IEEE 2401-2019 pdf free download

IEEE 2401-2019 pdf free download.IEEE Standard Format for LSI-Package Board Interoperable Design.
8.2.5.12.5.2 Attribute definitions
The attributes of the <skew> element are defined as follows. port_name
This attribute specifies the name of a predetined port for inputting and outputting a signal that requests a skew constraint. The specified port shall be defined at the <port> element in the same <socket> element. The port_name attribute shall not be used with the port_id nor group_name attributes.
port_id
This attribute specifics thc idcntificr of a prcdefincd port for inputting and outputting a signal that requests a skew constraint. The specified port shall be defined at the <port> element in the same <socket> element. The port_id attribute shall not be used with the port_name nor group_name attributes.
group_name
This attribute specifies the name of a group that includes ports for inputting and outputting a signal that requests a skew constraint. The specified port group shall be defined at the <portgroup> element in the same <socket> element. The group_name attribute shall not be used with the port_name nor port_id attributes.
re fe rence_port name
This attribute specifies the name of a predefined port for inputting and outputting a reference signal for a skew constraint. The specified port shall be defined at the <port> element in the same <socket> element. The reference_port_name attribute shall not be used with the reference_port_id attribute.
reference_port_id
This attribute specifies the identifier of a predefined port for inputting and outputting a reference signal for a skew constraint. The specified port shall be defined at the <port> element in the same <socket> element. The reference_port_id attribute shall not be used with the referenceyortid attribute.
mm
max
The max and mm attributes specify maximum and minimum skew time, respectively. Set a positive value for the max attribute and a negative value for the mm attribute. When a reference signal is specified by reference port name or reference port id attribute. mm and max attributes shall be used together. When a reference signal is not specified, either mm or max attribute shall be used. The unit of minimum and maximum skew time is defined by the <t- ime> element in the <unit> element.
8.2.5.12.5.3 Example
Assume that a semiconductor designer delivers a chip with a differential skew constraint. The following code is an example of a difThrcntial skew constraint of 10 Ps provided by a semiconductor designer. The package designer routes differential signal according to this constraint.IEEE 2401-2019 pdf free download.