MIDI_IO.sch

EESchema Schematic File Version 4
EELAYER 30 0
EELAYER END
$Descr User 7362 4331
encoding utf-8
Sheet 1 1
Title "MIDI I/O circuit"
Date "2020-08-26"
Rev "0.8"
Comp "6r1d"
Comment1 "**Currently untested**"
Comment2 "Based on a circuit by Notes and Volts and MIDI DIN electrical specification"
Comment3 "By picking the right parts you can use this circuit with both 5V and 3.3V MCUs"
Comment4 ""
$EndDescr
$Comp
L power:+5V #PWR04
U 1 1 5F49ADEA
P 2900 1100
F 0 "#PWR04" H 2900 950 50  0001 C CNN
F 1 "+5V" V 2915 1228 50  0000 L CNN
F 2 "" H 2900 1100 50  0001 C CNN
F 3 "" H 2900 1100 50  0001 C CNN
	1    2900 1100
	0    1    1    0   
$EndComp
$Comp
L Device:R_US R2
U 1 1 5F49B7A9
P 2700 1100
F 0 "R2" V 2600 1100 50  0000 C CNN
F 1 "220" V 2800 1100 50  0000 C CNN
F 2 "Resistor_SMD:R_0603_1608Metric" V 2740 1090 50  0001 C CNN
F 3 "~" H 2700 1100 50  0001 C CNN
	1    2700 1100
	0    1    1    0   
$EndComp
Wire Wire Line
	2100 1100 2150 1100
Wire Wire Line
	2850 1100 2900 1100
$Comp
L power:GND #PWR05
U 1 1 5F49E9A1
P 1800 1350
F 0 "#PWR05" H 1800 1100 50  0001 C CNN
F 1 "GND" H 1805 1177 50  0000 C CNN
F 2 "" H 1800 1350 50  0001 C CNN
F 3 "" H 1800 1350 50  0001 C CNN
	1    1800 1350
	1    0    0    -1  
$EndComp
Wire Wire Line
	1800 1300 1800 1350
Text GLabel 750  1100 0    50   Input ~ 0
TX
Wire Wire Line
	1450 1100 1500 1100
Text Notes 600  2400 0    50   ~ 0
Output circuit
$Comp
L Device:Ferrite_Bead FB1
U 1 1 5F4D0281
P 1300 1100
F 0 "FB1" V 1150 1100 50  0000 C CNN
F 1 "1k 100mHz" V 1450 1100 50  0000 C CNN
F 2 "Inductor_SMD:L_0603_1608Metric" V 1230 1100 50  0001 C CNN
F 3 "~" H 1300 1100 50  0001 C CNN
	1    1300 1100
	0    1    1    0   
$EndComp
Text Notes 3450 2400 0    50   ~ 0
Input circuit
Wire Wire Line
	3500 1100 3550 1100
Wire Wire Line
	5850 900  6000 900 
Connection ~ 6000 900 
Wire Wire Line
	5700 1450 6000 1450
Wire Wire Line
	6000 1450 6050 1450
Connection ~ 6000 1450
Text GLabel 6050 1450 2    50   Input ~ 0
RX
Wire Wire Line
	6000 850  6000 900 
Wire Wire Line
	5750 1550 5750 2100
Wire Wire Line
	5700 1550 5750 1550
$Comp
L power:GND #PWR02
U 1 1 5F441C3F
P 5900 2100
F 0 "#PWR02" H 5900 1850 50  0001 C CNN
F 1 "GND" V 5900 1900 50  0000 C CNN
F 2 "" H 5900 2100 50  0001 C CNN
F 3 "" H 5900 2100 50  0001 C CNN
	1    5900 2100
	1    0    0    -1  
$EndComp
Wire Wire Line
	5900 1250 5900 1650
Wire Wire Line
	5700 1250 5900 1250
Wire Wire Line
	5700 1150 5850 1150
Wire Wire Line
	6000 900  6000 1000
Wire Wire Line
	5850 1150 5850 900 
Wire Wire Line
	6000 1450 6000 1300
$Comp
L power:+5V #PWR03
U 1 1 5F43A118
P 6000 850
F 0 "#PWR03" H 6000 700 50  0001 C CNN
F 1 "+5V" H 6015 1023 50  0000 C CNN
F 2 "" H 6000 850 50  0001 C CNN
