SN8P2740 Series
ADC, OP-amp, Comparator 8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 115
Version 2.0
13.6 ADC APPLICATION CIRCUIT
VCC
GND
0.1uF
Analog Signal Input
47uF
0.1uF
External High
Reference Voltage
Main Power Trunk
AINn/P4.n
VSS
AVREFH
MCU
A
B
C
The analog signal is inputted to ADC input pin
“AINn/P4.n”. The ADC input signal must be through a 0.1uF capacitor
“A”. The 0.1uF capacitor is set between ADC input pin and VSS pin, and must be on the side of the ADC input pin as
possible. Don
‟t connect the capacitor‟s ground pin to ground plain directly, and must be through VSS pin. The capacitor
can reduce the power noise effective coupled with the analog signal.
If the ADC high reference voltage is from external voltage source, the external high reference is connected to AVREFH
pin (P4.0). The external high reference source must be through a 47uF
”C” capacitor first, and then 0.1uF capacitor “B”.
These capacitors are set between AVREFH pin and VSS pin, and must be on the side of the AVREFH pin as possible.
Don
‟t connect the capacitor‟s ground pin to ground plain directly, and must be through VSS pin.