Re: Number of Pins

Ed Casas (edc@ece.ubc.ca) Thu, 7 Dec 2000 04:04:22 -0800 

Date: Thu, 7 Dec 2000 04:04:22 -0800
From: Ed Casas <edc@ece.ubc.ca>
Subject: Re: Number of Pins



> In one of the old finals, there is a question on the minimum
> number of pins required for an 8 kB bytewide RAM chip.  Is the
> relationship one pin to one bit?

Only for the data bus.  The number of pins required for the
address bus is log2 of the number of memory locations.  In this
case 13 address bits are required (8k = 2^13).  So the number of
pins required is at least 21.

Additional pins would be required for things power supply and
ground, chip enable and read/write control, but full marks were
awarded as long as you correctly worked out the number of address
and data bus pins required.

-- 
Ed Casas   edc@ece.ubc.ca   http://casas.ece.ubc.ca   +1 604 822-2592