Rohm BD82A26MUF-M User manual

BD82A26MUF-M Evaluation Board
REFLED003-EVK-003

Notice
www.rohm.com HVA01E
© 2023 ROHM Co., Ltd. All rights reserved.
＜High Voltage Safety Precautions＞
◇Read all safety precautions before use
Please note that this document covers only the BD82A26MUF-M evaluation board
(REFLED003-EVK-003) 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.
66UG041E Rev.001
Sep.1.2023
User’s Guide
LED Driver for Automotive Panel Backlight
6ch White LED Driver Built-in Current Driver
Boost DC/DC Converter for Automotive
BD82A26MUF-M Evaluation Board
REFLED003-EVK-003
Introduction
This user’s guide will provide the necessary steps to operate the Evaluation Board of ROHM’s BD82A26MUF-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 BD82A26MUF-M. BD82A26MUF-M is a white LED driver for LCD
backlight. It has 6 built-in current drivers for LED drive, making it ideal for high brightness LED drive. LED pin max voltage is 50
V, making it suitable for driving large LCD panels. 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 3.0V 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 - 8 pcs
LEDs in parallel - 6 - ch
Output voltage
*2
19 - 26.5 V
Output current (per channel) - 125 - mA
DC/DC oscillation frequency - 300 - kHz
Over voltage limit - 31 - V
Over current limit - 5.4 - 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.

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© 2023 ROHM Co., Ltd. 66UG041E Rev.001
Sep.2023
User’s Guide
REFLED003-EVK-003
Evaluation board
Figure 1. Top view F igure 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. 66UG041E Rev.001
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User’s Guide
REFLED003-EVK-003
20 kΩ
100 kΩ
LED1
LED2
LED3
LED4
LED5
LED6
REG50
Operation mode settings
The table below describes the settings for SYNC, PD, SHT terminals.
Table 2. Mode settings
Terminal Setting Function
SYNC
GND or OPEN Fixed Frequency Mode Determined by RRT
VREG50 Spread Spectrum Mode (SSCG) of the Frequency
Determined by RRT
Pulse Input Mode to Synchronize with the Frequency Input to the
PD GND or OPEN Phase delay function is disabled
VREG50 Phase delay function is enabled
SHT GND (OPEN is not allowed) LED short protection voltage: V
LEDn
> 4.5V(typ)
DC voltage Input LED short protection voltage: V
LEDn
> input voltage x 10
For unused channels, pull up the LED pin (LED1 to LED6) to REG50
with 100kΩ and pull down to GND with 20kΩ.
Pin configuration
Figure 5. Pin configuration
Figure 4. Setting LED6 to Unused

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© 2023 ROHM Co., Ltd. 66UG041E Rev.001
Sep.2023
User’s Guide
REFLED003-EVK-003
Evaluation board schematic
Figure 6. Evaluation board schemati
Figure 6. Evaluation board schematic

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© 2023 ROHM Co., Ltd. 66UG041E Rev.001
Sep.2023
User’s Guide
REFLED003-EVK-003
Parts list
Table 3. Parts list
No Package Parameters Part name(series) Type Manufacturer
CB1 1005 0.1μF, X7R, 50V GCM155R71H104KE02 Ceramic Murata
CB2 3225 10μF, X7S, 50V GCM32EC71H106KA03 Ceramic Murata
CM1 L12.9 x W6.6 x T9.4mm Open - - -
L1 W7.0 x H4.5 x L7.4mm 4.7μH, 4.1A CLF7045NIT-4R7N-D Inductor TDK
CVCC1 1005 Open - Ceramic -
CVCC2 Φ10 x 10mm 220μF, 50V Nichicon UCD series Electrolytic Nichicon
CVCC3 2012 1μF, X7R, 50V GCM21BR71H105KA03 Ceramic Murata
RCSH 1632 27mΩ, 1.0W LTR18 series Resistor ROHM
M1 HSMT8AG -40V, -27A RQ3G270BJ MOSFET ROHM
CIN1 3225 10μF, X7S, 50V GCM32EC71H106KA03 Ceramic Murata
CIN2 1005 0.1μF, X7R, 50V GCM155R71H104KE02 Ceramic Murata
D1 PMDTM 60V, 5A RB088LAM-60TF SBD ROHM
L2 W10.5 x H6.5 x
L10.0mm 33μH, 8.8A SPM10065VT-330-D Inductor TDK
RG 2012 10Ω, 1/8W MCR10 series Resistor ROHM
M2 HSMT8AG 60V, 12A RQ3L120BKFRA MOSFET ROHM
RCSL 1220 56mΩ, 1.0W LTR10L series Resistor ROHM
RCS 1005 Short - Resistor -
CCS 1005 Open - Ceramic -
D2 PMDTM 60V, 5A RB088LAM-60TF SBD ROHM
COUT1 1005 0.01μF, X7R, 50V GCM155R71H103KA55 Ceramic Murata
COUT2 1005 0.1μF, X7R, 50V GCM155R71H104KE02 Ceramic Murata
COUT3 3225 10μF, X7S, 50V GCM32EC71H106KA03 Ceramic Murata
COUT4 3225 10μF, X7S, 50V GCM32EC71H106KA03 Ceramic Murata
COUT5 Φ8 x 10mm 68μF, 50V GYA1H680MC Hybrid Nichicon
COUT6 1005 Open - Ceramic -
RISET 1005 20kΩ, 1/16W MCR01 series Resistor ROHM
RRT 1005 33kΩ, 1/16W MCR01 series Resistor ROHM
ROVP1 1005 11kΩ, 1/16W MCR01 series Resistor ROHM
ROVP2 1005 330kΩ, 1/16W MCR01 series Resistor ROHM
COVP 1005 Open - Ceramic -
RDIMSEL1 1005 Short - Resistor -
RDIMSEL2 1005 Open - Resistor -
RPLS1 1005 100kΩ, 1/16W MCR01 series Resistor ROHM
RPLS2 1005 100kΩ, 1/16W MCR01 series Resistor ROHM
RPC 1005 200Ω, 1/16W MCR01 series Resistor ROHM
CPC1 1608 1μF, X7R, 16V GCM188R71C105KA49 Ceramic Murata
CPC2 1005 Open - Ceramic -

