54.14.4 GMAC Characteristics

Timing Conditions

Table 54-59. GMAC Load Capacitance on Data, Clock Pads
Symbol	Description	Condition	Min.	Max.	Units
C_L	Load Capacitance	V_DD=3.3V	0	20	pF

The GMAC must be constrained so as to satisfy the timings of standards given the following two tables, in MAX corner.

Figure 54-16. Minimum and Maximum Access Time of GMAC Output Signals

Table 54-60. Minimum and Maximum Access Time of GMAC Output Signals
Symbol	Parameter	Min.	Max.	Units
GMAC₁	Setup for GMDIO from GMDC rising	10	-	ns
GMAC₂	Hold for GMDIO from GMDC rising	10	-
GMAC₃	GMDIO toggling from GMDC falling	0⁽¹⁾	10⁽¹⁾

Note:

For GMAC output signals, min. and max. access times are defined:
- The min. access time is the time between the GMDC falling edge and the signal change.
- The max. access time is the time between the GMDC falling edge and the signal stabilizes.

Table 54-61. GMAC MII Mode Timings
Symbol	Parameter	Min	Max	Unit
GMAC₄	Setup for GCOL from GTXCK rising	10	–	ns
GMAC₅	Hold for GCOL from GTXCK rising	10	–
GMAC₆	Setup for GCRS from GTXCK rising	10	–
GMAC₇	Hold for GCRS from GTXCK rising	10	–
GMAC₈	GTXER toggling from GTXCK rising	10	25
GMAC₉	GTXEN toggling from GTXCK rising	10	25
GMAC₁₀	GTX toggling from GTXCK rising	10	25
GMAC₁₁	Setup for GRX from GRXCK	10	–
GMAC₁₂	Hold for GRX from GRXCK	10	–
GMAC₁₃	Setup for GRXER from GRXCK	10	–
GMAC₁₄	Hold for GRXER from GRXCK	10	–
GMAC₁₅	Setup for GRXDV from GRXCK	10	–
GMAC₁₆	Hold for GRXDV from GRXCK	10	–

Table 54-62. GMAC RMII Mode Timings
Symbol	Parameter	Min.	Max.	Units
GMAC₂₁	ETXEN toggling from EREFCK rising	2	16	ns
GMAC₂₂	ETX toggling from EREFCK rising	2	16
GMAC₂₃	Setup for ERX from EREFCK rising	4	-
GMAC₂₄	Hold for ERX from EREFCK rising	2	-
GMAC₂₅	Setup for ERXER from EREFCK rising	4	-
GMAC₂₆	Hold for ERXER from EREFCK rising	2	-
GMAC₂₇	Setup for ECRSDV from EREFCK rising	4	-
GMAC₂₈	Hold for ECRSDV from EREFCK rising	2	-