Schematics

OX(NO2):
R3resistortargetcurrent:26mA
R3resistorselection:(3.3V-1.7V)/.026A=61.5ohm
R3resistorpower=.026A*.026A*61.5ohm=41mW
RED(CO):
R8resistortargetcurrent:32mA
R8resistorselection:(3.3V-2.4V)/.032A=28.1ohm
R8resistorpower=.032A*.032A*28.1ohm=29mW
NH3:
R15resistortargetcurrent:30mA
R15resistorselection:(3.3V-2.2V)/.03A=36.7ohm
R15resistorpower=.03A*.03A*36.7ohm=33mW
GND
GND
GND
GND
1uF1uF
GND
SSM3K56MFV,L3F
62R0805RMCF0805FT62R0
28R0805RMCF0805FT28R0
56k
56k
1uF
GND
SSM3J56MFV,L3F
36R50805RMCF0805FT36R5
GND
56k
3V3AP7333-33SRG
GND
J2
1
2
3
4
5
13_P0.7/AIN2/RXD
1
14_P1.7/INT1/AIN0
2
GND
3*2
SDA_P1.6/[SDA]/TXD_1/ICPDA
4
VDD
5
1_P1.5/PWM5/IC7/SS
6
2_P1.0/PWM2/IC2/SPCLK
7
7_P1.1/PWM1/IC1/AIN7/CLO
8
3_P1.2/PWM0/IC0
9
4_P1.4/SDA/FB/[PWM1]
10
INT_P1.3/SCL/[STADC]
11
5_P0.0/PWM3/IC3/MOSI/T1
12
6_P0.1/PWM4/IC4/MISO
13
SCL_P0.2/ICPCK/RXD_1/[SCL]
14
8_P0.3/[PWM5]/IC5/AIN6
15
9_P0.4/AIN5/STADC/[PWM3]/IC3
16
10_P3.0/INT0/OSCIN/AIN1
17
P2.0_INPUT/RST
18
11_P0.6/TXD/AIN3
19
12_P0.5/[PWM2]/IC6/T0/AIN4
20
MCU1
Vin:2.4V-5.5V,(ADC2.7-5.5V)MS51XB9AE
PROG_RST
4
2
1
3
C2C3
Q1
1 8
RN1-1
330R
2 7
RN1-2
330R
3 6
RN1-3
330R
4 5
RN1-4
330R
R2
R8
R9
R10
C16
GND_OX
J
GND_RED
B
RH_RED
G
RS_RED
H
RH_OX
K
RS_OX
A
RS1_NH3
D
RS2_NH3
F
RH1_NH3
C
RH2_NH3
E
Q5
R14
R15
IN
OUT
GND
U1
SDA_5V_PROG_DATA
SDA_5V_PROG_DATA
5V
5V
5V
5V
5V
INT_5V
INT_5V
SCL_5V_PROG_CLK
SCL_5V_PROG_CLK
PROG_RST
LED_RED
LED_RED
LED_BLUE
LED_BLUE
LED_GREEN
LED_GREEN
SENSOR_3V3
SENSOR_3V3
SENSOR_3V3
SENSOR_3V3
OX_SENSE
OX_SENSE
RED_SENSE
RED_SENSE
HEATERS
HEATERS
HEATERS
HEATERS
NH3_SENSE
NH3_SENSE
HEATERS_EN
HEATERS_EN
R
G
B
G
S
D
300mALowDropoutRegulator
CapShared
withLDO
MICS-6814AnalogNO2&CO&NH3Sensor
Breakoutconnectorandreverseprotection
LDOforheaterandsensorpower
RGBLED
MCU