Jon Keeble wrote:
> I've seen one or two interesting approaches to controlling edge speeds.
>
> The first was a method of controlling the edge speed:
> The Analog Devices 21020 DSP chip has an external resistor for setting
> edge speeds (all outputs). I've no idea how this works internally.
>
> The other method reduced the production spread of edge speeds:
> It seems that the parts that run faster also have faster edges.
> The method involved
> - an onboard oscillator that ran at a speed determined by the speed of
> the device
> - internal control on the output drivers to vary the edge speed
> - a circuit that translated the oscillator speed to more or less drive
> on the outputs
>
> As a designer, it is obvious tpo me that there is a real need for
> control over edge speeds.
>
> I find it really exhausting to have to add hundreds of external
> resistors, not to mention the additional costs, numbers of parts,
> numbers of nodes to test etc etc.
>
> I'd encourage the IC designers to be a bit more inventive.
>
> Jon Keeble.
>
> **** To unsubscribe from si-list: send e-mail to [email protected]. In the BODY of message put: UNSUBSCRIBE si-list, for more help, put HELP. si-list archives are accessible at http://www.qsl.net/wb6tpu/si-list ****
-- Philip R. Gantt [email protected] . . Phone : (408) 527-2918 | | Fax : (408) 526-5504 ||| ||| Pager : (408) 814-8868 ||||| ||||| 170 West Tasman Drive, SJ-G2 ||||||||| ||||||||| San Jose, CA 95134-1706 (U.S.A.) .:|||||||||||||||||||||||||:.
**** To unsubscribe from si-list: send e-mail to [email protected]. In the BODY of message put: UNSUBSCRIBE si-list, for more help, put HELP. si-list archives are accessible at http://www.qsl.net/wb6tpu/si-list ****