| ??? 03/11/05 18:20 Read: times |
#89492 - inconvenient pinouts Responding to: ???'s previous message |
Prahlad J. Purohit said:
Most of the IC's have illogical and inconvinient pinouts. For example: We [ designers ] prefer that databus D0-D7 on an IC must be in one row, I mean pins D0 D1 D2 .. D7 must be next to each other in a line But in a lot of cases its not. What makes these manufacturers have these inconvinient of pinouts? Why cannt they make the pinout in a manner that simlifies the PCB layouts. Some thoughts. I think you're living in the past. Yes, a lot of the earlier 74xxx parts (like say 74xx14 inverters) have inconvenient pinouts, probably more to do with gates on the die and such. However -- pretty much all newer chips, even older stuff like 74xxx245 and its x16 and x32 versions, have inputs on one side and outputs on the other, and they're like this to ease layout. Remember also that for many parts you don't have to use gate A1 for address pin 1. You can swap as needed. (This doesn't work for DRAM!) Even more interesting is that some parts are offered with "mirrored pinouts." Consider a common case where you need a lot of memory so you want to stuff parts on the top and the bottom of your board. Use the mirrored pinout version on the bottom and the address and data and control pins all line up with the parts on the top. -a |
| Topic | Author | Date |
| WEOT: Inconvinient Pinouts. | 01/01/70 00:00 | |
| Cranky pin outs | 01/01/70 00:00 | |
| some like the mother, some the daughter | 01/01/70 00:00 | |
| Z80 family | 01/01/70 00:00 | |
| Not necessarily bad... | 01/01/70 00:00 | |
| It will work....... | 01/01/70 00:00 | |
| When and when not? | 01/01/70 00:00 | |
| RAM/EPROM | 01/01/70 00:00 | |
| Many tolerate it, but some not! | 01/01/70 00:00 | |
| inconvenient pinouts | 01/01/70 00:00 | |
| or thread between pins... | 01/01/70 00:00 | |
| Re: Living in past. | 01/01/70 00:00 | |
| the real question | 01/01/70 00:00 | |
| Errr...... probably | 01/01/70 00:00 | |
| Actually... | 01/01/70 00:00 | |
| erk | 01/01/70 00:00 | |
| Do you mean the package? | 01/01/70 00:00 | |
| package | 01/01/70 00:00 | |
| Max 7301 | 01/01/70 00:00 | |
| All in a days work. | 01/01/70 00:00 | |
FPGA pinouts | 01/01/70 00:00 |