EESchema Schematic File Version 4
EELAYER 30 0
EELAYER END
$Descr A4 11693 8268
encoding utf-8
Sheet 5 6
Title ""
Date ""
Rev ""
Comp ""
Comment1 ""
Comment2 ""
Comment3 ""
Comment4 ""
$EndDescr
Wire Wire Line
	5350 4250 5250 4250
Wire Wire Line
	4550 4150 4550 4050
Wire Wire Line
	7250 3950 7250 4150
Wire Wire Line
	7550 3650 7550 4150
Wire Wire Line
	6550 4250 6850 4250
Text Label 6850 4250 2    70   ~ 0
GAIN
$Comp
L Analog_DAC:AUDIOAMP_MAX98357 U5
U 1 1 60FE0C5F
P 5950 3950
F 0 "U5" H 6150 4600 42  0000 L BNN
F 1 "MAX98357A" H 5450 3250 42  0000 L BNN
F 2 "Package_DFN_QFN:QFN-16-1EP_3x3mm_P0.5mm_EP1.7x1.7mm_ThermalVias" H 5950 3950 50  0001 C CNN
F 3 "" H 5950 3950 50  0001 C CNN
	1    5950 3950
	1    0    0    -1  
$EndComp
Text Notes 5450 3050 0    59   ~ 0
R1 Channel Selection:\nLEFT = VDD (0 Ohm)\nRIGHT = 370K (94*VDD-100)\nLEFT/2 + RIGHT/2 = 1.011M (222.2*VDD-100)
Text Notes 6850 3350 0    59   ~ 0
ToDo: Ferrite (select w/high Z at high F,\nlow Z at low F). Try to block everything\n>1MHz or so.
Text Notes 6550 4350 0    59   ~ 0
Gain=9dB
Text Label 3300 3850 0    70   ~ 0
GAIN
$Comp
L Device:R R27
U 1 1 60FE0C75
P 3150 3550
F 0 "R27" H 3220 3596 50  0000 L CNN
F 1 "10K" H 3220 3505 50  0000 L CNN
F 2 "Resistor_SMD:R_0402_1005Metric" V 3080 3550 50  0001 C CNN
F 3 "~" H 3150 3550 50  0001 C CNN
	1    3150 3550
	1    0    0    -1  
$EndComp
$Comp
L Device:R R28
U 1 1 60FE0C7B
P 3150 4100
F 0 "R28" H 3220 4146 50  0000 L CNN
F 1 "10K" H 3220 4055 50  0000 L CNN
F 2 "Resistor_SMD:R_0402_1005Metric" V 3080 4100 50  0001 C CNN
F 3 "~" H 3150 4100 50  0001 C CNN
	1    3150 4100
	1    0    0    -1  
$EndComp
Wire Wire Line
	3150 3700 3150 3850
Wire Wire Line
	3300 3850 3150 3850
Connection ~ 3150 3850
Wire Wire Line
	3150 3850 3150 3950
$Comp
L power:+3V3 #PWR0149
U 1 1 60FE0C85
P 3150 3250
F 0 "#PWR0149" H 3150 3100 50  0001 C CNN
F 1 "+3V3" H 3165 3423 50  0000 C CNN
F 2 "" H 3150 3250 50  0001 C CNN
F 3 "" H 3150 3250 50  0001 C CNN
	1    3150 3250
	1    0    0    -1  
$EndComp
Wire Wire Line
	3150 3250 3150 3400
$Comp
L power:GND #PWR0150
U 1 1 60FE0C8C
P 3150 4400
F 0 "#PWR0150" H 3150 4150 50  0001 C CNN
F 1 "GND" H 3155 4227 50  0000 C CNN
F 2 "" H 3150 4400 50  0001 C CNN
F 3 "" H 3150 4400 50  0001 C CNN
	1    3150 4400
	1    0    0    -1  
$EndComp
Wire Wire Line
	3150 4400 3150 4250
$Comp
L Device:C C32
U 1 1 60FE0C93
P 4550 4500
F 0 "C32" H 4436 4454 50  0000 R CNN
F 1 "10nF" H 4436 4545 50  0000 R CNN
F 2 "Capacitor_SMD:C_0402_1005Metric" H 4588 4350 50  0001 C CNN
F 3 "~" H 4550 4500 50  0001 C CNN
F 4 "3013347" H 4550 4500 50  0001 C CNN "ordercode"
F 5 "farnell" H 4550 4500 50  0001 C CNN "supplier"
	1    4550 4500
	1    0    0    1   
$EndComp
$Comp
L Device:C C33
U 1 1 60FE0C99
P 4900 4500
F 0 "C33" H 5015 4546 50  0000 L CNN
F 1 "100nF" H 5015 4455 50  0000 L CNN
F 2 "Capacitor_SMD:C_0402_1005Metric" H 4938 4350 50  0001 C CNN
F 3 "~" H 4900 4500 50  0001 C CNN
F 4 "2524678" H 4900 4500 50  0001 C CNN "ordercode"
F 5 "farnell" H 4900 4500 50  0001 C CNN "supplier"
	1    4900 4500
	1    0    0    -1  
$EndComp
Wire Wire Line
	4550 4150 4900 4150
Wire Wire Line
	4900 4350 4900 4150
Wire Wire Line
	4550 4350 4550 4150
Connection ~ 4550 4150
$Comp
L power:GND #PWR0151
U 1 1 60FE0CA3
P 4550 4750
F 0 "#PWR0151" H 4550 4500 50  0001 C CNN
F 1 "GND" H 4555 4577 50  0000 C CNN
