diff --git a/Makefile b/Makefile
index 7c5010f..4f3d2c9 100644
--- a/Makefile
+++ b/Makefile
@@ -67,7 +67,7 @@
 endif
 
 ifeq ($(PDK),gf180mcuC)
-	MPW_TAG ?= gfmpw-0a
+	MPW_TAG ?= gfmpw-0b
 	CARAVEL_NAME := caravel
 	CARAVEL_REPO := https://github.com/efabless/caravel-gf180mcu
 	CARAVEL_TAG := $(MPW_TAG)