MOBILE COMMUNICATIONS DIVISION
CUSTOMER SERVICES
Version 1.0 22/11/2006
Created by Konrad Szombara
Page 72 of 103
About handset power management, AD6537B is designed to supply all the
required power in the platform. It provides seven regulator outputs, including
VCORE (1.8V), VMEM (2.93V), VEXT (2.93V), VABB (2.45V), VRTC (1.8V),
VCTCXO (2.75V), VSIM (2.85V), and VMIC (2.75V). VCORE and VMEM
supply the power of all digital signals and VABB supplies all the analog power.
VRTC is used to charge the RTC battery for real time clock module, and
VCTCXO is the power source of the system clock. A hardware-reset pin can
reset all the registers and power supply when system is booted-up. The
following is the detailed description:
6.4.2 MICROPHONE
This handset uses SMD type microphone for better mechanical flexibility.
Their noise canceling mechanisms also provide improved speech pick-up,
noise immunity and reduced echo. The GSM standard requires the
transmitter audio frequency response must fit within a mask as shown in
Figure 5.11, there is no need of frequency response modification when using
the SMD microphone.
Figure Handheld GSM Transmit Audio Frequency Response Mask
6.4.3 RECEIVER
The GSM Standard requires that the receiver audio frequency response
must fit within the mask shown below
Figure Handheld GSM Receive Audio Frequency Response
The frequency response of receiver is adjusted by DSP filter to the meet
requirements of a type 3.2L artificial ear.
