diff --git a/library/transistors.dcm b/library/transistors.dcm
index 27aa1e17..8d506f5c 100644
--- a/library/transistors.dcm
+++ b/library/transistors.dcm
@@ -1188,6 +1188,18 @@ K N-Channel MOSFET
 F http://www.fairchildsemi.com/ds/BS/BS170.pdf
 $ENDCMP
 #
+$CMP MMBT3904
+D MMBT3904, 40V Vce, 0.2A Ic, NPN, Small Signal Transistor,SOT23
+K MMBT3904 NPN Transistor
+F http://www.nxp.com/documents/data_sheet/MMBT3904.pdf
+$ENDCMP
+#
+$CMP MMBT3906
+D MMBT3906, 40V Vce, 0.2A Ic, PNP, Small Signal Transistor, SOT23
+K MMBT3904 PNP Transistor
+F http://www.nxp.com/documents/data_sheet/MMBT3906.pdf
+$ENDCMP
+#
 $CMP MOSN-SO8
 D SI4456DY - SO8
 $ENDCMP
diff --git a/library/transistors.lib b/library/transistors.lib
index 938ced47..5363762e 100644
--- a/library/transistors.lib
+++ b/library/transistors.lib
@@ -4673,6 +4673,52 @@ X D 3 100 200 100 D 40 40 1 1 P
 ENDDRAW
 ENDDEF
 #
+# MMBT3904
+#
+DEF MMBT3904 Q 0 0 Y Y 1 F N
+F0 "Q" 0 -150 50 H V R CNN
+F1 "MMBT3904" 0 150 50 H V R CNN
+F2 "" 0 0 60 H V C CNN
+F3 "" 0 0 60 H V C CNN
+$FPLIST
+ SOT23
+$ENDFPLIST
+DRAW
+C 50 0 111 0 1 10 N
+P 2 0 1 0  0 0  100 100 N
+P 3 0 1 10  0 75  0 -75  0 -75 N
+P 3 0 1 0  50 -50  0 0  0 0 N
+P 3 0 1 0  90 -90  100 -100  100 -100 N
+P 5 0 1 0  90 -90  70 -30  30 -70  90 -90  90 -90 F
+X B 1 -200 0 200 R 40 40 1 1 I
+X E 2 100 -200 100 U 40 40 1 1 P
+X C 3 100 200 100 D 40 40 1 1 P
+ENDDRAW
+ENDDEF
+#
+# MMBT3906
+#
+DEF MMBT3906 Q 0 0 Y Y 1 F N
+F0 "Q" 0 -150 50 H V R CNN
+F1 "MMBT3906" 0 150 50 H V R CNN
+F2 "" 0 0 60 H V C CNN
+F3 "" 0 0 60 H V C CNN
+$FPLIST
+ SOT23
+$ENDFPLIST
+DRAW
+C 50 0 111 0 1 10 N
+P 2 0 1 0  0 0  100 100 N
+P 3 0 1 10  0 75  0 -75  0 -75 F
+P 3 0 1 0  25 -25  0 0  0 0 N
+P 3 0 1 0  100 -100  65 -65  65 -65 N
+P 5 0 1 0  25 -25  50 -75  75 -50  25 -25  25 -25 F
+X B 1 -200 0 200 R 40 40 1 1 I
+X E 2 100 -200 100 U 40 40 1 1 P
+X C 3 100 200 100 D 40 40 1 1 P
+ENDDRAW
+ENDDEF
+#
 # MOSN-SO8
 #
 DEF MOSN-SO8 Q 0 0 Y Y 1 F N