diff --git a/electropepper_kicad.bak b/electropepper_kicad.bak
index b55a9ec..a02aa09 100644
--- a/electropepper_kicad.bak
+++ b/electropepper_kicad.bak
@@ -128,10 +128,13 @@ ENDDEF
 # MIC4680
 #
 DEF MIC4680 U 0 40 Y Y 1 F N
-F0 "U" -350 350 60 H V C CNN
-F1 "MIC4680" 400 -350 60 H V C CNN
+F0 "U" -350 350 50 H V C CNN
+F1 "MIC4680" 350 -350 50 H V C CNN
 F2 "" 0 0 60 H I C CNN
 F3 "" 0 0 60 H I C CNN
+$FPLIST
+ SOIC-8
+$ENDFPLIST
 DRAW
 S 400 -300 -400 300 0 1 0 f
 X SHDN 1 -550 -100 150 R 40 40 1 1 I
@@ -145,6 +148,47 @@ X FB ~ 550 -100 150 L 40 40 1 1 I
 ENDDRAW
 ENDDEF
 #
+# SN75172
+#
+DEF SN75172 U 0 20 Y Y 4 F N
+F0 "U" -150 200 47 H V C CNN
+F1 "SN75172" 200 -200 47 H V C CNN
+F2 "" 0 -50 47 H I C CNN
+F3 "" 0 -50 47 H I C CNN
+$FPLIST
+ SOIC-20
+$ENDFPLIST
+DRAW
+T 0 40 110 20 0 0 0 "g/~g" Normal 0 C C
+C 110 -30 10 0 1 0 N
+S -200 150 200 -150 0 1 0 f
+P 2 0 1 0 0 0 -100 0 N
+P 2 0 1 0 40 30 40 80 N
+P 2 0 1 0 100 25 150 25 N
+P 2 0 1 0 100 50 100 -50 N
+P 2 0 1 0 120 -30 150 -30 N
+P 2 0 1 0 150 -30 200 -100 N
+P 2 0 1 0 150 25 200 100 N
+P 4 0 1 0 0 50 100 0 0 -50 0 50 N
+X 1A 1 -350 0 150 R 40 40 1 1 B
+X 1Y 2 350 100 150 L 40 40 1 1 B
+X 1Z 4 350 -100 150 L 40 40 1 1 B
+X G 5 -350 -100 150 R 40 40 1 1 B
+X GND 10 0 -300 150 U 40 20 1 1 B
+X VCC 20 0 300 150 D 40 20 1 1 W
+X ~G 15 -350 100 150 R 40 40 1 1 B
+X 2Z 6 350 -100 150 L 40 40 2 1 B
+X 2Y 8 350 100 150 L 40 40 2 1 B
+X 2A 9 -350 0 150 R 40 40 2 1 B
+X 3A 11 -350 0 150 R 40 40 3 1 B
+X 3Y 12 350 100 150 L 40 40 3 1 B
+X 3Z 14 350 -100 150 L 40 40 3 1 B
+X 4Z 16 350 -100 150 L 40 40 4 1 B
+X 4Y 18 350 100 150 L 40 40 4 1 B
+X 4A 19 -350 0 150 R 40 40 4 1 B
+ENDDRAW
+ENDDEF
+#
 # TPS62046
 #
 DEF TPS62046 U 0 40 Y Y 1 F N
diff --git a/electropepper_kicad.bck b/electropepper_kicad.bck
index d9a7e75..afeb932 100644
--- a/electropepper_kicad.bck
+++ b/electropepper_kicad.bck
@@ -6,4 +6,16 @@ K Generic LCD 16x2 Alphanumeric 16pin Green Backlight
 F http://www.kamami.pl/dl/wc1602a0.pdf
 $ENDCMP
 #
+$CMP MIC4680
+D MIC4680 1A 200kHz SuperSwitcher Buck Regulator
+K DC/DC converter
+F /home/ricardo/Downloads/IC datasheets/MIC4680.pdf
+$ENDCMP
+#
+$CMP SN75172
+D QUADRUPLE DIFFRENTIAL LINE DRIVER
+K RS422/RS485
+F /home/ricardo/Downloads/IC datasheets/sn75172.pdf
+$ENDCMP
+#
 #End Doc Library
diff --git a/electropepper_kicad.dcm b/electropepper_kicad.dcm
index 04bb3bb..afeb932 100644
--- a/electropepper_kicad.dcm
+++ b/electropepper_kicad.dcm
@@ -12,4 +12,10 @@ K DC/DC converter
 F /home/ricardo/Downloads/IC datasheets/MIC4680.pdf
 $ENDCMP
 #
+$CMP SN75172
+D QUADRUPLE DIFFRENTIAL LINE DRIVER
+K RS422/RS485
+F /home/ricardo/Downloads/IC datasheets/sn75172.pdf
+$ENDCMP
+#
 #End Doc Library
diff --git a/electropepper_kicad.lib b/electropepper_kicad.lib
index 7a157bc..5476eb4 100644
--- a/electropepper_kicad.lib
+++ b/electropepper_kicad.lib
@@ -148,6 +148,47 @@ X FB ~ 550 -100 150 L 40 40 1 1 I
 ENDDRAW
 ENDDEF
 #
+# SN75172
+#
+DEF SN75172 U 0 20 Y Y 4 F N
+F0 "U" -150 200 47 H V C CNN
+F1 "SN75172" 200 -200 47 H V C CNN
+F2 "" 0 -50 47 H I C CNN
+F3 "" 0 -50 47 H I C CNN
+$FPLIST
+ SOIC-20
+$ENDFPLIST
+DRAW
+T 0 40 110 20 0 0 0 "g|~g" Normal 0 C C
+C 110 -30 10 0 1 0 N
+S -200 150 200 -150 0 1 0 f
+P 2 0 1 0 0 0 -100 0 N
+P 2 0 1 0 40 30 40 80 N
+P 2 0 1 0 100 25 150 25 N
+P 2 0 1 0 100 50 100 -50 N
+P 2 0 1 0 120 -30 150 -30 N
+P 2 0 1 0 150 -30 200 -100 N
+P 2 0 1 0 150 25 200 100 N
+P 4 0 1 0 0 50 100 0 0 -50 0 50 N
+X 1A 1 -350 0 150 R 40 40 1 1 B
+X 1Y 2 350 100 150 L 40 40 1 1 B
+X 1Z 4 350 -100 150 L 40 40 1 1 B
+X G 5 -350 -100 150 R 40 40 1 1 B
+X GND 10 0 -300 150 U 40 20 1 1 B
+X VCC 20 0 300 150 D 40 20 1 1 W
+X ~G 15 -350 100 150 R 40 40 1 1 B
+X 2Z 6 350 -100 150 L 40 40 2 1 B
+X 2Y 8 350 100 150 L 40 40 2 1 B
+X 2A 9 -350 0 150 R 40 40 2 1 B
+X 3A 11 -350 0 150 R 40 40 3 1 B
+X 3Y 12 350 100 150 L 40 40 3 1 B
+X 3Z 14 350 -100 150 L 40 40 3 1 B
+X 4Z 16 350 -100 150 L 40 40 4 1 B
+X 4Y 18 350 100 150 L 40 40 4 1 B
+X 4A 19 -350 0 150 R 40 40 4 1 B
+ENDDRAW
+ENDDEF
+#
 # TPS62046
 #
 DEF TPS62046 U 0 40 Y Y 1 F N