Siemens A55 Repair Documentation

V1.20 Page 26 of 48 ICM MP CCQ GRM
A55/C55_Hitachi Company Confidential © Copyright Siemens AG 04/03
5.1.7 Vibration Motor
The vibration motor is mounted in the lower case. The electrical connection to the
PCB is realised with pressure contacts.
6 Power Supply
6.1 Power Supply ASIC
The power supply ASIC will contain the following functions:
• Powerdown-Mode
• Sleep Mode
• Trickle Charge Mode
• Power on Reset
• Digital state machine to control switch on and supervise the µC with a watchdog
• Voltage regulator
• Low power voltage regulator
• Additional output ports
• Voltage supervision
• Temperature supervision with external and internal sensor
• Battery charge control
• I
2C interface
• Audio multiplexer
• Audio amplifier stereo/mono
• 16 bit Sigma/Delta DAC with Clock recovery and I
2S
• Bandgap reference*
INFO:
* Bandgap reference
The p-n junction of a semiconductor has a bandgap-voltage. This bandgap-voltage is
almost independent of changes in the supply voltage and has a very low temperature
gradient. The bandgap-voltage is used as reference for the voltage regulators.

Siemens A55 Specifications

General

Network	GSM 900 / 1800
Status	Discontinued
Weight	84 g (2.96 oz)
SIM	Mini-SIM
Display Type	Monochrome graphic
Call Records	10 dialed, 10 received, 10 missed calls
Loudspeaker	No
3.5mm Jack	No
Messaging	SMS
Java	No
Stand-by	Up to 250 h
Talk time	Up to 5 h
WAP	No
GPRS	No
Clock	Yes
Alarm	Yes
Calculator	Yes
Calendar	Yes
Announced	2003
Alert Types	Vibration; Downloadable monophonic ringtones
Games	Stack Attack
Battery Type	Removable Li-Ion battery
Resolution	101 x 64 pixels