Thank you Emrys,
You are correct, this is about a very low power application. As Clemens suggested in his reply, I have been looking for a low voltage comparator and I found the TLV3691 which has an amazingly low operating voltage as well as exceptionally low supply current. Could you please clarify the points raised below?
Does the use of such a device help avoid excessive power consumption when the input signal is slowly evolving close to the +ve and -ve trip points? The time involved may be as long as 30 mins in some instances. Is there any way of minimising power consumption in such a case? If not, I have to review the complete strategy...
Also, contrary to ON Semiconductor and ST Microelectronics (TS880 & NCS2200), the TLV3691 does not provide a plot of current consumption v/s toggling frequency. Any reason? Can I get this information?