mini-box M1-ATX User manual

M1-ATX
6-24V Intelligent Automotive ATX Power Supply
Installation Guide
Version 1.4 (firmware v1.4, 06/06/2008)
P/N M1-ATX-02
Before you start…
Please take a moment and read this manual before you install the M1-ATX in your
vehicle. Often times, rushing into installing the unit can result in serious damage
to your M1-ATX board, computer and probably your car’s electrical system.
The M1-ATX board has several wires that need to be installed in various places.
When installing, always double check the polarity of your wires with a voltmeter.
NEVER use the cigarette plug as a power source, often times the contacts are not capable of delivering high current to
your PC.
1.0 Introduction
Thank you for purchasing the M1-ATX power sequencer / vehicle ATX power supply.
The M1-ATX was designed to work with a wide variety of main boards such as the VIA mini-ITX motherboards as well as
low power Pentium-M or Celeron or Atom . Please note that powering full power Pentium 4 or certain AMD systems is
not recommended due to 12V rail power limitations.
1.1 M1-ATX Logic Diagram
GND
+ Switch Logic 6-24V ATX PSU
PC
ATX power
MotherBoard
ON/OFF switch
M1-
A
TX
Battery
Ignition
-
SW
+
J6
LED
J4
J2
8bit MCU
Reverse and
forward protection
Amplifie
r
Enable
J8 Optional On/OFF switch
1.2 M1-ATX Connection diagram
M1-ATX, top view

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Power Input Connectors
J11 Battery + (un-switched battery, positive)
J12 Ignition (switched battery, positive. Can test by connecting it to Battery +)
J13 Battery - (negative)
Controls and Settings
J2 Controls amplifier via remote ON/OFF. Left pin is RMT, Right pin is GND
J6 To motherboard ON/OFF switch
J7 User jumper settings (A,B,C,D)
J8 To external ON/OFF switch (optional, J8 is in parallel with J6)
Power Output Connectors
J3 Optional HDD power (not shown in this picture)
J5 ATX power connector (to motherboard)
J4 To LED (optional)
Jumper attached=ON
A B C D P Off-delay
(All rails ON) Hard-off (5VSB)
OFF OFF OFF OFF P0 Standard PSU mode
ON OFF OFF OFF P1 5s + 1min AutoLatch* 1 min
OFF ON OFF OFF P2 5s+ 1min AutoLatch* 2 hour
ON ON OFF OFF P3 5s+ 1min AutoLatch* NEVER
OFF OFF ON OFF P4 30s + 1min AutoLatch* 2 hour
ON OFF ON OFF P5 30s + 1min AutoLatch* NEVER
OFF ON ON OFF P6 30min NEVER
ON ON ON OFF P7 3 hour NEVER
OFF OFF OFF ON P8 10 min 1 hour
ON OFF OFF ON P9 15 min 2 hours
OFF ON OFF ON P10 1 hour 75min
IMPORTANT: Always use the “Hibernate” feature, never use
“Standby” as it can severely discharge your battery over
extended periods of time.
NEVER use “Hard-off = NEVER” settings unless you
understand the risks of battery depletion. “Hard-off=NEVER
always keeps 5VSB rail ON!
*AutoLatch is active during the fist 60s of PC operation (and
only during the first 60 seconds). For example, If Ignition is
turned ON and then OFF right away, M1-ATX will latch Ignition
in ON position for the next 60 seconds, allowing your operating
system to fully come up. This will prevent disk drive corruption
or systems that remain hung in the ON position. After the first
60 seconds of system operation, the AutoLatch feature will be
removed and system will shut down at as governed by the
“Off-delay” setting.
P0: In this mode, the M1-ATX behaves like a regular ATX power supply. If J6 is connected to the motherboard, M1-
ATX will also send a gratuitous “ON pulse” to the motherboard right after power is first applied.
If IGNITION is connected to the battery, the unit will shut down if battery is < 11.2V. This is to protect the battery
from over- discharging. If Ignition is not hooked up, M1-ATX will operate from as low as 6V. For more information,
please consult the “UPS mode” documentation on the product page.
P1 (recommended): Sends ON pulse to motherboard when ignition is ON for more than 5 seconds, sends OFF
pulse to motherboard 5 seconds after ignition is turned off. Waits another 60 seconds and then shuts down 5VSB to
conserve battery. In this mode, the M1-ATX consumes less than 0.5mA. This is our recommended setting.
1.2 Power challenges in a Vehicle PC
The 5V Standby Problem: One of most difficult tasks of operating a PC in a vehicle is power consumption while the
computer is OFF. Even when your computer is OFF or in Suspend, it will still consume about 50-150mA on the 5VSB rail.
No matter how big your battery is, you will eventually drain it if proper actions are not taken.
The M1-ATX is addressing these issues by cutting off the 5VSB rail after a pre-defined amount of time (see jumper chart,
HARDOFF). When 5VSB is always active (HARDOFF=Never), M1-ATX constantly monitors the battery levels. 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 > 12V.
Engine Cranks, under-voltage and over-voltage situations. Another difficult task is maintaining stable 3.3V, 5V, 12V
and -12V power to your PC. While car batteries are rated at 12V, they actually provide voltages in between 7-16V (engine
cranks) or as high as 80 volts (load dump). Most of the times, your battery will stay at 13.5V (while car is running) but
extra precautions need to take place in order to prevent such situations. M1-ATX can operate as low as 6V and as high
as 28V while providing strict regulation on all rails along 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 J6 to your amplifier remote control pins to activate the ‘anti-thump’ feature.
M1-ATX User Guide Page 2

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2.0 Mode of operation
1) Ignition=OFF. Nothing happens. M1-ATX is waiting for ignition signals.
2) Ignition=ON. M1-ATX waits for few seconds then turns on the 5VSB rail. After another second M1-ATX 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. The Ignition state will be latched for 60 more
seconds so that the motherboard will have a change to come up in a clean manner.
3) Ignition=ON. Your computer will remain ON.
4) Ignition=OFF. M1-ATX waits for “OFFDELAY” in seconds (see jumper chart) 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). After shutdown, 5VSB will still be provided for another “HARDOFF” seconds. In the
event where the shutdown process is longer than “HARDOFF” (Operating System gets frozen, etc), power will
be shut down hard, turning off all power rails. During the HARDOFF procedure, the battery levels will be
constantly monitored to prevent deep discharge situations.
M1-ATX will go to step 1, if ignition is tuned ON again.
M1-ATX User Guide Page 3