External Memory Interface Handbook Volume 3: Reference Material: For UniPHY-based Device Families

ID 683841
Date 3/06/2023
Public
Document Table of Contents

5.4.1. Clock and Reset Interface

The clock and reset interface is part of the AFI interface.

The controller can have up to two clock domains, which are synchronous to each other. The controller operates with a single clock domain when there is no integrated half-rate bridge, and with two-clock domains when there is an integrated half-rate bridge. The clocks are provided by UniPHY.

The main controller clock is afi_clk, and the optional half-rate controller clock is afi_half_clk. The main and half-rate clocks must be synchronous and have a 2:1 frequency ratio. The optional quarter-rate controller clock is afi_quarter_clk, which must also be synchronous and have a 4:1 frequency ratio.