F 2 "" H 4550 4750 50  0001 C CNN
F 3 "" H 4550 4750 50  0001 C CNN
	1    4550 4750
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR0152
U 1 1 60FE0CA9
P 4900 4750
F 0 "#PWR0152" H 4900 4500 50  0001 C CNN
F 1 "GND" H 4905 4577 50  0000 C CNN
F 2 "" H 4900 4750 50  0001 C CNN
F 3 "" H 4900 4750 50  0001 C CNN
	1    4900 4750
	1    0    0    -1  
$EndComp
Wire Wire Line
	4900 4750 4900 4650
Wire Wire Line
	4550 4750 4550 4650
$Comp
L power:GND #PWR0153
U 1 1 60FE0CB1
P 5250 4750
F 0 "#PWR0153" H 5250 4500 50  0001 C CNN
F 1 "GND" H 5255 4577 50  0000 C CNN
F 2 "" H 5250 4750 50  0001 C CNN
F 3 "" H 5250 4750 50  0001 C CNN
	1    5250 4750
	1    0    0    -1  
$EndComp
Wire Wire Line
	5250 4250 5250 4350
Connection ~ 4900 4150
Wire Wire Line
	4900 4150 5350 4150
$Comp
L power:+3V3 #PWR0154
U 1 1 60FE0CBA
P 4550 4050
F 0 "#PWR0154" H 4550 3900 50  0001 C CNN
F 1 "+3V3" H 4565 4223 50  0000 C CNN
F 2 "" H 4550 4050 50  0001 C CNN
F 3 "" H 4550 4050 50  0001 C CNN
	1    4550 4050
	1    0    0    -1  
$EndComp
Text HLabel 5150 3650 0    50   Input ~ 0
I2S_SD_MODE
Text HLabel 5150 3750 0    50   Input ~ 0
I2S_BCLK
Text HLabel 5150 3850 0    50   Input ~ 0
I2S_LRCLK
Text HLabel 5150 3950 0    50   Input ~ 0
I2S_DIN
Wire Wire Line
	5150 3950 5350 3950
Wire Wire Line
	5350 3850 5150 3850
Wire Wire Line
	5150 3750 5350 3750
$Comp
L Device:C C34
U 1 1 60FE0CD7
P 7250 4300
F 0 "C34" H 7050 4300 50  0000 L CNN
F 1 "220pF" H 6950 4200 50  0000 L CNN
F 2 "Capacitor_SMD:C_0402_1005Metric" H 7288 4150 50  0001 C CNN
F 3 "~" H 7250 4300 50  0001 C CNN
F 4 "2812289" H 7250 4300 50  0001 C CNN "ordercode"
F 5 "farnell" H 7250 4300 50  0001 C CNN "supplier"
	1    7250 4300
	1    0    0    -1  
$EndComp
$Comp
L Device:C C35
U 1 1 60FE0CDD
P 7550 4300
F 0 "C35" H 7665 4346 50  0000 L CNN
F 1 "220pF" H 7665 4255 50  0000 L CNN
F 2 "Capacitor_SMD:C_0402_1005Metric" H 7588 4150 50  0001 C CNN
F 3 "~" H 7550 4300 50  0001 C CNN
F 4 "2812289" H 7550 4300 50  0001 C CNN "ordercode"
F 5 "farnell" H 7550 4300 50  0001 C CNN "supplier"
	1    7550 4300
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR0156
U 1 1 60FE0CE3
P 7250 4750
F 0 "#PWR0156" H 7250 4500 50  0001 C CNN
F 1 "GND" H 7255 4577 50  0000 C CNN
F 2 "" H 7250 4750 50  0001 C CNN
F 3 "" H 7250 4750 50  0001 C CNN
	1    7250 4750
	1    0    0    -1  
$EndComp
$Comp
L power:GND #PWR0157
U 1 1 60FE0CE9
P 7550 4750
F 0 "#PWR0157" H 7550 4500 50  0001 C CNN
F 1 "GND" H 7555 4577 50  0000 C CNN
F 2 "" H 7550 4750 50  0001 C CNN
F 3 "" H 7550 4750 50  0001 C CNN
	1    7550 4750
	1    0    0    -1  
$EndComp
Wire Wire Line
	7550 4750 7550 4450
Wire Wire Line
	7250 4750 7250 4450
Connection ~ 7550 3650
Connection ~ 7250 3950
Text Label 7650 3650 0    70   ~ 0
VO+
Text Label 7650 3950 0    70   ~ 0
VO-
Wire Wire Line
	7900 3650 7900 3750
Wire Wire Line
	7900 3750 7950 3750
Wire Wire Line
	7550 3650 7900 3650
Wire Wire Line
	7950 3850 7900 3850
Wire Wire Line
	7900 3850 7900 3950
Wire Wire Line
	7250 3950 7900 3950
Text HLabel 7950 3750 2    50   Output ~ 0
SPKOUT+
Text HLabel 7950 3850 2    50   Output ~ 0
SPK_OUT-
Wire Wire Line
	5150 3650 5350 3650
Wire Wire Line
	5350 4350 5250 4350
Connection ~ 5250 4350
Wire Wire Line
	5250 4350 5250 4750
Wire Wire Line
	6550 3950 7250 3950
Wire Wire Line
	6550 3650 7550 3650
$EndSCHEMATC