Ampro Little Board 700, Reference Manual

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Chapter 3 Hardware
58 Reference Manual LittleBoard 700
Power Interface (J10)
The LittleBoard 700 uses five separate voltages on the board, but only one of the voltages is provided
externally (+5 volts) through the external connector, which uses a 7-pin vertical header with 0.100”
spacing. Holes for a right angle mounting header are also available at J10. All the onboard voltages are
derived from the externally su5 volts DC +/- 5%. The onboard voltages provide the CPU core
voltages as well as other voltages used on the board.
Table 3-27 gives the pin outs and signals for Power supply connector (J10).
Table 3-27. Power Interface Pin/Signal Descriptions (J10)
Pin # Signal Description
1 +5V +5.0 volts DC +/- 5%
2 GND Ground
3 GND Ground
4 +12V This +12V is are for BUS power only (optional)
5 +3.3V This +3.3V is for BUS power only (optional)
6 GND Ground
7 +5V +5.0 volts DC +/- 5%
Notes:
The shaded area denotes power or ground. The +3.3V on the Power Interface
connector (J10) are used for the PCI and ISA bus power and must be supplied externally. The -5V and –
12V are supplied from an external power supply through the Utility 1 connector (J16).
Power Monitor
Power supply monitoring is performed by the precision triple supply monitor, LTC 1326, to monitor the
system voltages and provide an external push button reset capability. The LTC 1326 monitors three
separate voltages Vcore, +5V, and +3.3V. If any of these voltages drop below –10% of the nominal
voltage, the POWER GOOD output is driven low causing a system reset.