SNLS579A April 2018 – November 2018 DP83TC811S-Q1
If sleep enable is set, the PHY transitions to sleep mode after silent_timer expires; however, if sleep enable is not set, the device transitions to standby once silent_timer expires. By default, sleep enable is set. Once in sleep mode, all PHY blocks are disabled except for energy detection on the MDI. All register configurations are lost in sleep mode. No link can be established, data cannot be transmitted or received and SMI access is not available when in sleep mode.