long range reset ic which can send reset signal at every 6 h

long range reset ic

Please share some ideas regarding long range reset ic.

I am forced to design a reset circuit which will automatically reset the hardware circuit at every 6 hours.

Condition's are given as follows.

A. Ic should be non-programable.

B. Relay should not be used in the circuit.

My question is

Please suggest me the ic which can send reset signal at every 6 hours once and how can i interface that reset circuit without using relay.

Re: long range reset ic

interfacing can b done without relay,there are so many transisitor,ic available,u can choose one, once ur reset circuit completed.

is it a single pulse, after 6 hours? let me know. i mean u wanna make circuit which give a pulse after 6 hours automatically?thn whr interfacing needed?

Re: long range reset ic

use ewb to open this file

Re: long range reset ic

I attached the block diagram in pdf format. please find it.

Actually the power supply is directly given to the instrument, the problem is that unit get's hanged due to some reason's that's why the reset circuit is introduced in between powersupply and the instrument.

The reset circuit will give reset signal at every 6 hour's automatically (the ic used should be non-programable ic)

in that block diagram the block"suggest me please" relay should not be used, Please suggest me other components.

Re: long range reset ic

Hi,
In such applications normal practice is to use a watchdog timer to reset the internal logic instead of disconnecting the supply. A watchdog timer can be made using a retriggerable monoshot followed by a standard monoshot which will be triggered if the retriggerable circuit output pulse falls to zero state. Inorder to maintain the pulse output a working system will continue to trigger the retriggerable mono at regular intervals.
But, however, in your applications, you need to switch off/on the power supply itself, you can still do it by applying the output of the watchdog to switch off a MOSFET connected on the negative rail of the supply, may be the ground to watchdog circuit should be connected directly to the -ve lead of the supply to ensure that it will still get supply when the instrument is switched off. Alternatively you can also set up a chain of counters using CD4060 to count for long delays and on overflow, trigger a monoshot to disconnect the supply. In any case if you are switching off the supply, you have to generate sufficiently long pulse to ensure that your instrument is fully switched off before it is switched on again.
Regards,
Laktronics

Re: long range reset ic

solid state relay is an electronic relay (non electromagnetic) using triac which can control ac power load using dc current with low voltage