Datasheet
SN74VMEH22501
LVTTL-TO-ETL 8-BIT UNIVERSAL BUS TRANSCEIVER AND TWO 1-BIT BUS
TRANSCEIVERS WITH SPLIT LVTTL PORT, FEEDBACK PATH, AND 3-STATE OUTPUTS
SCES357A – JULY 2001 – REVISED SEPTEMBER 2001
6–27
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
simulation matrix
The simulation matrix of the adjustable-transceiver study shows the range of simulations to be carried out. Each
case might have a number of different simulation runs, for example, multiple rise times in search of the boundary
condition.
For cases 1 and 2 of the adjustable-transceiver study, the weak-driver high and/or low output current is
increased, if required, to find a case that works. If this is required, the strong-driver output current is increased,
based on TI’s defined percentage process variation from minimum to maximum, and these values are used in
subsequent cases for the weak and strong models.
All simulations are performed with the five-row DIN connector.
adjustable-transceiver study
CASE
BACKPLANE
LOADING
UNBALANCED
SIGNAL
DRIVING
SLOT
TRANSCEIVER
DRIVE
TRANSCEIVER
RISE/FALL TIME
LINE
(Ω)
MAX
FREQUENCY
(MHz)
LOADING STRENGTH
9-15-00 10-10-00
1
All slots
All lines 11 Weak
Find fastest that works
4 ns to 8 ns. If no case
works, increase weak
driver current until a
case works.
45 – 20
2
All slots
All lines 1 Weak
Find fastest that works
4 ns to 8 ns (start at
fastest that works
above). If no case
works, increase weak
driver current until a
case works.
45 20 20
3
All slots
All lines 1 Strong
Find fastest that works
4 ns to 8 ns (start at
fastest that works
above)
45 – 20
4
All slots
All lines 11 Strong
Find fastest that works
4 ns to 8 ns (start at
fastest that works
above)
45 – 20
5
Slots 11 and 12
All lines 11 Strong
Find fastest that works
4 ns to 8 ns (start at
fastest that works
above)
45 – 20
6
Slots 1 and 21
All lines 1 Strong
Find fastest that works
4 ns to 8 ns (start at
fastest that works
above)
45 – 20
7
Slots 1, 11, and
17–21
All lines 1 Strong
Find fastest that works
4 ns to 8 ns (start at
fastest that works
above)
45 20 20
PRODUCT PREVIEW