HT7610A/HT7610B/HT7611A/HT7611B

Rev. 1.60

5

March 21, 2013

ZC

ZC is a CMOS input structure. It receives AC line fre-

quency and generates zero crossing pulses to synchro-

nize the triac driver. By effective ZC signal switching

(switch OFF/ON 1 or 2 times within 3 seconds by mask

option), the chip provides the following additional func-

tions:

Within 10 seconds after power-on, effective ZC

switching will force the chip to enter the test mode.

During the test mode, the outputs will be active for a

duration of 2 seconds each time a valid PIR trigger

signal is received. If a time interval exceeds 32 sec-

onds without a valid trigger input, the chip will auto-

matically enter the AUTO mode.

When the chip is working in an AUTO mode

(MODE=open), the output is activated by a valid PIR

trigger signal and the output active duration is con-

trolled by an OSCD oscillating period. The lamp can

be switched always to

²ON² from the AUTO mode by

either switching the MODE pin to VDD or switching

the ZC signal by an OFF/ON operation of the power

switch (OFF/ON once or twice within 3 seconds by

mask option). The term

²override² refers to the

change of operating mode by switching the power

switch. The chip can be toggled from ON to AUTO by

an override operation. If the chip is overridden to ON

and there is no further override operation, it will auto-

matically return to AUTO after an internal preset ON

time duration has elapsed. This override ON time du-

ration is 8 hours.

The chip provides a mask option to determine the out-

put flash times (3 times) when changing the operating

mode. It will flash 3 times at a 1Hz rate each time the

chip changes from an AUTO mode to another mode or

flash 3 times at a 2Hz rate when returning to the

AUTO mode. But if the AUTO mode is changed by

switching the MODE switch it will not flash.

RST

RST is used to reset the chip. It is internal pull-high and

active low.

time is the default (40 secs).

Power-on Initial

The PIR signal amplifier requires a warm up period after

power-on. The input should be disabled during this period.

In the AUTO mode within the first 10 seconds of

power-on initialization, the chip allows override control

to enter the test mode. After 40 seconds of the initial

time the chip allows override control between ON and

AUTO. It will remain in the warm up period if the total ini-

tial time has not elapsed after returning to AUTO.

In case that the ZC signal disappears for more than 3

seconds, the chip will restart the initialization operation.

However, the restart initial time is always 40 seconds

as shown in the Fig.1.

Mask Options

The HT761x offers mask options to select the output

flash (3 times) when changing the operating mode. The

chip will flash 3 times at a 1Hz rate each time it changes

from AUTO to another mode and flash 3 times at a 2Hz

rate when it returns to the AUTO mode. However the

chip will not flash if the mode is changed by switching

the MODE switch.

eration of power switch within 3 seconds. Once for

HT7611A/HT7611B and twice for HT7610A/HT7610B.

operation. Flash for HT7610A/HT7610B and no flash

for HT7611A/HT7611B.

Z C

A U T O

O N

A U T O

A U T O

O p e r a t i n g

M o d e

8 h o u r s

O N

f l a s h

f l a s h

f l a s h

f l a s h

ZC Override Timing

R E S T

R S T

1 0 0 m F

V C C

V E E

Fig.1 RST Application Example