HIGH-PRECISION VOLTAGE DETECTOR

S-807 Series

Seiko Instruments Inc.

39

3. Change of detection voltage

In Nch open-drain output products of the S-807 Series, detection voltage can be changed with resistance dividers or diodes

as shown in Figures 29 and 30. In Figure 29, hysteresis width is also changed.

Notes

• In CMOS output products of S-807 Series, high through current flows when detecting or releasing. If a high impedance is

connected to the input, oscillation may be caused by the through current when lowering the voltage during releasing.

• In TO-92 products, since there are projections and resin burrs on the roots of the lead terminals formed at the Tiebar-cut, do

not solder to them.

• When designing for mass production using an application circuit described here, take into account the deviation of

components and temperature characteristics.

• Seiko Instruments Inc. cannot take any responsibility for the patents on the circuits described here.

Figure 30

Figure 29

RB

RA

OUT

S-

807XX

AN/SN

+

-

(Nch open-drain

products)

(RA

≤7.5kΩ)

OUT

S-

807XX

AN/SN

(Nch open-drain

products)

Figure 29

Detection voltage=

Hysteresis width=

•-V

DET

RA+RB

RB

•-V

HYS

RA+RB

RB

Note 1: The hysteresis width will be a little

wider than the value of the formula

above, because of the through current,

if RA and RB are larger.

Note 2: RA should be 7.5k

Ω or less for

purpose of protection against

oscillation.