diff --git a/techlibs/ecp5/cells_sim.v b/techlibs/ecp5/cells_sim.v
index f66147323..0239d1afe 100644
--- a/techlibs/ecp5/cells_sim.v
+++ b/techlibs/ecp5/cells_sim.v
@@ -106,7 +106,7 @@ module PFUMX (input ALUT, BLUT, C0, output Z);
 endmodule
 
 // ---------------------------------------
-//(* abc_box_id=2 *)
+(* abc_box_id=2, abc_scc_break="DI" *)
 module TRELLIS_DPR16X4 (
 	input [3:0] DI,
 	input [3:0] WAD,