Nokia 6020b Service Manual

Issue 1 03/2005

COMPANY CONFIDENTIAL

23

Copyright © 2005 Nokia. All Rights Reserved.

RM-31
7 - System Module

Nokia Customer Care

UEMEK has an integrated Audio power amplifier to generate output for the IHF speaker. Block 
diagram of IHF.

For RM-31, the Integrated Hands Free Speaker is used to generate hands free speech, and 
also polyphonic ringing tones. The speaker capsule is mounted into the A Cover, and spring 
contacts are used to connect the IHF Speaker contacts to the PWB.

The IHF is furthermore used to generate alerting and warning tones.

RM-31 is designed to support a fully differential external audio accessory connection. A head-
set can be directly connected to the PopPort

TM

 system connector. Stereo audio is not support-

ed by RM-31. A stereo headset can be connected to RM-31, since left and right paths are 
connected in parallel at the PopPort

TM

 connector.

The external microphone input is fully differential and lines are connected to the UEMEK mi-
crophone input MIC2P/N. The UEMEK (MICB2) provides bias voltage. Microphone input lines 
are ESD protected.

Headset implementation uses separate microphone and earpiece signals. The accessory is de-
tected by the ACI signal when the plug is inserted.

Phoenix audio test

For troubleshooting see Audio faults in Baseband Troubleshooting Instructions.

■ 

RM-31 includes a VGA camera module. The camera supports a video preview mode, with in-
tegrated colour processing, and high quality still image mode, which utilizes the existing mem-
ory and the processing resources of the phone.