Preliminary support in Magic for ReRAM. Putting this support in
sky130A is a temporary solution, as the ReRAM metal stackup is
different (mainly with respect to parasitics) and requires that
there be a new variant sky130B supporting ReRAM and the altered
stackup. The temporary solution will allow people to design
ReRAM based projects while we revise parasitics for the stackup.
diff --git a/sky130/magic/sky130.tech b/sky130/magic/sky130.tech
index 2250bf9..8582abd 100644
--- a/sky130/magic/sky130.tech
+++ b/sky130/magic/sky130.tech
@@ -252,6 +252,10 @@
metal1 padl
-metal1 m1fill
+#ifdef RERAM
+ metal2 reram,rr
+#endif
+
# Metal 2
metal2 metal2,m2,met2
metal2 rmetal2,rm2,rmet2
@@ -448,7 +452,11 @@
allli *locali,coreli,rli
allm1 *m1,rm1
+#ifdef RERAM
+ allm2 *m2,rm2,reram
+#else (!RERAM)
allm2 *m2,rm2
+#endif (!RERAM)
allm3 *m3,rm3
#ifdef METAL5
allm4 *m4,rm4
@@ -575,6 +583,11 @@
rm1 metal2 poly_resist_stripes
obsm1 metal2
m2c metal2 metal3 via2arrow
+
+#ifdef RERAM
+ reram metal2 metal3 via2 contact_X'es
+#endif (RERAM)
+
metal2 metal3
m2fill metal3
rm2 metal3 poly_resist_stripes
@@ -700,7 +713,11 @@
pwell,*psd,*mvpsd,npn pwell,*psd,*mvpsd,npn
*li,coreli,lifill *li,coreli,lifill
*m1,m1fill,obsmcon *m1,m1fill,obsmcon
+#ifdef RERAM
+ *m2,m2fill,reram *m2,m2fill,reram
+#else (!RERAM)
*m2,m2fill *m2,m2fill
+#endif (!RERAM)
*m3,m3fill *m3,m3fill
#ifdef METAL5
*m4,m4fill *m4,m4fill
@@ -1247,6 +1264,14 @@
squares-grid 40 200 200
calma 69 44
+#ifdef RERAM
+#undef RERAM
+ layer RERAM reram
+ squares-grid 55 230 230
+ calma 201 20
+#define RERAM
+#endif (RERAM)
+
#----------------------------------------------------------------
# MET3
#----------------------------------------------------------------
@@ -3511,8 +3536,17 @@
#endif (MIM)
+#ifdef RERAM
+ layer reram RERAM
+ and VIA1
+ grow 55
+#endif (RERAM)
+
templayer m2cbase VIA1
and-not COREID
+#ifdef RERAM
+ and-not RERAM
+#endif (RERAM)
grow 5
or VIA1
grow 50
@@ -3957,6 +3991,9 @@
calma MET1 68 20
calma VIA1 68 44
+#ifdef RERAM
+ calma RERAM 201 20
+#endif (RERAM)
calma MET2 69 20
calma VIA2 69 44
calma MET3 70 20
@@ -4526,6 +4563,22 @@
exact_overlap v1/m1
+#ifdef RERAM
+#--------------------------------------------------
+# ReRAM
+#--------------------------------------------------
+
+ width reram 340 "ReRAM width < %d (rr1.1)"
+ spacing reram reram 55 touching_illegal "ReRAM spacing < %d (rr1.2)"
+ surround reram *m1,rm1 30 directional \
+ "Metal1 overlap of ReRAM < %d in one direction (via.5a - via.4a)"
+ surround reram *m2,rm2 30 directional \
+ "Metal2 overlap of ReRAM < %d in one direction (met2.5 - met2.4)"
+
+ no_overlap reram,v1 reram,v1
+
+#endif (RERAM)
+
#--------------------------------------------------
# METAL2 -
#--------------------------------------------------
@@ -4991,6 +5044,9 @@
height mcon 1.0361 0.34
height allm1 1.3761 0.36
height m1fill 1.3761 0.36
+#ifdef RERAM
+ # TO-DO: Rework all heights based on ReRAM!
+#endif (RERAM)
height v1 1.7361 0.27
height allm2 2.0061 0.36
height m2fill 1.3761 0.36
@@ -5176,6 +5232,10 @@
defaultsideoverlap allm1 metal1 allli locali 59
defaultsideoverlap allli locali allm1 metal1 35
+#ifdef RERAM
+# TO-DO: Modify all metal stack parasitics above metal1 based on ReRAM!
+#endif (RERAM)
+
#metal2
defaultsidewall allm2 metal2 50
defaultareacap allm2 metal2 nwell,obswell,pwell well 17
@@ -5465,6 +5525,10 @@
device ndiode sky130_fd_pr__diode_pw2nd_05v5_nvt *nndiode pwell,space/w a=area p=pj
device ndiode sky130_fd_pr__diode_pw2nd_11v0 *mvndiode pwell,space/w a=area p=pj
+#ifdef RERAM
+ device csubcircuit sky130_fd_pr__reram reram m1 a=area_ox
+#endif (RERAM)
+
#ifdef MIM
device csubcircuit sky130_fd_pr__cap_mim_m3_1 *mimcap *m3 w=w l=l
device csubcircuit sky130_fd_pr__cap_mim_m3_2 *mimcap2 *m4 w=w l=l
