From 4ee26c2763e45dd0d6cc6896a41423ee306a9b4f Mon Sep 17 00:00:00 2001
From: dagangtj <2285648311@qq.com>
Date: Fri, 27 Feb 2026 01:29:43 +1100
Subject: [PATCH] feat: implement WSON footprint

- Add wson.ts for WSON (Very Very Thin Small Outline No-lead) package
- Similar to SON/DFN with thermal pad support
- Common for TI power management ICs like TPS746
- Closes #73
---
 src/fn/index.ts |  1 +
 src/fn/wson.ts  | 28 ++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 src/fn/wson.ts

diff --git a/src/fn/index.ts b/src/fn/index.ts
index c3ee18a1..8ca07c07 100644
--- a/src/fn/index.ts
+++ b/src/fn/index.ts
@@ -80,3 +80,4 @@ export { sot343 } from "./sot343"
 export { m2host } from "./m2host"
 export { mountedpcbmodule } from "./mountedpcbmodule"
 export { to92l } from "./to92l"
+export { wson } from "./wson"
diff --git a/src/fn/wson.ts b/src/fn/wson.ts
new file mode 100644
index 00000000..0a6f05da
--- /dev/null
+++ b/src/fn/wson.ts
@@ -0,0 +1,28 @@
+import type { AnySoupElement } from "circuit-json"
+import { base_quad_def, quad, quadTransform } from "./quad"
+import type { z } from "zod"
+
+/**
+ * WSON (Very Very Thin Small Outline No-lead) footprint
+ * Similar to SON/DFN but typically with exposed thermal pad
+ * Common for TI power management ICs
+ */
+export const wson_def = base_quad_def.extend({}).transform(quadTransform)
+
+export const wson = (
+  parameters: z.input<typeof wson_def>,
+): { circuitJson: AnySoupElement[]; parameters: any } => {
+  parameters.legsoutside = false
+  // WSON typically has thermal pad
+  if (parameters.thermalpad === undefined) {
+    parameters.thermalpad = true
+  }
+  // Default pad dimensions for WSON if not specified
+  if (!parameters.pl) {
+    parameters.pl = 0.5
+  }
+  if (!parameters.pw) {
+    parameters.pw = 0.25
+  }
+  return quad(parameters)
+}