[Repair] Help Needed: MSA Evolution 4000

[nidlaX]

Greetings everyone! It seems I've made an unexpected foray into the world of thermal imaging. I have disassembled an MSA Evolution 4000 firefighting TIC, and it seems to be in some trouble.

Symptoms include:
1. Inability to power on when LCD display is connected.
2. Power management board power on if LCD display is disconnected, but nobody at home in the thermal imaging module!
3. Power management board microcontroller (8-bit Atmel AT90) is functional and outputs serial debug data.
4. Thermal imaging module does not appear to attempt a power on sequence at all. That means no debug data from candidate pins, no change in power draw, no FPC actuation.
5. Thermal imaging module's power connector appears to be supplied roughly 4.5 V on one rail and 6.78 V on another.

I'm interesting in working this puzzle to its conclusion, but I'm wondering if there are any schematics, diagrams, or manuals that can help me. For one thing, I'm unfamiliar with the required power supply rails for the thermal imaging module, and I don't have much information on the model. According to spec sheets, it's a "Customized BAE Microbolometer" with 320 x 240 resolution. From what I've seen in this document, a likely candidate is the BAE SCC205.

TIA for any guidance!

[nidlaX]

I believe the module is definitely a variant of the SCC205 / SIM205, possibly with customized firmware. Here's a product sheet I obtained from their old website (Wayback Machine'd).

[Bill W]

MSA 4000 is the BAE core with MSA 'special functions' implemented in software to make it behave better in the fire camera scenario.

A 205 core runs off a single supply 4 - 9V but at up to 8W.  it is quite hungry especially as the peltier gets into control.
There are also 'battery' in and also an aux 5V *out*.
 At a guess, 'external power' is simply 'battery' after a switch circuit.

Most of my (limited) experience was with a similar 200 core but it had a one quirk which might catch you out, no video out unless terminated in 75R.  205 could be similar ?

However not operating the flag is a bad sign  What are the current draws like ?

regards
Bill

[nidlaX]

Most of my (limited) experience was with a similar 200 core but it had a one quirk which might catch you out, no video out unless terminated in 75R.  205 could be similar ?

However not operating the flag is a bad sign  What are the current draws like ?

Hi Bill, I can see no difference in current draw measured at my power supply when I connect / disconnect the camera module from the power management board. The 75 ohm termination quirk is odd, I'll keep that in mind.

I will have another go at this tomorrow or next week when I start disassembling the core into boards. I'll post lost of teardown pictures as well.

[Bill W]

The boards are a pair so I doubt you'd get anything from the processing board without the power board in place.  I do not have the interconnections between them, which is typical of 'core' suppliers.  You get data on what you are allowed to connect to and nothing else.

Raytheon were a bit better as they were Ok with you making your own detector PCB so you only used the one PCB from them (plus detector, chopper, motor.......).

Might have to get out the sample and fire it up for old times' sake then....

regards
Bill

[nidlaX]

Here are some pictures of the power board:



I've probed around with a scope and noticed that the switching drivers start up for about less than 10ms before everything shuts down. Currently trying to understand why this is the case, but I'm not very familiar with SMPS design. I'm starting my diagnostics with the pair of MOSFETs nearest to the positive supply rail input.

[donk2103]

Hi I'm new to this forum and I hope this is ok to ask but I'm also having difficulty with a msa evolution 4000. The problem that I have is the charging cable plug the wires have came off i was wondering if anyone could give me the wire locations it is the updated plug that is a 90 degree green head that plugs into the camera.
Thank You