IO pin output current rating on STR730

[javida14]

Posted on November 17, 2006 at 11:21

IO pin output current rating on STR730

[javida14]

Posted on November 04, 2006 at 18:53

I see a conflict in the STR73F pdf document 11651. Table 3, in Output Capability shows almost every pin having a rating of 2 mA. In section 3 ''Electrical parameters'', Table 5, indicates Max IO current rating (for both source and sink) having 10 mA. What is the case?

Thanks

Barry

[kaouther]

Posted on November 16, 2006 at 07:02

Hello,

Table3 & table 5 values are different becasue test condition are different:

The output capability in the table 3 is almost 2mA with exception JTDO pin = 4mA & P6.0= 8mA.

However, the table 5, it lists the absolute maximum rating under the maximum stress condition which could damage the device. Note in this table, the I/O type is not specified.

I suggest you to have a look on table 22 , the� output driving current� for the three different I/O types; standard, Med current (JTDO) and High current (P6.0).

Also Fig13..Fig17, graphs shows the results of the output driving current for the I/O types in different temperature.

Hope this confusion is clear.

Regards.

[javida14]

Posted on November 17, 2006 at 04:35

I came to that conclusion after reading the document over again. I was originally planning on driving 5 ma photo-optical devices directly from the I/O pins. I now changed that by using external shift registers with output latches which will drive the devices.

Question: What is the value of the input weak pull-ups? 100K?

Thanks,

Barry

[kaouther]

Posted on November 17, 2006 at 11:21

For the Input pins; pu/pd are with internal 100kΩ weak pull-up or pull down.

For the Weak pu/pd equivalent resistor, please refer to table21.

Regards.