The HT7612B is a CMOS LSI chip designed for use in automatic PIR lamp control. It can operate with a 2-wire configuration for triac applications or with a 3-wire configuration for relay applications. The chip is equipped with operational amplifiers, a comparator, timer, a zero crossing detector, control circuit, a voltage regulator, a system oscillator, and an output timing oscillator. Its PIR sensor detects infrared power variations induced by the motion of a human body and transforms it to a voltage variation. If the PIR output voltage variation conforms to the criteria (refer to the functional description), the lamp is turned on with an adjustable duration.
The HT7612B offers three operating modes (ON, AUTO, OFF) which can be set through the MODE pin. While the chip is working in the AUTO mode the user can override it and switch to the TEST mode, or manual ON mode, or return to the AUTO mode by switching the power switch. The chip is enclosed in a 16 pin DIP/SOP.
Operating voltage: 2.7V ~ 5.5V
Standby current typical:
CDS debounce time:
HT7612: 15~20 seconds
HT7612B: < 3 seconds
High noise immunity
40 second power-on delay
10 second high speed warm-up for test mode
1~3783 second adjustable PIR turn on time
Output drive for Relay, TRIAC and LED
Output drive buzzer alarm
Low voltage detector
16-pin DIP/NSOP package