S-809XXC Datasheet, PDF (17/36 Pages) Seiko Instruments Inc – ULTRA-SMALL PACKAGE HIGH-PRECISION VOLTAGE DETECTOR WITH DELAY CIRCUIT (EXTERNAL DELAY TIME SETTING)

ULTRA-SMALL PACKAGE HIGH-PRECISION VOLTAGE DETECTOR WITH DELAY CIRCUIT (EXTERNAL DELAY TIME SETTING)
Rev.3.3_00
S-809xxC Series
5. Oscillation
In applications where a resistor is connected to the voltage detector input (Figure 22), taking a CMOS
active low product for example, the through-type current, which is 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 drops below the detection voltage (−V_DET) as a result, the output voltage
goes to low level. In this state, the through-type current stops and its resultant voltage drop disappears,
and the output goes from low to high. The through-type current again generated, a voltage drop appears,
and repeatiing the process finally induces oscillation.
VDD
R_A
V_IN
S-809xxCL
OUT
R_B
VSS
Figure 22 Example for Bad Implementation of Input Voltage Divider (CMOS Output Products)
„ Precautions
• Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in
electrostatic protection circuit.
• In CMOS output products of the S-809xxC series, the through-type current flows at the detection and the
release. If the input impedance is high, oscillation may occur due to the voltage drop by the through-type
current during releasing.
• When designing for mass production using an application circuit described herein, the product deviation
and temperature characteristics should be taken into consideration. SII shall not bear any responsibility
for the patents on the circuits described herein.
• SII claims no responsibility for any and all disputes arising out of or in connection with any infringement of
the products including this IC upon patents owned by a third party.
Seiko Instruments Inc.
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