very hifh density metric (VHDM)
VHDM connectors (Very High Density Metric) are connectors with an extremely high pin density and metric dimensions. They are available in 6- and 8-row versions with shielding between the columns to reduce crosstalk.
The pin spacing of VHDM connectors is 2 mm between columns and 1.25 mm between rows. VHDM connectors can transmit data rates of 3.125 Gbit/s, and crosstalk is less than 5%. The 8-row version has 40 signal lines per 1 cm, while the 6-row version has 30. VHDM connectors are available in versions with 10 and 25 columns.
VHDM connectors are used in blade serverbackplanes and can carry supply currents of 10 A to server blades of 10 A. They are also found in data communications systems, industrial manufacturing systems, and medical and military equipment.