LVCMOS

UltraScale Architecture SelectIO Resources User Guide (UG571)

Document ID
UG571
Release Date
2022-08-31
Revision
1.14 English
Table 1-18:      Available I/O Bank Type 

HR

HP

Available

Available

Low voltage CMOS (LVCMOS) is a widely used switching standard implemented in CMOS transistors. This standard is defined by JESD8-12A.01, JESD8-11A.01, JESD8-7A, JESD8-5A.01, and JESD8C.01 [Ref 7]. The LVCMOS standards supported in UltraScale devices are: LVCMOS12, LVCMOS15, LVCMOS18, LVCMOS25, and LVCMOS33.

Sample circuits illustrating both unidirectional and bidirectional LVCMOS termination techniques are shown in This Figure and This Figure. These two diagrams show examples of source-series and parallel terminated topologies.

This Figure shows unidirectional terminated topologies.

Figure 1-49:      LVCMOS Unidirectional Termination

X-Ref Target - Figure 1-49

X16109-lvcmos-uni-term.jpg

This Figure shows a bidirectional, parallel-terminated topology.

Figure 1-50:      LVCMOS Bidirectional Termination

X-Ref Target - Figure 1-50

X16110-lvcmos-bidi-term.jpg

Table: Allowed Attributes for the LVCMOS33 and LVCMOS25 I/O Standards  details the allowed attributes that can be applied to the LVCMOS33 and LVCMOS25 I/O standards. These standards are only available in the HR I/O banks. Support is implied for primitives that are derivatives of the primitives listed in Table: Allowed Attributes for the LVCMOS33 and LVCMOS25 I/O Standards  (for example: *_DIFF_OUT, *_DCIEN, *_IBUFDISABLE, or *_INTERMDISABLE). Refer to the SelectIO Interface Primitives section for all supported derivatives.

Table 1-19:      Allowed Attributes for the LVCMOS33 and LVCMOS25 I/O Standards 

Attributes

Primitives

IBUF

OBUF/OBUFT/IOBUF

Allowed Values

Default

IOSTANDARD

LVCMOS33, LVCMOS25

LVCMOS33, LVCMOS25

DRIVE

N/A

4, 8, 12, or 16

12

SLEW

N/A

FAST or SLOW

SLOW

Table: Allowed Attributes for the LVCMOS18 I/O Standard  details the allowed attributes that can be applied to the LVCMOS18 I/O standard. This standard is available in both the HR and HP I/O banks. For MOBILE DDR applications, the LVCMOS18 I/O standard is used with an 8 mA unterminated drive. Support is implied for primitives that are derivatives of the primitives listed in Table: Allowed Attributes for the LVCMOS18 I/O Standard  (for example: *_DIFF_OUT, *_DCIEN, *_IBUFDISABLE, or *_INTERMDISABLE). Refer to the SelectIO Interface Primitives section for all supported derivatives.

Table 1-20:      Allowed Attributes for the LVCMOS18 I/O Standard 

Attributes

Primitives

IBUF

OBUF/OBUFT/IOBUF

HP I/O Banks

HR I/O Banks

Allowed Values

Default

Allowed Values

Default

IOSTANDARD

LVCMOS18

LVCMOS18

LVCMOS18

DRIVE

N/A

2, 4, 6, 8, 12

12

4, 8, 12, 16

12

SLEW

N/A

FAST, MEDIUM, SLOW

SLOW

FAST, SLOW

SLOW

Table: Allowed Attributes for the LVCMOS15 I/O Standard  details the allowed attributes that can be applied to the LVCMOS15 I/O standard. This standard is available in both the HR and HP I/O banks. Support is implied for primitives that are derivatives of the primitives listed in Table: Allowed Attributes for the LVCMOS15 I/O Standard  (for example: *_DIFF_OUT, *_DCIEN, *_IBUFDISABLE, or *_INTERMDISABLE). Refer to the SelectIO Interface Primitives section for all supported derivatives.

Table 1-21:      Allowed Attributes for the LVCMOS15 I/O Standard 

Attributes

Primitives

IBUF

OBUF/OBUFT/IOBUF

HP I/O Banks

HR I/O Banks

Allowed Values

Default

Allowed Values

Default

IOSTANDARD

LVCMOS15

LVCMOS15

LVCMOS15

DRIVE

N/A

2, 4, 6, 8, 12

12

4, 8, 12, 16

12

SLEW

N/A

FAST, MEDIUM, SLOW

SLOW

FAST, SLOW

SLOW

Table: Allowed Attributes for the LVCMOS12 I/O Standard  details the allowed attributes that can be applied to the LVCMOS12 I/O standard. This standard is available in both the HR and HP I/O banks. Support is implied for primitives that are derivatives of the primitives listed in Table: Allowed Attributes for the LVCMOS12 I/O Standard  (for example: *_DIFF_OUT, *_DCIEN, *_IBUFDISABLE, or *_INTERMDISABLE). Refer to the SelectIO Interface Primitives section for all supported derivatives.

Table 1-22:      Allowed Attributes for the LVCMOS12 I/O Standard 

Attributes

Primitives

IBUF

OBUF/OBUFT/IOBUF

HP I/O Banks

HR I/O Banks

Allowed Values

Default

Allowed Values

Default

IOSTANDARD

LVCMOS12

LVCMOS12

LVCMOS12

DRIVE

N/A

2, 4, 6, 8

12(1)

4, 8, 12

12

SLEW

N/A

FAST, MEDIUM, SLOW

SLOW

FAST, SLOW

SLOW

Notes:

1.Change the drive setting from the default setting in the RTL or XDC file to one of the allowed values before running through the Vivado Design Suite.