6. FUNCTIONAL DESCRIPTION
26
EPSON
S1D15722D01B000 Technical Manual (Rev.1.1)
If there is a resistance component R between the system ground and IC’s V
SS
pin, the IC’s board potential
V
SS
viewed from the system ground experiences fall of potential of
∑
×
=
∆
R
I
V
(where
∑
I
: IC is the total amount of the current consumed by IC)
Therefore, the temperature sensor output (Fig.6.22: SVD20) viewed from the system ground is also
influenced similarly. That is,
∆
V has an impact on the temperature sensor output (Fig.6.22: SVD21) viewed
from the IC’s V
DD
defined in the specifications.
To eliminate the impact of
∆
V as much as possible, adopt the design and usage with consideration given to
three points below:
•
Decrease the resistance value between the system ground and IC’s V
SS
pin as low as possible, including ITO
resistance when mounting COG.
•
Measure the temperature sensor output voltage with the current consumed by IC reduced as much as possible
by placing the IC in the power-saving mode.
•
Minimize the impact caused by the IC’s external circuits by leaving the system to be used under certain
temperature and allowing the system to store the SVD2 voltage measured while operating the system as the
reference voltage.
Содержание S1D15722 Series
Страница 1: ...Rev 1 1 S1D15722D01B000 Technical Manual ...