S-807 Datasheet, PDF (41/42 Pages) Seiko Instruments Inc – HIGH-PRECISION VOLTAGE DETECTOR

Collection of Product FAQs
Author: Hamaguchi Masanao
Date: 98/11/12 (Thursday) 10:17 (Modified: 98/12/14 (Monday) 16:42)
<Information level>
A:
Public (Printing O.K.)
Index:
B: Technical
<Product>
Division name: 01 IC
Category 1: 11 Power Supply
Category 2:
Cal No.:
1. Voltage Detectors
S-807
Related Documents:
Question:
What is the method for calculating delay-time of the power-on clear circuit?
Answer:
The delay time (power-on clear time) produced in a power-on clear circuit using the S-807xxAN can be
found by substituting constants in the following formula:
Tdelay =
1× C × R × Ln (1
-
Vdet +
Vdd
)
Tdelay: Delay time [sec]
C: External capacitance value [F]
R: Resistance value [Ω]
V det+: S-807xxAN Series release voltage [V]
Vdd: Supply voltage [V]
Vdd
V
Supply voltage (Vdd)
R
S-807xxAN
Pull-up resistor
C
Delay time
Note: Set R to less than 7.5 kΩ to prevent oscillation.
S-807xxAN release voltage (Vdet+)
S-807 input voltage
40