mini-box M2-ATX User manual

GND
+
Switch Logic
6-30V DC-
DC
ATX PSU
PC
ATX power
MotherBoard
ON/OFF switch
M2-ATX
Battery
Ignition
-
SW
+
J8
LED
J
5
J6
8bit MCU
Amplifier
Enable
J
9
Reverse and
forward protection
Optional On/OFF switch
M2-ATX
6-24V Intelligent Automotive ATX Power Supply
Installation Guide
Version 1.4 (firmware v1.5, 10/15/2009)
P/N M2-ATX-01
Before you start…
Please take a moment and read this manual before you install the M2-ATX in
your
vehicle. Often times, rushing into installing the unit can result in serious damage
to your M2-ATX board, computer and probably your car’s electrical system.
The M2-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.
Avoid using 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 M2-ATX power sequencer / vehicle ATX power
supply.
The M2-ATX was designed to work with a wide variety of main boards such as
the VIA mini-ITX motherboards as well as Pentium-M, Celeron or certain full
power Core Duo systems.
1.1 M2-ATX Logic Diagram

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1.2 M2-ATX Connection diagram
M2-ATX, top view
Power Input Connectors
J1 Battery + (un-switched battery, positive)
J3 Ignition (To start connect to Battery +). Do not use in the standard
PSU mode (mode P0)
J4 Battery - (negative)
Controls and Settings
J6 Controls amplifier via remote ON/OFF. Left pin is RMT, Right pin is
GND
J8 To motherboard ON/OFF switch
J10 User jumper settings (A,B,C,D)
J9 To external ON/OFF switch (optional, J8 is in parallel with J9)
Power Output Connectors
J2 Optional P4-12V power
J7 ATX power connector (to motherboard)
J5 To LED (optional)
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, M2-ATX will latch Ignition in ON position for the next 60 seconds,
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

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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 M2-ATX behaves like a regular ATX power supply. If J6 is
connected to the motherboard, M2-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, M2-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 M2-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 M2-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), M2-ATX constantly monitors the battery levels.
When battery level drops below 11V for more than one minute, M2-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. M2-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 M2-
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.
2.0 Mode of operation
1) Ignition=OFF. Nothing happens. M2-ATX is waiting for ignition signals.
2) Ignition=ON. M2-ATX waits for few seconds then turns on the 5VSB rail. After another
second M2-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

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75
78
81
84
87
90
93
96
99
6 8 10 12 14 16 18
Vin (V)
12V rail E fficiency (%)
Iout = 5A
Iout = 6A
Iout = 8A
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. M2-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.
5) M2-ATX will go to step 1, if ignition is tuned ON again.
3.0 M2-ATX Characteristics
Minimum Input Operating. voltage 6V
Maximum input Operating voltage 24V (clamping will occur at 25-27V)
Deep-Discharge shutdown
threshold
11.2V
Input current limit (fuse protected) 15A (15A mini-blade fuse)
Max Output Power 160 Watts
Operating temperature -40 to +85* degrees Celsius
Storage temperature -55 to +125 degrees Celsius
MTBF 192,000 hrs @ 50C, 96,000 hrs @65C
Efficiency (Input 9-16V) >94%, all rails combined, 50% load.
PCB size 160x45mm
Input connectors Faston 0.25” terminal
Output Connector ATX Power 20 pin (Molex P/N 39-01-
2200
*Units starts failing at ~115 Celsius. Operating at temperatures above 85C / 185F will drastically reduce the MTBF. When
operating at high temperatures or fanless operation, must reduce PSU load by 25%.
Maximum Power Characteristics
Output Rail Current (Max) Current Peak
(<60 seconds)
Regulation
5V 8A 10A 1.5%
3.3V 8A 10A 1.5%
5VSB 1.5A 2A 1.5%
-12V 0.15A 0.2A 5-%
12V 8A* (see below) 10A 2%
Total power = 169.9 Watts
When operating at 24V or extreme temperatures, de-rate by 30-50%, ventilation will be required.

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12V Rail Output Current
Input (V) 12V rail current Input (V) 12V rail current
6V 4A 11V 8A
7V 5A 12V 8A
8V 6A 14V 8.5A
9V 7A 14-18V 9A
10V 8A 20-26V 7A
For low input voltage (6-10V) ventilation might be required for peak load