Nokia 7250, 7250i Service Manual
NHL-4J/NHL-4JX
Company confidential
System Module and User Interface
CCS Technical Documentation
Page 2
Nokia Corporation.
Issue 2 06/03
Table of Contents
Page No
Glossary of Terms.......................................................................................................... 3Introduction.................................................................................................................... 6
Electrical Modules .......................................................................................................6Interconnection Diagram .............................................................................................6Temperature Conditions ..............................................................................................7Humidity ......................................................................................................................7
System Module : Baseband............................................................................................ 8
Baseband Module, technical summary ........................................................................8Technical Summary .....................................................................................................9Environmental Specifications ......................................................................................9
Temperature Conditions............................................................................................ 9Humidity and Water Resistance.............................................................................. 10
Baseband Technical Specifications ...........................................................................11
Absolute Maximum Ratings.................................................................................... 11DC Characteristics................................................................................................... 11Power Distribution diagram .................................................................................... 13
Baseband External and Internal Signals and Connections ........................................14
Integrated HF Speaker............................................................................................. 15FM Radio Interface ................................................................................................. 15Internal Speaker....................................................................................................... 16Integrated HF Speaker............................................................................................. 16
External Signals and Connections .............................................................................20
Keyboard (board-to-board) Connector.................................................................... 20LCD Connector (Board to Board)........................................................................... 21DC Connector.......................................................................................................... 22Bottom Connector ................................................................................................... 22SIM connector ......................................................................................................... 23Internal Signals and Connections............................................................................ 23
Baseband Functional Description ................................................................................ 25
Modes of Operation ...................................................................................................25
No Supply................................................................................................................ 25Back-up ................................................................................................................... 25Acting Dead............................................................................................................. 25Active ...................................................................................................................... 25Sleep Mode.............................................................................................................. 26Charging .................................................................................................................. 26Battery ..................................................................................................................... 26
Power Up and Reset ...................................................................................................27
Power Up with PWR key ........................................................................................ 28Power Up when Charger is connected .................................................................... 28Power Up when Battery is connected ..................................................................... 28RTC Alarm Power Up............................................................................................. 29
A/D Channels .............................................................................................................29FM Radio ...................................................................................................................30
IR Module ............................................................................................................... 30SIM Interface........................................................................................................... 30ACI .......................................................................................................................... 31