User Guide

Figure 109 External earpiece circuitry (Pop-Port connected on the right)

Vibra circuitry

Vibra is used for vibra-alarm function.

The vibra motor is connected to the Retu ASIC VibraP and VibraN Pulse Width Modulated (PWM) outputs.

Figure 110 Vibra circuitry

Pop-port

connector

Pop-Port

connector provides a fully differential 4–wire connection.

The HandsFree (HF) driver in Retu is meant for the headset.

The output is driven in a fully differential mode. In the fully differential mode, the HF pin is the negative output

and the HFCM pin is the positive output. The gain of the handsfree driver in the differential mode is 6 dB.

The earpiece (EARP, EARN) and headset (HF, HFCM) signals are multiplexed so that the outputs cannot be used

simultaneously.

RM-1

Nokia Customer Care System Module

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