Add script for calculating AP61302 parameters

Author: jackpot51

pcb/scripts/ap61302.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python3
+
+# Values from AP61302
+## VOUT reference voltage (0.6V)
+VOUT_REF = 0.6
+## Switching frequency (2.2 MHz)
+FSW = 2.2e6
+
+# Values from PCB
+## USB voltage (5V)
+VIN = 5.0
+## Inductor value (2.2 uH)
+L = 2.2e-6
+## Output capacitor value (22 uF)
+COUT = 22.0e-6
+## Capacitor ESR (ESTIMATED 500 mOhm)
+ESR = 500.0e-3
+## Resistor 1 values (9.1 kOhm, 52.3 kOhm)
+R1S = [9.1e3, 52.3e3]
+## Resistor 2 value (10 kOhm)
+R2 = 10.0e3
+
+for R1 in R1S:
+    VOUT = VOUT_REF + (VOUT_REF * R1) / R2
+    DELTA_IL = (VOUT * (VIN - VOUT)) / (VIN * FSW * L)
+    VOUT_RIPPLE = DELTA_IL * (ESR + 1.0 / (8.0 * FSW * COUT))
+    print(
+            "VOUT", VOUT,
+            "DELTA_IL", DELTA_IL,
+            "VOUT_RIPPLE", VOUT_RIPPLE
+    )