2.0 Mode Of Operation - mini-box M1-ATX Installation Manual

http://mini-box.com, Cool Embedded PCs
will still consume about 100mA on the 5V rail. All power supplies have 5VSB (5V
standby) mode so that they can issue at least a PSON signal. When the computer is in
the suspend mode, it will consume even more power, because the RAM needs to be
powered at all times. The power consumption in the suspend mode is few watts.
No matter how big your battery is, it will eventually drain your battery in a matter of days.
The M1-ATX is addressing these issues by cutting off the 5VSb rail after a pre-defined
amount of time (see jumper chart). When 5Vsb is always active (HARDOFF=Never), M1-
ATX watches the battery level. When battery level drops below 11V for more than one
minute, M1-ATX will shut down and re-activate only when the input voltage is > 11V.
Engine Cranks, under-voltage and over-voltage situations. Another very difficult task
is maintaining stable 3.3, 5, 12 and -12V power to your PC. While car batteries are rated
at 12V, they actually can provide voltages in between 7V (during engine cranks) or as
high as hundreds of volts (load dump conditions). Most of the times, your battery will stay
at 13.5V (while car is running) or 12V (when car is off), but extra precautions need to take
place in order to prevent under and over-voltage situations. M1-ATX can operate as low
as 5.7V and as high as 26V while providing strict regulation on all rails with input voltage
clamping and reverse protection.
Loud amplifier pops when PC starts. If your PC is connected to your car amplifier, you
will hear a loud pop when the computer is first started. The M1-ATX has an 'anti-thump'
control that will keep your amp OFF while the PC starts. Simply connect J2 to your
amplifier remote control pins to activate the 'anti-thump' feature.

2.0 Mode of operation

The M1-ATX performs several timing routines and takes actions as follows:
(NOTE: When all config jumpers are removed, M1-ATX will be in the "dumb PSU mode",
no ignition timing, no HARDOFF. M1-ATX will send a gratuitous "ON" signal to the M/B
when power is applied for the first time. Do not connect J8/J6 to the M/B on/off switch if
you don't want your PC to be started automatically)
1)
Ignition=OFF. Nothing happens. M1-ATX is waiting for ignition signals.
2)
Ignition=ON. M1-ATX waits for 3 seconds then turns on the 5Vsb rail. After another 1 second the MCU
sends an "ON" signal to the motherboard via the 2 wires connected to the motherboard's ON/OFF pins.
The motherboard will turn ON and your system should start booting.
3)
Ignition=ON during driving: Nothing happens. Your computer will remain ON.
4)
Ignition=OFF. M1-ATX waits for "OFFDELAY" in seconds (see jumper chart on Page 2) and then it turns
the motherboard OFF by sending a signal to the motherboard's ON/OFF switch. Your computer should
turn off gracefully (shutdown procedure). During this time, power will still be available for your PC to
perform shutdown.
5)
Ignition=OFF. 5VSB will still be provided for another "HARDOFF" seconds (see jumper chart on Page2).
In the event where the shutdown process is longer than "HARDOFF", power will be shut down hard,
turning off your computer's power. If ignition is turned on during this step, you computer will start again. If
M1-ATX User Guide Page 3