Global Sources
EE Times-India
Stay in touch with EE Times India
 
EE Times-India > Optoelectronics/Displays
 
 
Optoelectronics/Displays  

Supplement the MAX6948 WLED driver with external PWM control

Posted: 01 Jun 2010     Print Version  Bookmark and Share

Keywords:WLED driver  MAX6978 driver  PWM control 

The MAX6948 WLED driver accepts input voltages between +2.7V to +5.5V and boosts the output voltage up to +28V to drive the backlight in cell phones. If the nominal forward voltage of a WLED is 3V, then the MAX6948's 28V-rated high-voltage port can be used to drive 9 WLEDs in series for cell phone LCD screen backlighting. This high-voltage port provides a stable current of up to 30mA. The intensity of these serial backlighting LEDs is controlled through a 10bit, 1,024-step PWM mechanism.

The MAX6948 has five other general-purpose ports that can also drive LEDs directly from the battery or be used as open-drain I/Os. When used as LED drivers, these 8V-rated ports provide a constant current of either 10mA or 30mA (max) with 8bit, 256-step PWM intensity control.

This application note explains how to add external PWM intensity control to supplement a device's internal PWM. The MAX6948 WLED driver serves as the example device. Configuration settings and performance data are shown.

View the PDF document for more information.





Comment on "Supplement the MAX6948 WLED driver w..."
Comments:  
*  You can enter [0] more charecters.
*Verify code:
 
 
Webinars

Seminars

Visit Asia Webinars to learn about the latest in technology and get practical design tips.

 

Go to top             Connect on Facebook      Follow us on Twitter      Follow us on Orkut

 
Back to Top