F 3 "" H 6000 850 50  0001 C CNN
	1    6000 850 
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR01
U 1 1 5F439DC8
P 5750 2100
F 0 "#PWR01" H 5750 1850 50  0001 C CNN
F 1 "GND" V 5750 1900 50  0000 C CNN
F 2 "" H 5750 2100 50  0001 C CNN
F 3 "" H 5750 2100 50  0001 C CNN
	1    5750 2100
	1    0    0    -1  
$EndComp
$Comp
L Device:R_US R5
U 1 1 5F433A78
P 5900 1800
F 0 "R5" V 5800 1750 50  0000 L CNN
F 1 "4.7k" V 6000 1700 50  0000 L CNN
F 2 "Resistor_SMD:R_0603_1608Metric" V 5940 1790 50  0001 C CNN
F 3 "~" H 5900 1800 50  0001 C CNN
	1    5900 1800
	1    0    0    -1  
$EndComp
$Comp
L Device:R_US R4
U 1 1 5F43376F
P 6000 1150
F 0 "R4" V 5900 1100 50  0000 L CNN
F 1 "220" V 6100 1100 50  0000 L CNN
F 2 "Resistor_SMD:R_0603_1608Metric" V 6040 1140 50  0001 C CNN
F 3 "~" H 6000 1150 50  0001 C CNN
	1    6000 1150
	1    0    0    -1  
$EndComp
$Comp
L Isolator:6N138 U1
U 1 1 5F43292B
P 5400 1350
F 0 "U1" H 5400 1817 50  0000 C CNN
F 1 "6N138" H 5400 1726 50  0000 C CNN
F 2 "Package_DIP:DIP-8_W7.62mm" H 5690 1050 50  0001 C CNN
F 3 "http://www.onsemi.com/pub/Collateral/HCPL2731-D.pdf" H 5690 1050 50  0001 C CNN
	1    5400 1350
	1    0    0    -1  
$EndComp
$Comp
L Diode:1N914 D1
U 1 1 5F431E0C
P 4900 1300
F 0 "D1" V 4900 1150 50  0000 L CNN
F 1 "1N914" H 4800 1400 50  0000 L CNN
F 2 "Diode_SMD:D_1206_3216Metric_Pad1.42x1.75mm_HandSolder" H 4900 1125 50  0001 C CNN
F 3 "http://www.vishay.com/docs/85622/1n914.pdf" H 4900 1300 50  0001 C CNN
	1    4900 1300
	0    1    1    0   
$EndComp
$Comp
L Device:R_US R3
U 1 1 5F431879
P 4700 1100
F 0 "R3" V 4600 1100 50  0000 C CNN
F 1 "220" V 4800 1100 50  0000 C CNN
F 2 "Resistor_SMD:R_0603_1608Metric" V 4740 1090 50  0001 C CNN
F 3 "~" H 4700 1100 50  0001 C CNN
	1    4700 1100
	0    1    1    0   
$EndComp
Wire Wire Line
	2450 1100 2550 1100
$Comp
L Device:Ferrite_Bead FB2
U 1 1 5F4FFCFE
P 2300 1100
F 0 "FB2" V 2150 1100 50  0000 C CNN
F 1 "1k 100mHz" V 2450 1100 50  0000 C CNN
F 2 "Inductor_SMD:L_0603_1608Metric" V 2230 1100 50  0001 C CNN
F 3 "~" H 2300 1100 50  0001 C CNN
	1    2300 1100
	0    1    1    0   
$EndComp
$Comp
L Device:R_US R1
U 1 1 5F5000D0
P 950 1100
F 0 "R1" V 850 1100 50  0000 C CNN
F 1 "220" V 1050 1100 50  0000 C CNN
F 2 "Resistor_SMD:R_0603_1608Metric" V 990 1090 50  0001 C CNN
F 3 "~" H 950 1100 50  0001 C CNN
	1    950  1100
	0    1    1    0   
$EndComp
Wire Wire Line
	1100 1100 1150 1100
Wire Wire Line
	750  1100 800  1100
Wire Notes Line
	550  550  3250 550 
Wire Notes Line
	550  550  550  2450
Wire Notes Line
	550  2450 3250 2450
Wire Notes Line
	3250 2450 3250 550 
$Comp
L Device:Ferrite_Bead FB3
U 1 1 5F543F15
P 4350 1100
F 0 "FB3" V 4200 1100 50  0000 C CNN
F 1 "1k 100mHz" V 4500 1100 50  0000 C CNN
