Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : Rambus (RMBS) - Eagle or Penguin -- Ignore unavailable to you. Want to Upgrade?

To: TigerPaw who wrote (33667)	11/3/1999 3:14:00 PM
From: John Walliker	Read Replies (1) \| Respond to of 93625

TigerPaw, As I understood it, The current charges up the line like a capacitor before the signal begins propogating. No, the line looks much more like a resistor. It has uniformly distributed inductance and capacitance (and a small amount of series resistance). The ratio of the inductance to the capacitance per unit length defines the characteristic impedance. At places where the extra capacitance of devices would cause an impedance change the line width is narrowed to reduce the capacitance per unit length and compensate (almost) for the extra loading. The controller sees a resistive impedance of 28 ohm, while the memory chips see an impedance of 14 ohm because they are driving two transmission lines, one going towards the controller and one going away from it. Those devices some distance away from the controller have no way of even knowing that the controller end of the line is open circuited because the whole of one bit can be transmitted before the beginning of that bit even reaches the end of the line. So even if the line were doubly terminated it would make no difference to the voltage delivered for a particular current. Hope this makes sense. John