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RH-37
System Module
Nokia Customer Care
Page 12
 Nokia Corporation
Issue 1 07/04
speed of 1 MHz. The DBUS is controlled by the MCU and operates at a speed of 13 MHz. 
Both processors are located in the UPP.
The UEMEK ASIC handles the analog interface between the Baseband and the RF section
. 
UEMEK provides A/D and D/A conversion of the in-phase and quadrature receive and 
transmit signal paths and also A/D and D/A conversions of received and transmitted 
audio signals to and from the user interface. The UEMEK supplies the analog TXC and 
AFC signals to the RF section according to UPP signal control. There are also separate 
signals for PDM coded audio. Digital speech processing is handled by the DSP inside UPP 
ASIC. 
UEMEK is a dual voltage circuit, the digital parts are running from the baseband supply 
1.8V and the analog parts are running from the analog supply 2.78V. Also VBAT is 
directly used (Vibra, LED-driver, Camera Regulator, FCI).
The Baseband supports both internal and external microphone inputs and speaker out-
puts. Keypad tones, DTMF, and other audio tones are generated and encoded by the UPP 
and transmitted to the UEMEK for decoding. An external vibra alert control signals are 
generated by the UEMEK with separate PWM outputs.
EMC shielding is implemented using a soldered shielding, RF cans and PWB grounding.