F 2 "Inductor_SMD:L_0603_1608Metric" V 4280 1100 50  0001 C CNN
F 3 "~" H 4350 1100 50  0001 C CNN
	1    4350 1100
	0    1    1    0   
$EndComp
Wire Wire Line
	4500 1100 4550 1100
Wire Wire Line
	4150 1100 4200 1100
$Comp
L Device:Ferrite_Bead FB4
U 1 1 5F55D3AA
P 4350 1600
F 0 "FB4" V 4200 1600 50  0000 C CNN
F 1 "1k 100mHz" V 4500 1600 50  0000 C CNN
F 2 "Inductor_SMD:L_0603_1608Metric" V 4280 1600 50  0001 C CNN
F 3 "~" H 4350 1600 50  0001 C CNN
	1    4350 1600
	0    1    1    0   
$EndComp
NoConn ~ 1500 1000
NoConn ~ 2100 1000
$Comp
L power:GND #PWR0101
U 1 1 5F591762
P 4500 2150
F 0 "#PWR0101" H 4500 1900 50  0001 C CNN
F 1 "GND" V 4500 1950 50  0000 C CNN
F 2 "" H 4500 2150 50  0001 C CNN
F 3 "" H 4500 2150 50  0001 C CNN
	1    4500 2150
	0    -1   -1   0   
$EndComp
Wire Wire Line
	5900 1950 5900 2100
Wire Wire Line
	5100 1100 5100 1250
NoConn ~ 4150 1000
NoConn ~ 3550 1000
Wire Wire Line
	4850 1100 4900 1100
Wire Wire Line
	4900 1150 4900 1100
Connection ~ 4900 1100
Wire Wire Line
	4900 1100 5100 1100
Wire Wire Line
	4500 1600 4900 1600
Connection ~ 4900 1600
Wire Wire Line
	4900 1600 5100 1600
Wire Notes Line
	6250 2450 6250 550 
Wire Notes Line
	6250 550  3400 550 
Wire Notes Line
	3400 2450 6250 2450
Wire Wire Line
	3500 1100 3500 1600
Wire Wire Line
	3850 1300 3850 1350
Wire Wire Line
	4900 1450 4900 1600
Wire Wire Line
	5100 1450 5100 1600
Wire Notes Line
	3400 2450 3400 550 
$Comp
L Connector_Generic:Conn_01x04 J1
U 1 1 5F4756C5
P 750 3100
F 0 "J1" H 668 2675 50  0000 C CNN
F 1 "Conn_01x04" H 668 2766 50  0000 C CNN
F 2 "Connector_Molex:Molex_KK-254_AE-6410-04A_1x04_P2.54mm_Vertical" H 750 3100 50  0001 C CNN
F 3 "~" H 750 3100 50  0001 C CNN
	1    750  3100
	-1   0    0    1   
$EndComp
Wire Wire Line
	950  3200 1000 3200
Wire Wire Line
	950  3100 1000 3100
Text GLabel 1000 3000 2    50   Input ~ 0
TX
Text GLabel 1000 2900 2    50   Input ~ 0
RX
Wire Wire Line
	950  3000 1000 3000
Wire Wire Line
	950  2900 1000 2900
$Comp
L Mechanical:MountingHole_Pad H1
U 1 1 5F48178A
P 1850 2900
F 0 "H1" H 1800 3100 50  0000 L CNN
F 1 "MountingHole_Pad" H 1950 2858 50  0001 L CNN
F 2 "MountingHole:MountingHole_2mm" H 1850 2900 50  0001 C CNN
F 3 "~" H 1850 2900 50  0001 C CNN
	1    1850 2900
	1    0    0    -1  
$EndComp
$Comp
L Mechanical:MountingHole_Pad H2
U 1 1 5F4823C3
P 2050 2900
F 0 "H2" H 2000 3100 50  0000 L CNN
F 1 "MountingHole_Pad" H 2150 2858 50  0001 L CNN
F 2 "MountingHole:MountingHole_2mm" H 2050 2900 50  0001 C CNN
F 3 "~" H 2050 2900 50  0001 C CNN
	1    2050 2900
	1    0    0    -1  
$EndComp
$Comp
L Mechanical:MountingHole_Pad H4
U 1 1 5F482751
P 2450 2900
F 0 "H4" H 2400 3100 50  0000 L CNN
F 1 "MountingHole_Pad" H 2550 2858 50  0001 L CNN
