Wanted: RF Reciever IC with "Sleep" ability
 

I'm in Automated Home technologies - I need to install a reciever unit (RF -
FCC approved freq.) which will "lay low" and not tax the snot out of
batteries.

For example: Your RC cars which you purchase from WalMart - use a chip that
quickly eats the batteries up.
Cell Phones are polling the stations constantly and tax the batteries up.,

I need an IC that will LAY LOW / SLEEP - perhaps look every 1 second for a
signal and STARTUP at that point. My unit is a simple 4.5V DC operated
motor that I wish to trigger RIGHT/LEFT perhaps only once / month! My unit
is to be installed and the batteries would be a major pain to replace -
would destroy sales of unit.

Cell phones (I would think) should seek this kind of technology - that is,
only "peek" once in a while for the data and sleep the remainder of the
time. But perhaps, Cell Phones have much more "to do" than my simple
application.

I am simply "opening and closing" a small door with a small DC motor. But
my issue is that all the RF Reciever IC's I've investigated are BUZY BUZY -
They eat up a pair of 'AA' batteries in 1 Month with conservative
circuitry - that unaccacceptable for my applicaction.

If anyone knows of an RF Reciever IC that has this "sleep" ability built
in - it would be RADICALLY appreciated !!!!!

What about simple pager units??? Are they "charge me charge me charge
me"???

Why aren''t the engineers considering the "look occasionally for
data/signal" condition instead of constantly looking at the freq: which they
are triggered at?

Best Regards to all
Walt

Investigate Microchip

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Paul

I recently went through one IC with a "Sleep mode" which required an
EXTERNAL PULSE to trigger the sleep mode on/off.

The *BIG* question is: How does "Stand By" become triggered off and on? -
External pulse or through the reciever signal? If through the reciever
signal - all is WAY GOOD , YES. If through some external pulse - then the
"Stand By" mode becomes "senseless" in my mind because one could simply kill
the VCC at that point. Do you know/understand how the "Stand by" mode is
triggered off?

From the description of Pin 28 in the PDF manual it states:
Bias circuitry provides bandgap biasing and circuit
shutdown capabilities. The ENRX (Pin 28) modes are
summarized in Table 2-1. The ENRX pin is a CMOS
compatible input and is internally pulled down to Vss.

TABLE 2-1: BIAS CIRCUITRY CONTROL
ENRX(1) Description
0 Standby mode
1 Receiver enabled
Note 1: ENRX has internal pull-down to Vss

It "appears" (I hope I'm wrong) that an external bias must be applied to Pin
28 to take the IC out of "Sleep mode". In which case - I fail to see its
purpose. I need the IC to be "awaken" via an RF pulse or "trigger freq".


Investigate Microchip

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Paul

Or - I could put a 555 timer on pin 28 and have it On every 1 second -
Hmmm...may work ey?

"loedown" wrote in message
...
Investigate Microchip

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Paul

NO - The timer eats too much Power :( and exhausts the batteries again.

"jack" wrote in message
...
Or - I could put a 555 timer on pin 28 and have it On every 1 second -
Hmmm...may work ey?

"loedown" wrote in message
...
Investigate Microchip


http://www.microchip.com/stellent/id...PAGE&nodeId=74

about 3/4 the way down the page

Paul