diff --git a/sky130/Makefile.in b/sky130/Makefile.in
index 78c7080..c78bdcb 100644
--- a/sky130/Makefile.in
+++ b/sky130/Makefile.in
@@ -370,9 +370,13 @@
 		-lef %l/latest/cells/*/*.magic.lef compile-only \
 		-spice %l/latest/cells/*/*.spice filter=custom/scripts/rename_cells.py \
 		-library primitive sky130_fd_pr |& tee -a ${SKY130A}_install.log
-	# Custom:  Add "short" resistor model to the r+c models file
+	# Custom:  Add "short" resistor model and subcircuit to the r+c models file
 	cat ./custom/models/short.spice >> \
 		${STAGING_PATH}/${SKY130A}/libs.tech/ngspice/sky130_fd_pr__model__r+c.model.spice 
+	# Custom:  Add diodes as subcircuits to the r+c models file
+	cat ./custom/models/diode.spice >> \
+		${STAGING_PATH}/${SKY130A}/libs.tech/ngspice/sky130_fd_pr__model__r+c.model.spice 
+
 	# Install custom additions to I/O pad library
 	${STAGE} -source ./custom -target ${STAGING_PATH}/${SKY130A} \
 		-verilog %l/verilog/*.v \
diff --git a/sky130/custom/models/diode.spice b/sky130/custom/models/diode.spice
new file mode 100644
index 0000000..81bee35
--- /dev/null
+++ b/sky130/custom/models/diode.spice
@@ -0,0 +1,9 @@
+* For diodes called as a subcircuit
+* (backwards compatible with earlier PDK version)
+.subckt sky130_fd_pr__diode_pw2nd N P a=0 p=0
+D0 N P sky130_fd_pr__diode_pw2nd_05v5 area=a
+.ends
+* (corresponds to current PDK)
+.subckt sky130_fd_pr__diode_pw2nd_05v5 N P area=0
+D0 N P sky130_fd_pr__diode_pw2nd_05v5 area=area
+.ends
diff --git a/sky130/custom/models/short.spice b/sky130/custom/models/short.spice
index bc5faf0..30df356 100644
--- a/sky130/custom/models/short.spice
+++ b/sky130/custom/models/short.spice
@@ -1,2 +1,6 @@
 * Resistor model "short" defined with a fixed resistance of 0.01 ohms.
 .model short r r=0.01
+* If "short" is called as a subcircuit, then this needs to be supported, too.
+.subckt short 1 2 SUB l=0 w=0
+R0 1 2 short
+.ends