Nokia N81 Service Manual

Figure 68 RM-179 key matrix
Backlight and illumination
Display and menu key illumination
Display
The display has 2x2 LEDs in series included for backlight illumination. They are connected to have 4 LEDs in
series and driven with a constant current source SMPS (N2301). Driving current is 15mA and its PWM dimmed
(EN). In addition a “load-disconnect” circuit (N2302) is implemented. This avoids ringing of the output
capacity C2314. Basic filtering on VLEDOUT is done with L2302, C2305 and C2316.
Menu keys
Three LED chains for S60 Keys, Music Keys and Gaming Keys are derived from VLEDOUT and driven by a constant
current source at 5 mA. Each chain has separate ENABLE signal and dimmed with VLEDOUT. Gaming Key LEDs
have additional ESD protection.
RM-179; RM-223
System Module and User Interface
Page 6 –28 COMPANY CONFIDENTIAL Issue 1
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Nokia N81 Specifications

General

Display diagonal	2.4 \
Display resolution	240 x 320 pixels
Display number of colors	16.78 million colors
Ringer type	Polyphonic
Internal memory	8196 MB
Front camera type	Single camera
Rear camera resolution	1600 x 1200 pixels
Personal info management (PIM)	Alarm clock, Calculator, Calendar, Notes, To-do list
Headphone connectivity	3.5 mm
USB 2.0 ports quantity	1
Text prediction system type	T9
Multimedia Messaging Service (MMS)	Multimedia Messaging Service (MMS) is a standard way to send messages that include multimedia content to and from a mobile phone over a cellular network
Form factor	Slider
Product color	Brown
Gaming time	6 h
Browsing time	5 h
Talk time (2G)	4 h
Talk time (3G)	3 h
Battery capacity	1050 mAh
Standby time (2G)	1020 h
Continuous audio playback time	11.5 h
Continuous video playback time	4.5 h
2G standards	GPRS
Data network	wcdma
Bluetooth version	2.0+EDR
Bluetooth profiles	A2DP, BIP, DUN, FTP, GAP, GOEP, HFP, HSP, OPP, SPP
SIM card capability	Single SIM

Weight and Dimensions

Depth	102 mm
Width	50 mm
Height	17.9 mm
Weight	140 g