diff --git a/libraries/io/ddr/src/vhdl/io_ddr_driver.vhd b/libraries/io/ddr/src/vhdl/io_ddr_driver.vhd
index 549c1ee29449c7255cd7c0b55851b7f8fdd63541..dab999a6957edb6224ba5579fe23c30622183869 100644
--- a/libraries/io/ddr/src/vhdl/io_ddr_driver.vhd
+++ b/libraries/io/ddr/src/vhdl/io_ddr_driver.vhd
@@ -22,6 +22,7 @@
 
 LIBRARY IEEE, tech_ddr_lib, common_lib;
 USE IEEE.STD_LOGIC_1164.ALL;
+USE IEEE.NUMERIC_STD.ALL;
 USE common_lib.common_pkg.ALL;
 USE tech_ddr_lib.tech_ddr_pkg.ALL;