Merge pull request #178 from Neotron-Compute/fix-dac

Fix DAC

Author: thejpster

Kicad/bmc.kicad_sch

@@ -4980,7 +4980,7 @@
     (property "Footprint" "Package_TO_SOT_SMD:SOT-23" (at 249.555 140.335 0)
       (effects (font (size 1.27 1.27) italic) (justify left) hide)
     )
-    (property "Datasheet" "https://datasheet.lcsc.com/lcsc/1810151612_Jiangsu-Changjing-Electronics-Technology-Co---Ltd--2N7002_C8545.pdf" (at 244.475 138.43 0)
+    (property "Datasheet" "https://www.onsemi.com/pub/Collateral/NDS7002A-D.PDF" (at 244.475 138.43 0)
       (effects (font (size 1.27 1.27)) (justify left) hide)
     )
     (property "DNP" "0" (at 244.475 138.43 0)
@@ -5333,7 +5333,7 @@
     (property "Footprint" "Package_TO_SOT_SMD:SOT-23" (at 217.805 140.335 0)
       (effects (font (size 1.27 1.27) italic) (justify left) hide)
     )
-    (property "Datasheet" "https://datasheet.lcsc.com/lcsc/1810151612_Jiangsu-Changjing-Electronics-Technology-Co---Ltd--2N7002_C8545.pdf" (at 212.725 138.43 0)
+    (property "Datasheet" "https://www.onsemi.com/pub/Collateral/NDS7002A-D.PDF" (at 212.725 138.43 0)
       (effects (font (size 1.27 1.27)) (justify left) hide)
     )
     (property "DNP" "0" (at 212.725 138.43 0)

Kicad/dac4.kicad_sch

@@ -232,7 +232,7 @@
     (uuid f96146e0-d3b5-4ca2-be41-6ec641aada57)
   )
 
-  (text "This is a 4-bit R2R DAC.\n\nThe maximum output is 15/16 of the input: 3.3V * 15 / 16 = 3.09375 V\n\nWe want 700 mV into the RGB buffer.\n\nBuffer Input = 700 mV = 3.09375 V * R / (1000 + R)\n\n=> 3.09375 V * R = 700 mV * (1000 + R)\n=> ( 3.09375 V - 700mV ) * R = 700 mV * 1000\n=> R = 292 Ohm\n\nThe Buffer Input Impedance is 800k, which we can ignore.\n\n300 Ohm is a close standard value.\n\nDIGITAL_IN[0] is the least significant bit\nDIGITAL_IN[3] is the most significant bit\n\nEach resistor must be better than 1/32 or 3.1%.\n"
+  (text "This is a 4-bit R2R DAC.\n\nThe maximum output is 15/16 of the input: 3.3V * 15 / 16 = 3.09375 V\n\nWe want 700 mV into the RGB buffer.\n\nBuffer Input = 700 mV = 3.09375 V * R / (2000 + R)\n\n=> 3.09375 V * R = 700 mV * (2000 + R)\n=> ( 3.09375 V - 700mV ) * R = 700 mV * 2000\n=> R = 585 Ohm\n\nThe Buffer Input Impedance is 800k, which we can ignore.\n\n560 Ohm is a close standard value on the JLCPCB basic 0805 resistor list.\nIt drops the voltage to 676mV.\n\nDIGITAL_IN[0] is the least significant bit\nDIGITAL_IN[3] is the most significant bit\n\nEach resistor must be better than 1/32 or 3.1%.\n"
     (at 24.765 160.02 0)
     (effects (font (size 1.27 1.27)) (justify left bottom))
     (uuid 6c4c1fdc-b478-48e2-8f9b-2b33528032ce)
@@ -687,7 +687,7 @@
     (property "Reference" "R510" (at 193.548 82.6516 0)
       (effects (font (size 1.27 1.27)) (justify left))
     )
-    (property "Value" "300" (at 193.548 84.963 0)
+    (property "Value" "560" (at 193.548 84.963 0)
       (effects (font (size 1.27 1.27)) (justify left))
     )
     (property "Footprint" "Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder" (at 189.992 83.82 90)
@@ -702,13 +702,13 @@
     (property "Digikey" "~" (at 191.77 83.82 0)
       (effects (font (size 1.27 1.27)) hide)
     )
-    (property "MPN" "0805W8F3000T5E" (at 191.77 83.82 0)
+    (property "MPN" "0805W8F5600T5E" (at 191.77 83.82 0)
       (effects (font (size 1.27 1.27)) hide)
     )
     (property "Manufacturer" "Uniroyal" (at 191.77 83.82 0)
       (effects (font (size 1.27 1.27)) hide)
     )
-    (property "LCSC Part#" "C17617" (at 191.77 83.82 0)
+    (property "LCSC Part#" "C28636" (at 191.77 83.82 0)
       (effects (font (size 1.27 1.27)) hide)
     )
     (property "Tolerance" "1%" (at 191.77 83.82 0)

Kicad/expansion_slots.kicad_sch

@@ -739,8 +739,8 @@
   )
 
   (no_connect (at 248.92 38.735) (uuid 02d67f1f-aacb-4a18-92e9-d8a76ca1a93a))
-  (no_connect (at 248.92 53.975) (uuid 0467e938-285a-41e8-9600-255711709720))
   (no_connect (at 172.72 43.815) (uuid 26708d4e-117c-4959-88df-d24855941685))
+  (no_connect (at 244.475 53.975) (uuid 6495731f-db63-45b3-b4fd-27a4b4628d54))
   (no_connect (at 248.92 41.275) (uuid defe4d4f-f782-4071-aed2-81fe0c120fa5))
 
   (bus_entry (at 33.02 46.99) (size 2.54 2.54)
@@ -1818,6 +1818,10 @@
     (stroke (width 0) (type default))
     (uuid d355e91f-2f69-4e1e-a17c-f480e8ce5295)
   )
+  (wire (pts (xy 244.475 53.975) (xy 248.92 53.975))
+    (stroke (width 0) (type default))
+    (uuid d3cd7a09-3652-4db3-8f74-11def4394100)
+  )
   (wire (pts (xy 267.97 85.725) (xy 267.97 81.915))
     (stroke (width 0) (type default))
     (uuid d55ae862-019e-4c01-a8d1-2d1825d17b0b)