Intel 815 - Manual (Page 15)

Introduction
R
Intel
®
815 Chipset Platform Design Guide 15
Term Description
Ringback The voltage that a signal rings back to after achieving its maximum absolute
value. Ringback may be due to reflections, driver oscillations, or other
transmission line phenomena.
Setup Window The time between the beginning of Setup to Clock (T
SU_MIN
) and the arrival of a
valid clock edge. This window may be different for each type of bus agent in the
system.
SSO Simultaneous Switching Output (SSO) Effects refers to the difference in electrical
timing parameters and degradation in signal quality caused by multiple signal
outputs simultaneously switching voltage levels (e.g., high-to-low) in the opposite
direction from a single signal (e.g., low-to-high) or in the same direction (e.g.,
high-to-low). These are respectively called odd-mode switching and even-mode
switching. This simultaneous switching of multiple outputs creates higher current
swings that may cause additional propagation delay (or “push-out”), or a decrease
in propagation delay (or “pull-in”). These SSO effects may impact the setup
and/or hold times and are not always taken into account by simulations. System
timing budgets should include margin for SSO effects.
Stub The branch from the bus trunk terminating at the pad of an agent.
System Bus The system bus is the processor bus.
Trunk The main connection, excluding interconnect branches, from one end agent pad
to the other end agent pad.
Undershoot Minimum voltage observed for a signal to extend below VSS at the device pad.
Universal Socket 370 Refers to the Intel 815 chipset using the “universal” PGA370 socket. In general,
these designs support 66/100/133 MHz system bus operation, VRM 8.5 DC-DC
converter guidelines, and Intel
® Celeron™ processors (CPUID=068xh), Intel ®
Pentium ® III processor (CPUID=068xh), and future Pentium III processors in
single-microprocessor based designs.
Victim A network that receives a coupled crosstalk signal from another network is called
the victim network.