12/20
XC6118 Series
④ When the sense pin voltage continues to increase up to the release voltage level (VDF+VHYS), the N-ch transistor (M1) for
the delay capacitance (Cd) discharge will be turned OFF, and the delay capacitance (Cd) will start discharging via a delay
resistor (R
DELAY
). The inverter (Inv
.
1) will operate as a comparator (Rise Logic Threshold: VTLH=VTCD, Fall Logic
Threshold: V
THL=VSS) while the sense pin voltage keeps higher than the detect voltage (VSEN > VDF).
⑤ While the delay capacitance pin voltage (VCD) rises to reach the delay capacitance pin threshold voltage (VTCD) with the
sense pin voltage equal to the release voltage or higher, the sense pin will be charged by the time constant of the RC series
circuit. Assuming the time to the release delay time (t
DR
), it can be given by the formula (1).
t
DR
=-R
DELAY
×
Cd
×
ln(1-V
TCD
/V
IN
)
…
(1)
The release delay time can also be briefly calculated with the formula (2) because the delay resistance is 2.0MΩ(TYP.) and
the delay capacitance pin threshold voltage is V
IN /2 (TYP.)
t
DR
=R
DELAY
×
Cd
×
0.69
…
(2)
*
：
R
DELAY
is 2.0M
Ω（
TYP.
）
As an example, presuming that the delay capacitance is 0.68μF, t
DR
is :
2.0
×
10
6
×
0.68
×
10
-6
×
0.69=938(ms)
* Note that the release delay time may remarkably be short when the delay capacitance (Cd) is not discharged to the ground
(=V
SS) level because time described in ③ is short.
⑥ When the delay capacitance pin voltage reaches to the delay capacitance pin threshold voltage (VCD=VTCD), the inverter
(Inv.1) will be inverted. As a result, the output voltage changes into the “High” (=V
IN) level. t
DR0
is defined as time which
ranges from V
SEN=VDF+VHYS to the VOUT of “High” level without connecting to the Cd.
⑦ While the sense voltage is higher than the detect voltage (VSEN > VDF), the delay capacitance pin is charged until the delay
capacitance pin voltage becomes the input voltage level. Therefore, the output voltage maintains the “High”(=V
IN) level.
●Function Chart
TRANSITION OF V
OUT
CONDITION *1
V
SEN
Cd
①
②
L
H
L
L
L
H
H
⇒
L
L
⇒
L
H
L
⇒
L
H
H
H
⇒
H
●Release Delay Time Chart
DELAY
CAPACITANCE [Cd]
(μF)
RELEASE DELAY TIME [tDR]
(TYP.)
(ms)
RELEASE DELAY TIME [tDR] *2
(MIN. ~ MAX.)
(ms)
0.010 13.8 11.0 ~ 16.6
0.022 30.4 24.3 ~ 36.4
0.047 64.9 51.9 ~ 77.8
0.100 138 110 ~ 166
0.220 304 243 ~ 364
0.470 649 519 ~ 778
1.000 1380 1100 ~ 1660
●Example
ex. 1) V
OUT
ranges from ‘L’ to ‘H’ in case of VSEN = ‘H’ (VDR≧VSEN), Cd=’H’ (VTCD≧Cd) while VOUT is ‘L’.
ex. 2) V
OUT
maintains ‘H’ when Cd ranges from ‘H’ to ‘L’, VSEN=’H’ and Cd=’L’ when V
OUT
becomes ‘H’ in ex.1.
■OPERATIONAL EXPLANATION (Continued)
* The release delay time values above are calculated by using the formula (2).
*2: The release delay time (t
DR
) is influenced by the delay capacitance Cd.
*1: V
OUT
transits from condition ① to ② because of the combination of V
SEN
and V
CD
,V
IN
.
V
IN
should be more than the lowest operation voltage.