F 2 "MountingHole:MountingHole_2mm" H 2450 2900 50  0001 C CNN
F 3 "~" H 2450 2900 50  0001 C CNN
	1    2450 2900
	1    0    0    -1  
$EndComp
$Comp
L Mechanical:MountingHole_Pad H3
U 1 1 5F482A2F
P 2250 2900
F 0 "H3" H 2200 3100 50  0000 L CNN
F 1 "MountingHole_Pad" H 2350 2858 50  0001 L CNN
F 2 "MountingHole:MountingHole_2mm" H 2250 2900 50  0001 C CNN
F 3 "~" H 2250 2900 50  0001 C CNN
	1    2250 2900
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR0104
U 1 1 5F485072
P 1850 3000
F 0 "#PWR0104" H 1850 2750 50  0001 C CNN
F 1 "GND" V 1850 2800 50  0000 C CNN
F 2 "" H 1850 3000 50  0001 C CNN
F 3 "" H 1850 3000 50  0001 C CNN
	1    1850 3000
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR0105
U 1 1 5F485ED6
P 2050 3000
F 0 "#PWR0105" H 2050 2750 50  0001 C CNN
F 1 "GND" V 2050 2800 50  0000 C CNN
F 2 "" H 2050 3000 50  0001 C CNN
F 3 "" H 2050 3000 50  0001 C CNN
	1    2050 3000
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR0106
U 1 1 5F486247
P 2250 3000
F 0 "#PWR0106" H 2250 2750 50  0001 C CNN
F 1 "GND" V 2250 2800 50  0000 C CNN
F 2 "" H 2250 3000 50  0001 C CNN
F 3 "" H 2250 3000 50  0001 C CNN
	1    2250 3000
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR0107
U 1 1 5F486E1F
P 2450 3000
F 0 "#PWR0107" H 2450 2750 50  0001 C CNN
F 1 "GND" V 2450 2800 50  0000 C CNN
F 2 "" H 2450 3000 50  0001 C CNN
F 3 "" H 2450 3000 50  0001 C CNN
	1    2450 3000
	1    0    0    -1  
$EndComp
Text Notes 600  3450 0    50   ~ 0
Inputs with inverse\npolarity protection
Wire Notes Line
	550  3500 550  2600
Wire Notes Line
	1650 2600 1650 3500
Wire Notes Line
	1750 2600 1750 3500
Wire Notes Line
	1750 3500 2550 3500
Wire Notes Line
	2550 3500 2550 2600
Wire Notes Line
	2550 2600 1750 2600
Text Notes 1800 3450 0    50   ~ 0
Mount holes
Wire Notes Line
	550  2600 1650 2600
Wire Notes Line
	550  3500 1650 3500
$Comp
L din-5_180degree_jack_shield:DIN-5_180degree_JS J_OUT_1
U 1 1 5F5B7320
P 1800 1000
F 0 "J_OUT_1" H 1800 900 50  0000 C CNN
F 1 "DIN-5_180degree_JS" H 1800 724 50  0001 C CNN
F 2 "MIDI_IO:din-5-shielded" H 1800 1000 50  0001 C CNN
F 3 "http://www.mouser.com/ds/2/18/40_c091_abd_e-75918.pdf" H 1800 1000 50  0001 C CNN
	1    1800 1000
	-1   0    0    1   
$EndComp
$Comp
L power:GND #PWR0108
U 1 1 5F5C436C
P 1500 850
F 0 "#PWR0108" H 1500 600 50  0001 C CNN
F 1 "GND" V 1505 722 50  0000 R CNN
F 2 "" H 1500 850 50  0001 C CNN
F 3 "" H 1500 850 50  0001 C CNN
	1    1500 850 
	0    1    1    0   
$EndComp
Wire Wire Line
	1500 850  1550 850 
$Comp
L din-5_180degree_jack_shield:DIN-5_180degree_JS J_IN_1
U 1 1 5F5CEF14
P 3850 1000
F 0 "J_IN_1" H 3850 900 50  0000 C CNN
F 1 "DIN-5_180degree_JS" H 3850 724 50  0001 C CNN
F 2 "MIDI_IO:din-5-shielded" H 3850 1000 50  0001 C CNN
