ULTRA-SMALL PACKAGE HIGH-PRECISION VOLTAGE DETECTOR
S-1000 Series
Rev.2.3_00
3. Change of detection voltage
In Nch open-drain output products of the S-1000 series, detection voltage can be changed using resistance dividers or
diodes as shown in Figures 29 to 30. In Figure 29, hysteresis width also changes.
VDD
VDD
Vf1
Vf2
*1
RA
VIN
VIN
C*1
S-1000N
OUT
S-1000N
OUT
+
−
(Nch open-drain
output product)
RB
(Nch open-drain
output products)
VSS
Detection voltage = Vf1+Vf2+(−VDET
Figure 30
VSS
Detection voltagae = RA + RB • −VDET
)
RB
RA + RB
Hysterisis width =
• VHYS
RB
*1. RA should be 75 kΩ or less, and C should be 0.01 µF
or more to prevent oscillation.
If C is not connected, RA should be 800 Ω or less.
Caution If RA and RB are large, the hysteresis width
may also be larger than the value given by
the above equation due to the through-type
current (which flows slightly in an Nch
open-drain product).
Figure 29
Caution The above connection diagram and constants do not guarantee correct operation. Perform sufficient
evaluation using the actual application to set the constants.
Seiko Instruments Inc.
23
SII [ SEIKO INSTRUMENTS INC ]
