Firmware uploading and PHY protection for printed boards production

[efk]

Hello,
I am wondering about 2 points, before making the production of printed boards with MFC52235:

1 - I am looking for an easy way to upload the software into the processor flash ram.
Actually i know only the "USB Coldfire Multilink" solution ; it works well but the connector is a bit big and not easy to put in rear side of the interface casing. I read about using "EzPort", which uses less pins, so this solution would be nice in order to be able to program the chip without opening the interface casing (i mean the possibility to put the connector in rear side of interface casing). But until now i was not able to find a "ready to use" "EzPort" programmer interface on the market. Does somebody know some ?

2 - Regarding the PHY physical connection, is it standard to connect pins70to74 of the MCF52235 to pins1,2,3,6 of the rj45 Ethernet socket ? Or is it strongly advised to insert some protection component between the processor and the Ethernet socket ? Note: the printed boards will be sold to end users, so they need to resist against bad manipulation, like a basic Ethernet hub does.

Regards.

[macl]

On your second question, yes some external components are needed for impedance matching and isolation.

Here is the schematic for the Demo board which shows the recommended circuit configuration.  It uses a Pulse H2019 transformer.  Some RJ-45 jacks have the transformer built in.

http://www.freescale.com/files/32bit/hardware_tools/schematics/M52233DEMO_SCH.pdf?fpsp=1

[macl]

actually on the demo board the transformer is a H1102.

[mjbcswitzerland]

Hi macl

I think that the question is to do with protection rather than impedance matching. Even with the impedance matching the said pins are connected directly to the transformer.

Is there a recommendation concerning additional protection against ESD or surges etc. ?

Regards

Mark



Message Edited by mjbcswitzerland on 2007-10-03 10:30 PM

[efk]

Thank you for your answers.

I knew only the M52235EVB with the PowerOverEthernet & H2019, which is a bit complex. So i was looking for an easier solution. It looks like the H1102 is a good alternative for me.

Regarding the "firmware uploading", i think i should better make a separate post, considering the PHY protection issue is fixed.

Regards.

[jab]

the schematic of the M52235EVB does look complex (with regards to wiring of the H2019NL). but you can wire the PoE pins to earth just as in the H1102 in the M52233DEMO schematic link posted above. so both chips can do the job...just depending on whether you wire for PoE or just to transmit .