F 3 "http://www.mouser.com/ds/2/18/40_c091_abd_e-75918.pdf" H 3850 1000 50  0001 C CNN
	1    3850 1000
	-1   0    0    1   
$EndComp
$Comp
L Device:C C2
U 1 1 5F5ED2DD
P 4200 1950
F 0 "C2" V 4250 2050 50  0000 L CNN
F 1 "0.1uF" V 4250 1650 50  0000 L CNN
F 2 "Capacitor_SMD:C_0603_1608Metric" H 4238 1800 50  0001 C CNN
F 3 "~" H 4200 1950 50  0001 C CNN
	1    4200 1950
	0    -1   -1   0   
$EndComp
$Comp
L power:GND #PWR0109
U 1 1 5F601BA9
P 4500 1950
F 0 "#PWR0109" H 4500 1700 50  0001 C CNN
F 1 "GND" V 4500 1750 50  0000 C CNN
F 2 "" H 4500 1950 50  0001 C CNN
F 3 "" H 4500 1950 50  0001 C CNN
	1    4500 1950
	0    -1   -1   0   
$EndComp
Wire Wire Line
	4350 1950 4500 1950
Wire Wire Line
	3600 850  3500 850 
Wire Wire Line
	3500 850  3500 700 
Wire Wire Line
	3500 700  3550 700 
Text GLabel 3550 700  2    50   Input ~ 0
IN_SH_OUT
Text GLabel 3900 1350 2    50   Input ~ 0
IN_SH
Text GLabel 3950 2150 0    50   Input ~ 0
IN_SH
Text GLabel 3950 1950 0    50   Input ~ 0
IN_SH_OUT
Wire Wire Line
	3950 1950 4050 1950
Wire Wire Line
	3750 2150 4050 2150
Wire Wire Line
	3850 1350 3900 1350
Wire Wire Line
	4350 2150 4500 2150
$Comp
L Device:C C1
U 1 1 5F5630B6
P 4200 2150
F 0 "C1" V 4250 2250 50  0000 L CNN
F 1 "0.1uF" V 4250 1850 50  0000 L CNN
F 2 "Capacitor_SMD:C_0603_1608Metric" H 4238 2000 50  0001 C CNN
F 3 "~" H 4200 2150 50  0001 C CNN
	1    4200 2150
	0    -1   -1   0   
$EndComp
Wire Wire Line
	4200 1600 3500 1600
Wire Wire Line
	1300 3100 1350 3100
$Comp
L power:GND #PWR0102
U 1 1 5F476304
P 1350 3100
F 0 "#PWR0102" H 1350 2850 50  0001 C CNN
F 1 "GND" V 1355 2972 50  0000 R CNN
F 2 "" H 1350 3100 50  0001 C CNN
F 3 "" H 1350 3100 50  0001 C CNN
	1    1350 3100
	0    -1   -1   0   
$EndComp
Wire Wire Line
	1300 3200 1350 3200
$Comp
L Device:D D3
U 1 1 5F4686D0
P 1150 3100
F 0 "D3" H 1250 3150 50  0000 C CNN
F 1 "D" H 1150 2974 50  0001 C CNN
F 2 "Diode_SMD:D_0603_1608Metric" H 1150 3100 50  0001 C CNN
F 3 "~" H 1150 3100 50  0001 C CNN
	1    1150 3100
	1    0    0    -1  
$EndComp
$Comp
L Device:D D2
U 1 1 5F4682EC
P 1150 3200
F 0 "D2" H 1050 3150 50  0000 C CNN
F 1 "D" H 1150 3074 50  0001 C CNN
F 2 "Diode_SMD:D_0603_1608Metric" H 1150 3200 50  0001 C CNN
F 3 "~" H 1150 3200 50  0001 C CNN
	1    1150 3200
	-1   0    0    1   
$EndComp
$Comp
L power:+5V #PWR0103
U 1 1 5F476FA5
P 1350 3200
F 0 "#PWR0103" H 1350 3050 50  0001 C CNN
F 1 "+5V" V 1365 3328 50  0000 L CNN
F 2 "" H 1350 3200 50  0001 C CNN
F 3 "" H 1350 3200 50  0001 C CNN
	1    1350 3200
	0    1    1    0   
$EndComp
Text Notes 600  2250 0    50   ~ 0
R1 = R_C in MIDI spec;\nit's 220Ω for 5V and 33Ω for 3.3V.\nR2 = R_A in MIDI spec;\nit's 220Ω for 5V and 10Ω for 3.3V.
$EndSCHEMATC