ZHCSCM6G May 2014 – October 2019 SN65HVD70 , SN65HVD71 , SN65HVD73 , SN65HVD74 , SN65HVD76 , SN65HVD77
PRODUCTION DATA.
When connecting a node to the bus, the distance between the transceiver inputs and the cable trunk, known as the stub, should be as short as possible. Stubs present a non-terminated piece of bus line which can introduce reflections as the length of the stub increases. As a general guideline, the electrical length, or round-trip delay, of a stub should 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 5 lists the maximum cable-stub lengths for the minimum-driver output rise-times of the SN65HVD7x full-duplex family of transceivers for a signal velocity of 78%.
| DEVICE | MINIMUM DRIVER OUTPUT RISE TIME (ns) | MAXIMUM STUB LENGTH | |
|---|---|---|---|
| (m) | (ft) | ||
| SN65HVD70 | 100 | 2.34 | 7.7 |
| SN65HVD71 | 100 | 2.34 | 7.7 |
| SN65HVD73 | 4 | 0.1 | 0.3 |
| SN65HVD74 | 4 | 0.1 | 0.3 |
| SN65HVD76 | 2 | 0.05 | 0.15 |
| SN65HVD77 | 2 | 0.05 | 0.15 |