Compaq 4000S Personal Computer User Manual


 
Chapter 4 System Support
Compaq Deskpro 4000N and 4000S Personal Computers
First Edition - September 1997
4-14
The following guidelines apply to optional ISA devices installed in the system:
On bus lines that can be driven by a controller board, the driver should be able to sink a
minimum of 20 ma at 0.5 VDC and source 2 ma at 3.75 VDC.
On bus lines that are driven in the low direction only (open collector), the driver should be
able to sink 20 ma at 0.5 VDC.
The load on any logic line from a single bus slot should not exceed 2.0 ma in the low state
(at 0.5 VDC) or 0.1 ma in the high state (at 3.75 VDC).
The logic-high voltage at the bus ranges from 3.75 VDC to 5.5 VDC. The logic low voltage
ranges from 0 VDC to 0.8 VDC.