WT8072
PIR CONTROLLER
GENERAL DESCRIPTION
WT 8072 is a PIR (passive infra-red) controller, using analog mixing digital design technique and
manufactures by CMOS process which can either drive TRIAC or RELAY depending on users' choice.
With special noise immunity technique, WT8072 is the most stable PIR controller you can find on the
market. More than this, there are few components needed in its application circuit which can reduce
material cost and increase competitive.
FEATURES
*HIGH NOISE IMMUNITY.
*DRIVE EITHER RELAY OR TRIAC.
*ADJUSTABLE LIGHT ON DURATION.
*TRIAC CAN BE EITHER SHUNT OR SERIAL CONNECTED.
*PIR INPUT.
*CDS INPUT.
PIN CONFIGURATION
∙
PIN DESCRIPTION
Pin No.
1
2
3
4
5
6
Pin Name I/O
Description
UOU1
First stage OP amp output
NII 1
First stage OP amp positive input
II 1
First stage OP amp negative input
VREF
Stable reference voltage
GND
System ground
TB
Time base for 1. The delay time of receiving PIR singnal to sent a puls to
trigger TRIAC or a high signal to trigger relay.
The delay time = R x C x 32.
The PIR signal patented and accepted only if the signal cycle greater than R
x C x 768 .When state of relay or TRIAC is changing form active into
inactive mode. It takes more than R x C x 4069, then system is able to
receive PIR signal again.
2.The flash cycle show the beginning of auto mode.
Note: Width of TRIAC pulse = R x C x 2.
Flash cycle: R x C x 32768
10 K < R < 1M Ohm
100pF < C < 0.1 Uf (Reference Diagram 1)
QTEST
For testing only
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Weltrend Semiconductor, Inc.
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WT8072
PIR CONTROLLER
8
TCI
To set up the timing of how long Triac or relay is active.
During the period, if the system receives the PIR signal, then it restarts
counting the timing again.
The range for R: 10K < R < 1M Ohm
C: 100uF< C < 0.1 uF
(Reference Diagram 2)
Connected to a CDS for inhibiting relay or TRIAC being triggered.
If TRIAC or relay has already being triggered by PIR signal and turned into
active mode, then CDS can not inhibit PIR again.
To trigger TRIAC, active low
Sink current: 15 mA max.
To drive relay, active high
Sink current: 10 mA max.
Source current: 10 mA max.
Detect zero cross of AC line under remote mode function.
Operation voltage: 5V, stand by current: 1mA
nd
2 stage OP amp negative input
nd
2 stage OP amp positive input
nd
2 stage OP amp output
9
10
11
12
13
14
15
16
CDS
TRIAC
RELAY
ZCD
VDD
II2
NII2
UOU2
DIAGRAM 1, 2
Weltrend Semiconductor, Inc.
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WT8072
PIR CONTROLLER
Absolute Maximum Ratings
Parameter
POWER SUPPLY Vdd WITH REPECT TO Vss
VOLTAGE ON ANY PIN
OPERATING TEMPERATURE
STORAGE TEMPERATURE
SYMBOL
Vdd-Vss
Top
VALUE
5.6
-0.3-5.6
0-70
-65-150
Units
V
V
C
C
ELECTRICAL CHARACTERISTICS
Symbol
Parameter
Vdd
SUPPLY VOLTAGE
Ist
STANDY CURRENT
Idd
OPERATING CURRENT
Vref
Iref
STABLE VOLTAGE
SOURCE CURRENT OF Vref
RIPPLE OF Vref
INPUT
AND
OUTPUT
REGULATION OF Vref
TIME
BASE
OPERATING
FREQUENCY
CDS OPERATING TRIGGER
Condition
Min.
4.2
0.9
1.8
3.0
200
Typ.
5
1.0
3.2
Max.
5.5
1.2
2.5
3.4
0.5
0.3%
15
1.3
0.6
2.6
9
11.6
0.03
4.6
0.08
37.8
16
1.7
0.9
3.5
10.4
13
17
2.1
1.1
4.4
17.4
21
9.3
1290
14.9
11170
5
5
18.8
15
50
mA
mA
V
mA
uA
Unit
V
mA
mA
V
uA
mV
KHZ
V
V
uA
mA
mA
Sec.
1.8mA, TRIAC
2.5mA, RELAY
Vdd>4.2V
Ftb
Vt+
Vt-
CDS OPREATING TRIGGER
Icds
CDS SOURCE CURRENT
Isource CDS
OUTPUT
SOURCE
CURRENT
Isink
CDS OUTPUT SINK CURRENT
Tout1
TIMER DURATION OF OUT 1
C=0.001uF
R=4.7K-1M
C=0.01uF
R=4.7K-1M
C=100uF
R=4.7K-1M
C=0.1uF
R=4.7K-1M
Irs
RELAY SOURCE CURRENT
Irsink
RELAY SINK CURRENT
Vro
RELAY OPERATING VOLTAGE
18.8V: RELAY ON
13.1V: RELAY OFF
Itsink
TRIAC SINK CURRENT
Itsource TRIAC SOURCE CURRENT
13.1
Weltrend Semiconductor, Inc.
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WT8072
PIR CONTROLLER
TYPICAL APPLICATION
HOME SECURITY SYSTEM.
AUTO LIGHT SYSTEM FOR GARDEN, GARAGE, HALLWAY, STAIRCASE, PORCH, BATHROM, AND
ETC.
AUTO SWITCH FOR VENTILATION FAN.
AUTO NOTICE SYSTEM FOR OFFICE, STORAGE, AND ETC.
ORDERING INFORMATION
Ordering Number
WT8072
WT8072H
Package Type
P-DIP 16L
CHIP FORM
Weltrend Semiconductor, Inc.
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WT8072
PIR CONTROLLER
Weltrend Semiconductor, Inc.
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