BD9267KUT ROHM [Rohm], BD9267KUT Datasheet - Page 23

• Manufacturer Part Number: BD9267KUT
• Description: White LED Diver for Backlight of Medium/Large-sized LCDs
• Manufacturer: ROHM [Rohm]

BD9267KUT
◆ ◆ ◆ ◆ Normal operating mode, Boot sequence
◆ ◆ ◆ ◆ PWM dimming mode, Boot sequence
www.rohm.com
TSZ22111・15・001
© 2012 ROHM Co., Ltd. All rights reserved.
Power supply：VCC and DVDD are in normal operating range.
Settings of LED driver（Default settings of register）
When you light the LED by general SPI control, please follow the sequence below.
environment for SPI control. After inputting the power supply of VCC and DVDD, by setting the STB to H, it
can be changed to PWM dimming operation mode achieved by duty control immediately. And the operating
conditions are as below
In BD9267KUT, as process mode, there is a test mode for running the LED driver, even there is no
① Input the power supply of VCC, DVDD.
② Launch the STB from L to H.
③ Write the data to the register by SPI control, then set the LED driver.
④ Input the VSYNC, HSYNC signal which is for PWM dimming.
・VCC=9.0V～35V、 DVDD=3.0V～3.6V
・Set all CHs to ON state （LED １CH～16CH）
・Setting voltage for LED current（Voltage of S1～S16 pin） ：0.30V
・Reference voltage of error amplifier：0.60V
・Soft start setting：16 count of VSYNC
①
Figure 20. Starting Sequence for normal operation
②
③
④
23/28
TSZ02201-0F1F0C100050-1-2
By inputting the SPI control signal
before the PWM signal of VSYNC
and HSYNC, LED can be controlled
with register settings.
03.Aug.2012 Rev.001
Datasheet