Add noise floor images with on-board regulator

README.md

@@ -44,13 +44,23 @@ Click the image to open interactive version in Paul Falstad's excellent online s
 
 ## Screenshots
 
-Please note that all these are with **AMS-1117** linear voltage regulator replacing the stock switched regulator on Pico. This is done by jumpering `3V3_EN` pin to `GND`, feeding `VSYS` to the regulator input and passing the regulator output to `3V3` pin. The `3V3` rail is then decoupled with `10uF` ceramic capacitor to `GND` on the analog board.
+Please note that screenshots are with **AMS-1117** linear voltage regulator bypassing the Picos RT6150 on-board switching regulator unless the caption says otherwise. This is done by jumpering `3V3_EN` pin to `GND`, feeding `VSYS` to the regulator input and passing the regulator output to `3V3` pin. The `3V3` rail is then decoupled with `10uF` ceramic capacitor to `GND` on the analog board.
 
 <details>
-  <summary>Noise Floor</summary>
+  <summary>Noise floor with external AMS-1117 linear regulator</summary>
   <img src="images/noise-floor.png" width="956" />
 </details>
 
+<details>
+  <summary>Noise floor with on-board RT6150 SMPS in <b>PWM</b> mode</summary>
+  <img src="images/noise-floor-pwm.png" width="956" />
+</details>
+
+<details>
+  <summary>Noise floor with on-board RT6150 SMPS in <b>PFM</b> mode</summary>
+  <img src="images/noise-floor-pfm.png" width="956" />
+</details>
+
 <details>
   <summary>IR Blast, full rate</summary>
   <img src="images/ir-blast-full.png" width="956" />