Thread: MPJA - MECI ASTEC DC-DC Converter

Has anyone ordered from meci. I order a dc-dc (which im not even sure will be enough power) and I never got a confirmation.

Just woundering if they were like eio.

Thanks

I ordered mine from MPJA a few months back. Actually ordered a few just to have some spares OR in case I need some additional power for later upgrades!

BTW. If anyone knows a way to post a graphic into the BB I can put the info RIGHT HERE for everyone? Let me know...

Is there anyway to boost the amp output in this thing. I cant even get it to power my mobo and HD.

I have one at abay, cause I ordered 2 of them and never used the second one. Im trying to get rid of it cause Im playing on getting one of the more expensive dc-dc's with higher amp output.

If you wanna bid: http://cgi.ebay.com/aw-cgi/eBayISAPI...item=292009550

Pin: Desc:
1 - Batt (To a good ground in the car in our case)
2 + Batt (To +12V from car)
3 + Temp Sense (we dont use)
4 - Temp Sense (we dont use)
5 - Adapt (we dont use)
6 + Adapt (we dont use)

On the output (20 pin dip header):

Pin: Desc:
1 -5V
2 -25V (we dont use)
3,4,5,6 0V (ground,if you want. I would tie to common in car)
7,8 +12V
9 -12V
10,11,12 +5V
13-18 Battery state logic signals (we dont use)
19,20 Output to a low current switch (how I turn the supply on and
off

found this on a wearable computers mailing list archive:


43W Power Conversion Module for Portable Computers

Features
--------

- Designed for laptop computer applications
- High effeciency -- 80% minimum
- Extremely samll size -- 120mm x 45mm x 20mm
- Multimode switching battery charger
- Adaptor input reversed polarity protection
- Output short circuit protection
- Multi-level battery low warning
- Fully regulated +5V and +12V outputs
- Battery full signal
- Remote convertor disable
- Battery-in-use signal
- Power OK signal
- -12V output for RS232
- -26V output for LCD
- -5V output for modem
- Light weight (110gm)

Description
-----------

The AA90304 is designed specifically to handle the power conversion requirements in a portable personal computer.
It consists of a DC-DC convertor section and a battery charger section.

The DC-DC convertor section generates 5 regulated DC outputs, +5V, +12V, -12V, -5V and -26V. The +5V and +12V
outputs have tight line and load regulation specifications so that surge loads on +5V and +12V will not affect one
another, or the backlight that runs on +12V.

An unusually high effeciency of 80% minimizes the generation of heat and conserves batty power, extending battery
life by as much as 15% compared to conventional DC-DC convertors used for portable computers.

The battery charger is a highly effecient and intelligent switchmode charger. When the computer is not running and
the battery is not full, the battery is charged with the full rapid charge current of 1.7A to 2.0A. When the
computer is switched on, in order to minimize the loading of the AC adaptor and the generation of heat inside the
computer, the charging current is reduced to the quick charge level of 0.6A. The charger detects the charging state
of the battery. When the battery is fully charged, a temperature sensor located at the battery pack provides
battery temperature information to the charger. The temperature sensor can be either a temperature sensing EC such
as the LM34 or a temperature actuated switch. The charger will declare battery full wehn battery temperature
reaches 43 deg C according to the LM34 or if the temperature actuated switch flips from short to open.

When the DC-DC convertor is running off battery, two battery low signals are generated depending on the amount of
energy left. Batt L1 indicates that battery is running low and not much more energy is left. Batt L2 indicates that
battery is too low and battery life could be affected if the computer is not shut down immediately. Batt L1 usually
turns on a warning LED and Batt L2 is usually hard wired to the computer to initiate a shutdown sequence,
independent of user control.

A Batt-In-Use signal informs the computer that the AC Adaptor is not plugged in. It can be used to initiate battery
conservation prodecures such as timing out of hard disks when the hard disk has not been accessed for an extended
period of time.

A POK (Power OK) signal ensures the computer will power up reset properly.

A Convertor Disable input allows the computer to shut down itself. When directly connected to the Batt L2 signal,
the convertor will shut itself down when battery voltage falls below a dangerous threshold.

Extensive use of surface mount technology packs a lot of power and features inn an unusually small package of 120mm
L x 45mm W x 20mm H (4.72in L x 1.77in W x 0.79in H).

