diff --git a/src/db/db/built-in-macros/pcell_declaration_helper.lym b/src/db/db/built-in-macros/pcell_declaration_helper.lym
index 43754b65d..ba97fac7d 100644
--- a/src/db/db/built-in-macros/pcell_declaration_helper.lym
+++ b/src/db/db/built-in-macros/pcell_declaration_helper.lym
@@ -118,6 +118,12 @@ Optional, named parameters are
   @li 
     @b:unit@/b: the unit string
   @/li
+  @li 
+    @b:min_value@/b: the minimum value (effective for numerical types and if no choices are present)
+  @/li
+  @li 
+    @b:max_value@/b: the maximum value (effective for numerical types and if no choices are present)
+  @/li
   @li 
     @b:default@/b: the default value
   @/li
@@ -335,6 +341,8 @@ module RBA
     #   :hidden      -> (boolean) true, if the parameter is not shown in the dialog
     #   :readonly    -> (boolean) true, if the parameter cannot be edited
     #   :unit        -> the unit string
+    #   :min_value   -> the minimum value (only effective for numerical types and if no choices are present)
+    #   :max_value   -> the maximum value (only effective for numerical types and if no choices are present)
     #   :default     -> the default value
     #   :choices     -> ([ [ d, v ], ...) choice descriptions/value for choice type
     # this method defines accessor methods for the parameters
@@ -373,6 +381,8 @@ module RBA
       args[:hidden] && pdecl.hidden = args[:hidden]
       args[:readonly] && pdecl.readonly = args[:readonly]
       args[:unit] && pdecl.unit = args[:unit]
+      args[:min_value] && pdecl.min_value = args[:min_value]
+      args[:max_value] && pdecl.max_value = args[:max_value]
       if args[:choices]
         if !args[:choices].is_a?(Array)
           raise ":choices value must be an array of two-element arrays (description, value)"
diff --git a/src/db/db/built-in-pymacros/pcell_declaration_helper.lym b/src/db/db/built-in-pymacros/pcell_declaration_helper.lym
index 462883154..2b3113ca0 100644
--- a/src/db/db/built-in-pymacros/pcell_declaration_helper.lym
+++ b/src/db/db/built-in-pymacros/pcell_declaration_helper.lym
@@ -127,6 +127,12 @@ Optional, named parameters are
   @li 
     @bunit@/b: the unit string
   @/li
+  @li 
+    @bmin_value@/b: the minimum value (effective for numerical types and if no choices are present)
+  @/li
+  @li 
+    @bmax_value@/b: the maximum value (effective for numerical types and if no choices are present)
+  @/li
   @li 
     @bdefault@/b: the default value
   @/li
diff --git a/src/pymod/distutils_src/klayout/db/pcell_declaration_helper.py b/src/pymod/distutils_src/klayout/db/pcell_declaration_helper.py
index 5bdb73e4e..5beff2043 100644
--- a/src/pymod/distutils_src/klayout/db/pcell_declaration_helper.py
+++ b/src/pymod/distutils_src/klayout/db/pcell_declaration_helper.py
@@ -66,7 +66,7 @@ class _PCellDeclarationHelperMixin:
     self.layer = None
     self.cell = None
 
-  def param(self, name, value_type, description, hidden = False, readonly = False, unit = None, default = None, choices = None):
+  def param(self, name, value_type, description, hidden = False, readonly = False, unit = None, default = None, choices = None, min_value = None, max_value = None):
     """
     Defines a parameter
       name         -> the short name of the parameter
@@ -76,6 +76,8 @@ class _PCellDeclarationHelperMixin:
       hidden      -> (boolean) true, if the parameter is not shown in the dialog
       readonly    -> (boolean) true, if the parameter cannot be edited
       unit        -> the unit string
+      min_value   -> the minimum value (only effective for numerical types and if no choices are present)
+      max_value   -> the maximum value (only effective for numerical types and if no choices are present)
       default     -> the default value
       choices     -> ([ [ d, v ], ...) choice descriptions/value for choice type
     this method defines accessor methods for the parameters
@@ -102,6 +104,8 @@ class _PCellDeclarationHelperMixin:
     pdecl.readonly = readonly
     if not (default is None):
       pdecl.default = default
+    pdecl.min_value = min_value
+    pdecl.max_value = max_value
     if not (unit is None):
       pdecl.unit = unit
     if not (choices is None):