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User’s Guide
REFLED003-EVK-003
Parts list - continued
Table 3. Parts list - continued
No Package Parameters Part name(series) Type Manufacturer
CREG251 1005 0.22μF, X7R, 16V GCM155R71C224KE02 Ceramic Murata
CREG501 1608 2.2μF, X7S, 10V GCM188C71A225KE01 Ceramic Murata
CREG502 1005 Open - Ceramic -
CP1 3225 10μF, X7S, 50V GCM32EC71H106KA03 Ceramic Murata
CP2 1608 2.2μF, X7S, 10V GCM188C71A225KE01 Ceramic Murata
RFAIL1 1005 100kΩ, 1/16W MCR01 series Resistor ROHM
RFAIL2 1005 100kΩ, 1/16W MCR01 series Resistor ROHM
REN1 1005 Open - Resistor -
REN2 1005 Open - Resistor -
RSYNCU 1005 Short - Resistor -
RSYNCD 1005 Open - Resistor -
RPWM 1005 Open - Resistor -
CSNB1 1005 Open - Ceramic -
CSNB2 1005 Open - Ceramic -
RSNB1 3225 Open - Resistor -
RSNB2 3225 Open - Resistor -
CLED1D 1005 470pF, C0G, 50V GCM1555C1H471JA16 Ceramic Murata
CLED2D 1005 470pF, C0G, 50V GCM1555C1H471JA16 Ceramic Murata
CLED3D 1005 470pF, C0G, 50V GCM1555C1H471JA16 Ceramic Murata
CLED4D 1005 470pF, C0G, 50V GCM1555C1H471JA16 Ceramic Murata
CLED5D 1005 470pF, C0G, 50V GCM1555C1H471JA16 Ceramic Murata
CLED6D 1005 470pF, C0G, 50V GCM1555C1H471JA16 Ceramic Murata
RLED1 1005 Open - Resistor -
RLED2 1005 Open - Resistor -
RLED3 1005 Open - Resistor -
RLED4 1005 Open - Resistor -
RLED5 1005 Open - Resistor -
RLED6 1005 Open - Resistor -
FB1 1005 Short - - -
FB2 1005 Short - - -
FB3 1005 Short - - -
FB4 1005 Short - - -
FB5 1005 Short - - -
FB6 1005 Short - - -

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© 2023 ROHM Co., Ltd. 66UG041E Rev.001
Sep.2023
User’s Guide
REFLED003-EVK-003
Board layout
Evaluation board PCB information
Material FR-4
Board thickness 1.6mm
Copper thickness 1 oz
Number of layers 4
Board size 60X80mm
Minimum copper width 0.15mm
Minimum air gap 0.15mm
Minimum hole size 0.3mm
The layout of REFLED003-EVK-003 is shown below.
(Top view)
Figure 7. Top layer layout
(Top view)
Figure 8. 2nd layer layout
(Top view)
Figure 9. 3rd layer layout
(Top view)
Figure 10. Bottom layer layout
(Top view)

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© 2023 ROHM Co., Ltd. 66UG041E Rev.001
Sep.2023
User’s Guide
REFLED003-EVK-003
Reference application data
(Ta=25°C, Output voltage=25.3V, Iout=125mA x 6ch)
Figure 11. Efficiency vs Input voltage
Figure 12. Gain, Phase vs Frequency (VCC=13.5V)
70
75
80
85
90
95
100
5101520
Efficiency (%)
Input voltage (V)
-180
-120
-60
0
60
120
180
-60
-45
-30
-15
0
15
30
45
60
100 1000 10000 100000 1000000
Phase(deg)
Gain(dB)
Frequency(Hz)
Gail
Phase