Specifications

Chapter 3 Hardware
54 Reference Manual ReadyBoard 800
Power Interfaces (J1, J2)
The ReadyBoard 800 uses various voltages onboard, but only one voltage is required externally (+5
volts) through the external connector, which uses a 4-pin header with 0.200" (5.08 mm) spacing. The
optional +12V volts is also provided on the input connector as a pass through voltage, but is not used
on the board except for CPU Fan, LVDS power, PCI-104 bus, and optional ISA bus power. All other
onboard voltages, including the CPU core voltages, are derived from the externally supplied +5 volts
DC +/- 5%.
Power In Interface (J2)
Table 3-24 list the pin outs and signals for Power interface connector (J2).
Table 3-24. Power In Interface Pin/Signal Descriptions (J2)
Pin # Signal Description
1 +5V +5.0 volts DC +/- 5%
2 GND Ground
3 GND Ground
4 +12V This pass through +12 voltage is primarily for PCI-104 bus power, CPU fan, and
LCD power (may also be backlight power).
Notes: The shaded area denotes power or ground. The +12V on the Power Interface connector (J2) is
used for the LVDS (LCD panel), PCI-104 Bus, CPU Fan, and optional ISA Bus power, but may also be
supplied externally.
Power-On Interface (J1)
The signals on this connector allow the ATX power supply to be turned off (soft off) from the
ReadyBoard 800 by operating system (OS) control. If you use a non-ATX power supply (lab supply or
AT power supply) you must connect J1 pin-1 to +5V (pin-1 on J2) to enable the ReadyBoard 800 to
completely power on. However, if you use a non-ATX power supply, then you won’t have the soft off
feature for sleep states normally provided by ATX power supplies.
Table 3-25. Power-On Header Pin/Signal Descriptions (J1)
Pin # Signal Description
1 VCC5SBY +5V Standby Voltage – This voltage (+5V, 100 mA minimum) is supplied from
ATX power supply and is required for normal operation and sleep states.
2 GND Ground
3 PS_ON* Power Supply On – This signal is sent to the ATX power supply from the
ReadyBoard 800 to turn On the ATX power supply. This signal can also be
used to turn Off the ATX power supply or go into a suspended or standby state.
Notes: The shaded area denotes power or ground. The signals marked with * = Negative true logic.
NOTE If the +5V suspend voltage is not present on the Power-On header (J1, pin-1)
the ReadyBoard 800 will not completely power on. The board will have
power (+5V) and Power On LED is lit (green), but it will never power up
completely, because it can not start the boot process.