diff --git a/src/frontend/inpcom.c b/src/frontend/inpcom.c
index 8099347d3..16fea8644 100644
--- a/src/frontend/inpcom.c
+++ b/src/frontend/inpcom.c
@@ -2490,6 +2490,8 @@ static int is_a_modelname(char *s, const char* line)
         case 'P':
         case 'f':
         case 'F':
+        case 'a':
+        case 'A':
             st = st + 1;
             break;
         case 'm':
diff --git a/src/frontend/numparam/xpressn.c b/src/frontend/numparam/xpressn.c
index fd0749bc3..2a59f807d 100644
--- a/src/frontend/numparam/xpressn.c
+++ b/src/frontend/numparam/xpressn.c
@@ -610,6 +610,7 @@ parseunit(const char *s)
     case 'N':  return 1e-9;
     case 'P':  return 1e-12;
     case 'F':  return 1e-15;
+    case 'A':  return 1e-18;
     default :  return 1;
     }
 }
diff --git a/src/frontend/parser/numparse.c b/src/frontend/parser/numparse.c
index ccb2d5e83..3ea6c62d6 100644
--- a/src/frontend/parser/numparse.c
+++ b/src/frontend/parser/numparse.c
@@ -95,6 +95,11 @@ int ft_numparse(char **p_str, bool whole, double *p_val)
         expo = -15.0;
         ++p_cur;
         break;
+    case 'a':
+    case 'A':
+        expo = -18.0;
+        ++p_cur;
+        break;
     case 'm':
     case 'M': {
         char ch_cur;
diff --git a/src/spicelib/parser/inpeval.c b/src/spicelib/parser/inpeval.c
index 8e8b24c9b..13dcaa81b 100644
--- a/src/spicelib/parser/inpeval.c
+++ b/src/spicelib/parser/inpeval.c
@@ -169,6 +169,10 @@ INPevaluate(char **line, int *error, int gobble)
     case 'F':
         expo1 = expo1 - 15;
         break;
+    case 'a':
+    case 'A':
+        expo1 = expo1 - 18;
+        break;
     case 'm':
     case 'M':
         if (((here[1] == 'E') || (here[1] == 'e')) &&
@@ -626,6 +630,10 @@ INPevaluateRKM_C(char** line, int* error, int gobble)
         expo1 = expo1 - 15;
         hasmulti = TRUE;
         break;
+    case 'a':
+    case 'A':
+        expo1 = expo1 - 18;
+        break;
     case 'm':
     case 'M':
         if (((here[1] == 'E') || (here[1] == 'e')) &&
@@ -860,6 +868,10 @@ INPevaluateRKM_L(char** line, int* error, int gobble)
         expo1 = expo1 - 15;
         hasmulti = TRUE;
         break;
+    case 'a':
+    case 'A':
+        expo1 = expo1 - 18;
+        break;
     case 'm':
     case 'M':
         if (((here[1] == 'E') || (here[1] == 'e')) &&
diff --git a/src/xspice/icm/digital/d_source/cfunc.mod b/src/xspice/icm/digital/d_source/cfunc.mod
index da428c4a5..716ebb387 100644
--- a/src/xspice/icm/digital/d_source/cfunc.mod
+++ b/src/xspice/icm/digital/d_source/cfunc.mod
@@ -429,6 +429,10 @@ double  *p_value )   /* OUT - The numerical value     */
             scale_factor = 1.0e-15;
             break;
 
+        case 'a':
+            scale_factor = 1.0e-18;
+            break;
+
         case 'm':
             i++;
             if(i >= len) {
diff --git a/src/xspice/icm/digital/d_state/cfunc.mod b/src/xspice/icm/digital/d_state/cfunc.mod
index 472738f98..4666e8b8d 100644
--- a/src/xspice/icm/digital/d_state/cfunc.mod
+++ b/src/xspice/icm/digital/d_state/cfunc.mod
@@ -441,6 +441,10 @@ double  *p_value )   /* OUT - The numerical value     */
             scale_factor = 1.0e-15;
             break;
 
+        case 'a':
+            scale_factor = 1.0e-18;
+            break;
+
         case 'm':
             i++;
             if(i >= len) {