APPENDIX
Appendix 7. Countermeasure against noise
(2) Processing for analog power source pins, etc.
ꢀ Use independent power sources for the Vcc, AVcc and VREF pins.
ꢀ Insert capacitors between the AVcc and AVss pins, and between the VREF and AVss pins.
Reasons: Prevents the A-D converter and D-A converter from noise on the Vcc line.
M37906
Reference values
AVcc
C1 ≥ 0.47 µF
C2 ≥ 0.47 µF
V
REF
C1
C2
Note : Connect capacitors using the
AVss
AN
thickest, shortest wiring possible.
i
(sensor, etc.)
Fig. 7 Processing for analog power source pins, etc.
7906 Group User’s Manual Rev.2.0
20-99
RENESAS [ RENESAS TECHNOLOGY CORP ]