Electrical Characteristics
--------------------------

(Unless otherwise specified, all parameters are specified at 25 deg C ambient temp)

Power Input:

>From Adaptor - floating 18V +/-0.5V 55W
>From Battery - 11V to 16V 4.1A max at 11V

Convertor Outputs:

+5V 3.5A (4.2A surge)
+12V 1.1A (1.4A surge)
-12V 40mA
-26V 40mA
-5V 40mA

Charger Output:

Output Voltage 11V to 16V
Rapid Charge 1.7A - 2.0A
Quick Charge 0.5A - 0.7A
Trickle Charge 50mA - 150mA

Absolute Maximum Ratings:

Adaptor input voltage 0V to +20V
Battery input voltage 0V to +20V
Opterating heatsink temperature 0 to 85 deg C
Storage temperature -40 to +105 deg C

Input Protection:

Adaptor will shut down before output exceeds 80W
Battery protected by internal fuse in DC-DC convertor

DC-DC Convertor Outputs

Nominal Output Voltage +5V +12V -12V -26V -5V
Minimum load (A) 0.3 0.02 0.02 0 0
Maximum load (A) 3.5 1.1 0.04 0.04 0.04
Surge load (A) - 30 secs 4.2* 1.4* - - -
Initial tolerance (+/-%) 2 2 10 25-30 10
Line/load regulation (+/-%) 2 2 10 25-30 10
Output ripple (mV pk-pk) 50 100 100 100 100

Efficiency at maximum load (including charger output) 80% minimum
Quiescent Current (battery current drain when DC-DC convertor is disabled and Adaptor is not in use) < 100uA

*Surge load can only be drawn from either one of the two outputs: +5V or +12V at any instant.

Note: Battery must be connected all the time.

Logic Level
-----------

1. Batt L1, Batt L2, Batt F, Batt in Use, POK

min max unit
VOH 4 5 V at Io = -10uA
HOL 0 0.5 V at Io = 40uA

2. Power Disable

min max unit
VTH 3.5 5.0 V
VIL 0 1.0 V
IIH 8 10 uA at VI = 4V

Output Signals
--------------

POK - Active high with 100mS to 500mS delay after all rails are in regulation
Batt L1 - Active high when battery is below 11.75V +/- 0.1V
Batt L2 - Active high when battery is below 11.30V +/- 0.1V
Batt-In-Use - Active high when Adaptor input is not more than two diode drops above battery input.
Battery Full - Active low when Adaptor is in use and battery is full. Battery is considered full when a thermal
switch connecting to +TS and -TS opens or the temperature sense inputs +TS and -TS have a voltage of >1.09V,
indicating the temperature of the sonsor (for example, LM34) has exceeded 43 deg C. Charger will switch into
Trickle mode when battery is full. Battery full state will only be reset by removal of Adaptor.

Input and Controls
------------------

Power Disable - Turns off DC-DC convertor when pulled high momentarily. DC-DC convertor will remain off until the
Power Switch is toggled off/on.

+TS, -TS - Two wire battery temperature sense input. A termperature sensing IC such as LM34 or a temperature
actuated switch embedded in the battery pack provides temperature information to these inputs. When the voltage
across these two inputs exceeds 1.09V (due to output of LM234 or the opening of the temperature switch), Battery
Full output is enabled and charge switches into Trickle Charge mode.

SW1, SW2 - To be connected to a low current power switch. This switch breaks off the power for the control circuit
of the DC-DC convertor so that it is effectively turned off. A high current switch for interrupting the input power
for the DC-DC convertor is not necessary.

Connector Pinouts
-----------------

JST 6-Way Connector

Pin Connection
1 -Batt
2 +Batt
3 +Temp Sense
4 -Temp Sense
5 -Adaptor
6 +Adaptor

Molex 20-Pin Dual Row Header (Output Connector)

Pin Connection
1 -5V
2 -26V
3 0V
4 0V
5 0V
6 0V
7 +12V
8 +12V
9 -12V
10 +5V
11 +5V
12 +5V
13 Batt L2
14 Batt L1
15 Batt F
16 POK
17 Batt-In-Use
18 Power Disable
19 SW1
20 SW2

Excellent! Wish I had that a few months ago myself!

pictures of my setup using the power supply can be found <a href="http://voodoo.maxexp.com/mp3car/">here</a>. best picture of the power supply wiring is probably <a href="http://voodoo.maxexp.com/mp3car/MVC-039S.JPG">this one...</a>

little hint: if you want the supply always on, connect pin 20 (sw2) and one of the ground wires together instead of pin 19.

[This message has been edited by xd (edited 04-02-2000).]