power-consumption question/issue

Archiver

I've built a simple circuit on the SuperCarrier board. My power
source is a 9Volt Alkaline duracell that's attached to the batter-
receptacle on the board. The circuit is built around the BS2.

The circuit consists of a single ADC0831CCN chip that monitors an
input device's voltage. When this voltage increases momentarily from
1.27V to 1.99V, I begin a brief transmission over the BS2 serial
port. (A total of 3 send/receives.)

The circuit operates as expected with one exception, the 9V battery
is drained in a few short hours. (When I check the board after
running overnight, the green LED on the SuperCarrier board is no
longer lit. In addition, the battery registers 6.8V on a multimeter.)

I've tried inserting both SLEEP and NAP commands in my code in hopes
of increasing battery-life; however, these commands appear to be of
little/no-consequence.

Does anyone have any tips regarding how I should go about
troubleshooting the circuit to determine why I'm depleting the
battery so rapidly? (Also, would I prolong battery life if I
bypassed the LM2940 on the Super Carrier board? (If memory serves,
there's a voltage regulator on the BS2 as well...))

Thanks,
--Donn

Archiver

I would get rid of the LED as it will eat your 9V pretty fast. You
could also use a low dropout linear regulator to utilize as much as
you can out of your battery. A switching regulator would be more
efficient than a linear regulator. Look at National Semiconductors
Simple Switchers for a simple, easy to use switching regulator. They
have software that will practically design the circuit for you based
on your voltage and current requirements. Would it be possible to use
a wall adapter?

9 volt batteries are pretty wimpy as far as current output goes. Can
you use 6 AA instead if the 9 V?

Jason

--- In basicstamps@yahoogroups.com, "donnmoidaho" <donnmo@l...> wrote:
> I've built a simple circuit on the SuperCarrier board. My power
> source is a 9Volt Alkaline duracell that's attached to the batter-
> receptacle on the board. The circuit is built around the BS2.
>
> The circuit consists of a single ADC0831CCN chip that monitors an
> input device's voltage. When this voltage increases momentarily
from
> 1.27V to 1.99V, I begin a brief transmission over the BS2 serial
> port. (A total of 3 send/receives.)
>
> The circuit operates as expected with one exception, the 9V battery
> is drained in a few short hours. (When I check the board after
> running overnight, the green LED on the SuperCarrier board is no
> longer lit. In addition, the battery registers 6.8V on a
multimeter.)
>
> I've tried inserting both SLEEP and NAP commands in my code in
hopes
> of increasing battery-life; however, these commands appear to be of
> little/no-consequence.
>
> Does anyone have any tips regarding how I should go about
> troubleshooting the circuit to determine why I'm depleting the
> battery so rapidly? (Also, would I prolong battery life if I
> bypassed the LM2940 on the Super Carrier board? (If memory serves,
> there's a voltage regulator on the BS2 as well...))
>
> Thanks,
> --Donn

Archiver

Donn,

Hook up an ammeter and see where the current is being consumed. See what
difference the nap commands are making. Disconnect stuff and see what
happpens. I am not sure about the carrier board, but you don't want two
Vregs, that's for sure. LEDs use juice, may not want that one a battery
powered device. There are also lower power consumption regulators. Check out
Maxim for one, and they send free samples. With a battery only power supply,
you can even just use zener diodes, or at least I have done that with PICS.

Jonathan

www.madlabs.info

---

Original Message

---

From: "donnmoidaho" <donnmo@l...>
To: <basicstamps@yahoogroups.com>
Sent: Monday, March 17, 2003 6:51 PM
Subject: [noparse][[/noparse]basicstamps] power-consumption question/issue


> I've built a simple circuit on the SuperCarrier board. My power
> source is a 9Volt Alkaline duracell that's attached to the batter-
> receptacle on the board. The circuit is built around the BS2.
>
> The circuit consists of a single ADC0831CCN chip that monitors an
> input device's voltage. When this voltage increases momentarily from
> 1.27V to 1.99V, I begin a brief transmission over the BS2 serial
> port. (A total of 3 send/receives.)
>
> The circuit operates as expected with one exception, the 9V battery
> is drained in a few short hours. (When I check the board after
> running overnight, the green LED on the SuperCarrier board is no
> longer lit. In addition, the battery registers 6.8V on a multimeter.)
>
> I've tried inserting both SLEEP and NAP commands in my code in hopes
> of increasing battery-life; however, these commands appear to be of
> little/no-consequence.
>
> Does anyone have any tips regarding how I should go about
> troubleshooting the circuit to determine why I'm depleting the
> battery so rapidly? (Also, would I prolong battery life if I
> bypassed the LM2940 on the Super Carrier board? (If memory serves,
> there's a voltage regulator on the BS2 as well...))
>
> Thanks,
> --Donn
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
>