ULTRA-SMALL PACKAGE HIGH-PRECISION VOLTAGE DETECTOR
S-808xxC Series
Rev.3.2_00
2. Power-on Reset Circuit
A power-on reset circuit can be constructed using Nch open-drain output product of S-808××C Series.
VDD
Di*2
VIN
R*1
S-
(R≤75 kΩ)
808xxCN
OUT
Nch open-drain products)
(
C
VSS
*1. Resistor R should be 75 kΩ or less to prevent oscillation.
*2. Diode Di instantaneously discharges the charge stored in the capacitor (C) at the power falling,Di can be
removed when the delay of the falling time is not important.
Figure 27
VDD
(V)
OUT
(V)
t (s)
t (s)
Figure 28
Remark When the power rises sharply as shown in the Figure 29 left, the output may goes to the high level
for an instant in the undefined region where the output voltage is undefined since the power
voltage is less than the minimum operation voltage.
VDD
(V)
OUT
(V)
t (s)
t (s)
Figure 29
Seiko Instruments Inc.
33
SII [ SEIKO INSTRUMENTS INC ]
