohm
L2 W6.3×L6.0×H4.5mm 3.3μH CLF6045NIT-3R3N-D Inductor TDK
D1 W4.7×L2.5×H0.95mm 60V/5A RB088LAM-60 SBD Rohm
D2 W3.5×L1.6×H0.8mm 60V/1A RBR1MM60ATF SBD Rohm
COUT1 1005 0.01μF, R, 50V GCM155R11H103KA40 Ceramic Murata
COUT2 1005 0.1μF, X7S, 50V GCM155R71H104KE37 Ceramic Murata
COUT3 3225 10μF, X7S, 50V GCM32EC71H106KA01 Ceramic Murata
COUT4 φ6.3 x L7.7mm 33μF/50V 50HVPF33M Hybrid SunCon
COUT5 1005 0.1μF, X7S, 50V GCM155R71H104KE37 Ceramic Murata
ROVP1 1608 10kΩ, 1/10W MCR03 series Resistor Rohm
ROVP2 - Short - - -
ROVP3 1608 330kΩ, 1/10W MCR03 series Resistor Rohm
COVP - Open - - -
RISET1 1608 15kΩ, 1/10W MCR03 series Resistor Rohm
RISET2 - Short - - -
CPLSET1 - Open - - -
CPLSET2 1005 1500pF, R, 50V GCM155R11H152KA01 Ceramic Murata

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© 2023 ROHM Co., Ltd.
66UG031E Rev.001
Jun.2023
User’s Guide
REFLED005-EVK-002
Parts list - continued
Table 3. Parts list - continued
No Package Parameters Part name(series) Type Manufacturer
JPSNB - Open - - -
CSNB1 - Open - - -
RSNB1 - Open - - -
CSNB2 - Open - - -
RSNB2 - Open - - -
CLED1 1005 470pF, R, 50V GCM155R11H471KA01 Ceramic Murata
CLED2 1005 470pF, R, 50V GCM155R11H471KA01 Ceramic Murata
CLED3 1005 470pF, R, 50V GCM155R11H471KA01 Ceramic Murata
CLED4 1005 470pF, R, 50V GCM155R11H471KA01 Ceramic Murata
REN - Short - - -
RENH - Open - - -
RENL - Open - - -
RSYNC - Open - - -
RSYNCU - Short - - -
RSYNCD - Open - - -
RPWMREG - Open - - -
RPWM - Short - - -
RADIM - Open - - -
RADIM1 - Short - - -
RLED1 - Open - - -
RLED2 - Open - - -
RLED3 - Open - - -
RLED4 - Open - - -
JP1 - Open - - -
JP2 - Open - - -
JP3 - Open - - -
RADIM2 - Short - - -
RADIM3 - Open - - -
RADIM4 - Open - - -
RADIM5 - Open - - -

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© 2023 ROHM Co., Ltd.
66UG031E Rev.001
Jun.2023
User’s Guide
REFLED005-EVK-002
Board layout
Evaluation board PCB information
Material FR-4
Board thickness 1.6mm
Copper thickness 1 oz.
Number of layers 4
Board size 90X60mm
Minimum copper width 0.15mm
Minimum air gap 0.15mm
Minimum hole size 0.3mm
The layout of BD83A24MUF-M is shown below.
(Top view) (Top view)
(Top view)
Figure 8. Top layer layout
(Top view)
Figure 9. 2nd layer layout
(Top view)
Figure 10. 3rd layer layout
(
Top view)
Figure 11. Bottom layer layout
(Top view)