diff --git a/artiq/coredevice/ad53xx.py b/artiq/coredevice/ad53xx.py
index 1f6984108..6ab325717 100644
--- a/artiq/coredevice/ad53xx.py
+++ b/artiq/coredevice/ad53xx.py
@@ -41,8 +41,8 @@ class AD53xx:
                  chip_select=0, write_div=4, read_div=6):
         self.core = dmgr.get("core")
         self.bus = dmgr.get(spi_bus)
-        # if ldac is not None:
-        ldac = dmgr.get(ldac)
+        if ldac is not None:
+            ldac = dmgr.get(ldac)
         self.ldac = ldac
         self.chip_select = chip_select
         self.write_div = write_div