BUILT-IN DELAY CIRCUIT (EXTERNAL DELAY TIME SETTING) VOLTAGE DETECTOR WITH SENSE PIN
Rev.2.1_01
S-1004 Series
3. Delay circuit
The delay circuit has the function that adjusts the release delay time (tRESET) from when the SENSE pin voltage
(VSENSE) reaches release voltage (+VDET) to when the output from OUT pin inverts.
tRESET is determined by the delay coefficient, the delay capacitor (CD), and the release delay time when the CD pin
is open (tRESET0), and calculated by the equation below.
tRESET [ms] = Delay coefficient × CD [nF] + tRESET0 [ms]
Table 13
Delay Coefficient
Operation
Temperature
Min.
1.78
2.30
2.68
Typ.
2.29
2.66
3.09
Max.
3.13
3.07
3.57
Ta = +85°C
Ta = +25°C
Ta = −40°C
Table 14
Release Delay Time when CD Pin is Open (tRESET0
)
Operation
Temperature
Min.
Typ.
Max.
Ta = +85°C
Ta = +25°C
Ta = −40°C
0.020 ms
0.021 ms
0.024 ms
0.049 ms
0.059 ms
0.074 ms
0.130 ms
0.164 ms
0.202 ms
Caution 1. Mounted board layout should be made in such a way that no current flows into or flows from
the CD pin since the impedance of the CD pin is high, otherwise correct delay time cannot be
provided.
2. There is no limit for the capacitance of CD as long as the leakage current of the capacitor can
be ignored against the built-in constant current value (30 nA to 200 nA).
3. The detection delay time (tDET) cannot be adjusted by CD.
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