Specifications
2 - 5
Table 2-4. Power Connector (J1)
PIN SIGNAL NAME FUNCTION
1 ----- (not used)
2 Ground Ground return
3 Ground Ground return
4 +5VDC +5VDC +/- 5%
Housing: AMP 1-480424-0
Pins: AMP 60619-1
4 3 2 1
J1
Little Board
+5V GND GND
Power Connector
Little Board
GND
GND
+5V
3
4
2
1
Cable Connector Wiring
No Connect
N/C
Figure 2-2. Power Connector Wiring
The precise power requirements of the Little Board/286 depend on a number of factors, including
what functions are present on the board (e.g., expansion DRAM, byte-wide memory devices,
80287/80C87 math coprocessor), whether the SCSI bus is terminated, and what peripherals are
connected to the board's I/O ports. For example, AT keyboards draw their power from the
keyboard connector on the board, and therefore add to the total power drawn by the board from its
power supply. Similarly, boards installed in the onboard expansion module position or
connected to the AT Expansion Bus may draw their power through the Little Board/286.
Assuming a CMOS 80C286 processor is in use, a fully populated Little Board/286 having 1
megabyte of SIMM RAM installed (without the math coprocessor or MiniModules installed)
requires approximately 8 watts of power (1600 mA). Note that the SCSI bus terminators
consume approximately .8 watts of power by themselves, so it is important not to have them
plugged into the board if SCSI is not needed. Operating the CPU with the half-speed option
enabled will also reduce power consumption.