LM36922H: Please recommend LED driver for E-link display backlight.

YY Kim

Part Number: LM36922H

Dear Sir / Madam,

My customer is considering to use LM36922H for E-link backlight. I've posted E-link backlight requirement. Could you please check if LM36922H can meet this requirement?

According to LM36922H datahseet (6.3 Recommended Operating Conditions), LED string cathode connection is 0 ~ 29.5V. Could you please explain what this mean?

As you can see, E-link backlight needs max 37.2V. LM36922H can not used for E-link backlight due to this?

If LM36922H can not used, could you please recommend proper LED driver? I2C should be supported 1.8V.

Thanks,

YY.

over 3 years ago

0 YY Kim over 3 years ago

Intellectual 410 points

And I read '7.4.5.2 Voltage Limitations on LED1, LED2', can't understand what it means.

Please explain with examples and what VLED1/2 is.

Thanks,

YY.

0 YY Kim over 3 years ago in reply to YY Kim

Intellectual 410 points

I found VIL and VIH of I2C/PWM in datasheet, but can't find VOL and VOH.

Could you please also check VOL and VOH.of I2C/PWM? As I mentioned before, 1.8V I/O voltage should be supported.

Thanks,

YY.

0 YY Kim over 3 years ago in reply to YY Kim

Intellectual 410 points

I'm sorry, my mistake.

SDA/SCL are connected to 1.8V pull-up resistor, VOH will be 1.8V. And PWM is input pin. Right?

Please ignore for VOL / VOH.

Thanks,

YY.

0 Yuting Shao over 3 years ago in reply to YY Kim

TI__Genius 13001 points

Hi,

When LED is short, the voltage of LEDx pin is higher than normal situation and this voltage should be lower than 30V. But, for normal operation, the device can support up to 38V output and the voltage of LEDx is low since there is forward voltage of LED. So it's proper for your design.

BR,

Robin

0 YY Kim over 3 years ago in reply to Yuting Shao

Intellectual 410 points

Hi Robin,

Thanks for your help.

Regards,

YY.

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LM36922H: Please recommend LED driver for E-link display backlight.