diff --git a/smoothie/smoothie.d.ts b/smoothie/smoothie.d.ts
index 3353c3dbfe..aae781d51d 100644
--- a/smoothie/smoothie.d.ts
+++ b/smoothie/smoothie.d.ts
@@ -113,6 +113,10 @@ declare module "smoothie"
         scaleSmoothing?: number;
         /** Sets the speed at which the chart pans by. */
         millisPerPixel?: number;
+        /** Whether to render at different DPI depending upon the device. Enabled by default. */
+        enableDpiScaling?: boolean;
+        yMinFormatter?: (min:number, precision:number)=>string;
+        yMaxFormatter?: (max:number, precision:number)=>string;
         maxDataSetLength?: number;
         /** One of: 'bezier', 'linear', 'step' */
         interpolation?: string;