HIGH-PRECISION VOLTAGE DETECTOR
S-807 Series
5. Oscillation
In applications where a resistor is connected to the voltage detector input (Figure 11 and 12), the through-type current
generated when the output goes from low to high (release) causes a voltage drop equal to [through-type current]×[input
resistance] across the resistor. When the input voltage resultantly drops below the detection voltage -V
DET
, the output
voltage returns to its low level. In this state, the through-type current -- and its resultant voltage drop -- have disappeared,
and the output goes back from low to high. Again, a through-type current is generated, a voltage drop appears, and the
process repeats. Oscillation refers to this unstable condition
.
•
Power reset mis-implementation
•
Mis-implementation with input voltage
divider
V
DD
R
V
IN
Di
(CMOS output)
S-
807XXAL
OUT
/SL
V
DD
RA
V
IN
(CMOS output)
S-
807XXAL
OUT
/SL
C
V
SS
Figure 11
V
SS
RB
Figure 12
Seiko Instruments Inc.
25
SII [ SEIKO INSTRUMENTS INC ]
