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Title: Core module connector part number on reload board? [Print This Page]

Author: bschiett Time: 10/24/2016 18:09
Title: Core module connector part number on reload board?
Hi everybody,
I am working on a carrier board for the firefly rk3288 reload core module, and I would like to know what the exact part number and manufacturer is of the connector used on the reload board?
In the schematic for the core module I can see there are 311 contacts on the PCB. However in the schematic for the reload board I see a connector with 316 contacts. This is very confusing, can you explain what is going on and what the correct connector is to use when designing a board?
Thanks
Bert

Author: isle Time: 10/25/2016 17:12
hi
the actual pin number of the connector is 310.

in the core board ,there is no pin 310, there are pins ..308,309,311.so the total number is 310.
in the carrier board ,the extra 6pins is for:

so the connector get 316 pins

Author: bschiett Time: 10/25/2016 19:24
Last edited by bschiett In 10/25/2016 19:40 Editor

OK, when I look at the datasheet of the connector
https://drive.google.com/drive/u ... gAqAcy0tcUJOWHhpODA

I see 4 groups, E1-E4, containing each 10 pins, and then I see pins 1-125 and pins 133-281. In total 4x10 + 125 + 149 = 314 pins.

When I look at the pinout of the core module (RK3288_Core_DDR3_V00_Pin_Definition.xls) I indeed see 310 pins.

1) Can you confirm you are just re-numbering the pins, continously from the left side of the connector when viewing from the top?

2) When viewing the connector and the core module from the top, when the core module has been inserted in the connector, does the lefmost pin (pin 1 of group E1) correspond with the leftmost pin on the bottom side of the core module?

3) The reason why I am asking is that in the document RK3288_Core_DDR3_V00_Pin_Definition.xls the photo for the bottom side is showing pin 1 on the left hand side, but it should probably show it on the right hand side, correct?

Thanks for your help and clarification.

B

Untitled.jpg (81.76 KB, Down times: 138)

Author: bschiett Time: 10/25/2016 19:34
Also, when counting from the left, is it correct you use the first 18 pins, then skip 4 pins, then continue counting?

In the file Firefly-RK3288_Reload_V10_TOP_Component.pdf I see that the connector part number is AS0B821-S55B-7H

However on the firefly ali express shop, the connector part number is AS0B821-S78B-7H
https://www.aliexpress.com/store ... 08_32730310670.html

Which connector is the correct one to use?

Author: isle Time: 10/26/2016 10:47

bschiett Posted at 10/25/2016 19:24
OK, when I look at the datasheet of the connector
https://drive.google.com/drive/u ... gAqAcy0tcUJO ...

Hi bschiett:
Yes !you are right,thanks to point out our mistake，we will fix it. thanks!

Author: isle Time: 10/26/2016 10:56

bschiett Posted at 10/25/2016 19:34
Also, when counting from the left, is it correct you use the first 18 pins, then skip 4 pins, then c ...

Hi
yes,as you see ,the two connectors can be used compatibly.
and the AS0B821-S78B-7H from our shop is cheaper than AS0B821-S55B-7H

Author: bschiett Time: 12/29/2016 03:26

isle Posted at 10/26/2016 10:47
Hi bschiett:
Yes !you are right,thanks to point out our mistake，we will fix it. thanks!

Can you have a look at the pinout of the connector on the board we designed? We designed a board for firefly reload core module and I am getting a short circuit between +5V and GND, maybe I made a mistake in the numbering of the pins?
I've attached a screenshot of the left, middle and right of the connector pins on our board.
Thanks for your help

problem-left.PNG (51.95 KB, Down times: 139)

problem-right.PNG (66.56 KB, Down times: 139)

problem-middle.PNG (11.28 KB, Down times: 137)

Author: isle Time: 12/29/2016 14:49
hi Bschiett,
we have received your mail ，and our engineer will respond to your question later.

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