Specifications

LittleBoard 550 QuickStart Guide 23
Appendix B I/O Interface Board
The I/O Interface board provides the connections for the keyboard, mouse, four USB, and all the
standard audio input/output connections for the LittleBoard 550. The I/O interface board also provides
the Infrared (IR) transceiver, an auxiliary battery connection, an auxiliary voltage connector, PC speaker,
and the reset switch. If you want more information than is provided here, refer to the I/O Board Design
Library located on the LittleBoard 550 Doc & SW CD-ROM for the schematic, BOM, etc.
LB550QSG_06a
LS1
J9
S1
J8
J10
J12
J11
J14
J13
F1
J1
J15
U1
U2
J7
J6J4J3
J2
J5
J16
Keyboard
(J15)
Line In (J3)
MIC In (J4)
Mono
Out (J5)
Speaker Out (J6)
Head Phone Out (J7)
USB 2 & 3
(USB2 )
Stack
Top
(J13)
USB 0 & 1
(USB0 )
Stack
Top
(J14)
Infrared (IR)
Transceiver (U1)
Auxilary
Voltages
(J11)
Aux Battery (J12)
Reset
Switch
(S1)
Utility 1 (J10)Utility 2 (J8)
Utility 3
(J9)
CD-ROM
In (J2)
Audio In/
Out (J16)
Mouse (J1)
Figure B-1. I/O Interface Board
Table B-1. Utility 1 Interface Pin/Signal Descriptions (J10)
Utility 1- J10
Pin # Signal
To Connector & Pin # Description
1 -12 J11-1 -12 Volts
2 GND1 GND J11-2 & 4 tied to Ground
3 -5V J11-3 -5 Volts
4 GND2 GND Ground
5 LED+ NC Not connected – Power On LED
6 PWR Good NC Not connected – Power Good
7 SPKR+ LS1-1 Speaker + Output
8 GND3 GND Ground
9 RSTSW* S1-1 Reset Switch
10 KBD SW NC Not connected (Keyboard Switch)