SLLS665M September 2005 – February 2023 SN65HVD30 , SN65HVD31 , SN65HVD32 , SN65HVD33 , SN65HVD34 , SN65HVD35
PRODUCTION DATA
When connecting a node to the bus, the distance between the transceiver inputs and the cable trunk, known as the stub, must be as short as possible. Stubs present a nonterminated piece of bus line that can introduce reflections as the length of the stub increases. As a general guideline, the electrical length, or round-trip delay, of a stub must be less than one-tenth of the rise time of the driver; thus giving a maximum physical stub length as shown in Equation 1.
where:
Per Equation 1, Table 9-1 shows the maximum cable-stub lengths for the minimum driver output rise times of the SN65HVD3x full-duplex family of transceivers for a signal velocity of 78%.
DEVICE | MINIMUM DRIVER OUTPUT RISE TIME (ns) | MAXIMUM STUB LENGTH | |
---|---|---|---|
(m) | (ft) | ||
SN65HVD30 | 4 | 0.1 | 0.3 |
SN65HVD31 | 25 | 0.6 | 1.9 |
SN65HVD32 | 120 | 2.8 | 9.2 |
SN65HVD33 | 4 | 0.1 | 0.3 |
SN65HVD34 | 25 | 0.6 | 1.9 |
SN65HVD35 | 120 | 2.8 | 9.2 |