How to design a delay of 2ms or more?

[hurb]

My clock frequency is 1MHz, so if I use clock to get 2ms delay, it will certainly take a lot of area. Does anyone have designed a long delay without clock? The accuracy of delay isn't very important.
I try to use a pretty small current (about several nA) to charge a cap to get a rising voltage, then use an invertor or comparator to get the final delayed signal. Now I am not sure whether the so small current can be implemented in IC, and whether there are any circuit to get stable and small current.
If anyone have done the similar work, please give me a hand. Thank you in advance.

 

[zajbanlik]

Hi

well it's not so bad idea to use this clock. You need 11 bit for generating 2.024ms periodical signal. Any analog realisation will take bigger chip area.

Best regards

 

[alvarorahul]

as zajbanlik has said
i think a simple mod-2048 or 11bit counter should do the trick

it will produce a delay of 2.048ms provided ur clock signal is accurate

 

[hurb]

Maybe you are right. Thank you for your reply.

 

[shake2004]

maybe it's the best one