User Guide

Issue 1 12/04 COMPANY CONFIDENTIAL 37

RAE-6/RA-4

6 - Baseband Description and Troubleshooting Nokia Customer Care

• S80L backlight

• Keypad backlight

• TK11851L: white LED driver for backlight

• UEMEK PWM signals Dlight and Klight are to turn on/off white LED circuits

Description of operation

There are 6 white LEDs for illumination built in S80L module. There are two LED chains con-

nected in parallel. Each of these chains consists of three LEDs in series. Common TK11851L

driver is used for S80L display and for CMT display + keypad.