PT8A2641 Datasheet, PDF (8/13 Pages) Pericom Semiconductor Corporation – PIR Sensor Light Switch

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Figure 7 ZC override timing
Operating
Mode
AUTO
flash
ON
ZC
PT8A2641-2642/2645-2648
PIR Sensor Light Switch
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flash
AUTO
flash
ON
5 hours
flash
AUTO
Any operations during flash period are inactive, the flash period is about 3s from AUTO to ON, 3s from ON to AUTO.
COMPO: COMPO is output from comparator, it can be output at pin 10 if needed. Signal from two-stage opamp outputs to a
window comparator as pre-operation, COMPO outputs active positive pulses with various width once signal beyond window
level. Whether an active PIR signal is detected, see trigger timming diagram below for detail.
Trigger timing
Figure 8 Trigger timing
RSTB
CDS
CDSO
OP2O
COMPO
Detect
Enable
Test
Enable
RELAY
TRIAC
+trigger
level
-trigger
level
Warm up 40s
10s
5s
>T mt
< Tmt
(Note1)
(Note2)
pulse out
ON
ON _(Note3)
Note: 1. One measurable trigger width (Tmt) from comparator output is 24ms~ 32ms which varies with frequency of system
oscillator (typical system frequency=16KHz ).
2. The output is activated if the trigger signal conforms to the following criteria:
 A trigger signal sustain duration:0.34 seconds.
 2 trigger signals within 2 seconds with one of the trigger signal sustain:0.16 seconds.
 More than 3 measurable triggers within 2 seconds.
3. The output duration is set by an external RC that is connected to the OSCD pin.
Retrigger
If another signal is attained in trigger hold time, the circuit will be retriggered, and the trigger hold time will be started from
this time.
12-07-0006
PT0192-3 07/06/12
8