Voltage Conversion - UP
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Is there a decent circuit to be had that will allow me to make a 12v 20 Ah
battery supply (safely and smoothly) 14v at some still respectable current?
I have a robot that has a pair of 12v battery supplies, but I'd like to step
the upper electronics lines to 14v and then regulate them down to 12v again
for line stability.
I have video and audio circuits that are voltage sensitive and I'd rather
spend the batteries capabilities quicker at a higher voltage than deal with
the noise of 11.5v or so over a longer period. The motors are on the second
battery and aren't voltage sensitive, so my current requirements are
probably under 1500 mA.
Hopefully I have made my goal clear. (°;
TIA!
---
Jeff Abrams
clavier@b...
SUPERCHARGED & INTERCOOLED 2.5 liter 1993 Mazda MX-3 GS
http://www.mazdamaniac.com
TURBOCHARGED & INTERCOOLED 1.8 liter 1997 Mazda MX-5 Miata
A PBS mind in an MTV world.
battery supply (safely and smoothly) 14v at some still respectable current?
I have a robot that has a pair of 12v battery supplies, but I'd like to step
the upper electronics lines to 14v and then regulate them down to 12v again
for line stability.
I have video and audio circuits that are voltage sensitive and I'd rather
spend the batteries capabilities quicker at a higher voltage than deal with
the noise of 11.5v or so over a longer period. The motors are on the second
battery and aren't voltage sensitive, so my current requirements are
probably under 1500 mA.
Hopefully I have made my goal clear. (°;
TIA!
---
Jeff Abrams
clavier@b...
SUPERCHARGED & INTERCOOLED 2.5 liter 1993 Mazda MX-3 GS
http://www.mazdamaniac.com
TURBOCHARGED & INTERCOOLED 1.8 liter 1997 Mazda MX-5 Miata
A PBS mind in an MTV world.
Comments
series this would et you 12.6 (assuming a lead acid battery) + 2.4
volts. Is that close enough? The current requirements are in line. A
'D' size rechargeable Nicad could easily handle 1500 MA..
regards,
Leroy
Jeff Abrams wrote:
>
> Is there a decent circuit to be had that will allow me to make a 12v 20 Ah
> battery supply (safely and smoothly) 14v at some still respectable current?
> I have a robot that has a pair of 12v battery supplies, but I'd like to step
> the upper electronics lines to 14v and then regulate them down to 12v again
> for line stability.
> I have video and audio circuits that are voltage sensitive and I'd rather
> spend the batteries capabilities quicker at a higher voltage than deal with
> the noise of 11.5v or so over a longer period. The motors are on the second
> battery and aren't voltage sensitive, so my current requirements are
> probably under 1500 mA.
> Hopefully I have made my goal clear. (°;
>
> TIA!
>
> ---
>
> Jeff Abrams
> clavier@b...
>
> SUPERCHARGED & INTERCOOLED 2.5 liter 1993 Mazda MX-3 GS
> http://www.mazdamaniac.com
> TURBOCHARGED & INTERCOOLED 1.8 liter 1997 Mazda MX-5 Miata
>
> A PBS mind in an MTV world.
>
> To UNSUBSCRIBE, just send mail to:
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of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
take part of that and clean it up? Putting cells in series as one list member
suggested would work, but you might find it tricky getting the capacities
matched such that all your batteries give you the same life. In other words, do
you care if you're always replacing the D batteries but not the others?
I would look at DC/DC converters. They're all over the net, so you should be
able to find the capacity (amps) and price that fits your needs. Good luck.
Clark Hughes
Jeff Abrams wrote:
>
> Is there a decent circuit to be had that will allow me to make a 12v 20 Ah
> battery supply (safely and smoothly) 14v at some still respectable current?
> I have a robot that has a pair of 12v battery supplies, but I'd like to step
> the upper electronics lines to 14v and then regulate them down to 12v again
> for line stability.
> I have video and audio circuits that are voltage sensitive and I'd rather
> spend the batteries capabilities quicker at a higher voltage than deal with
> the noise of 11.5v or so over a longer period. The motors are on the second
> battery and aren't voltage sensitive, so my current requirements are
> probably under 1500 mA.
> Hopefully I have made my goal clear. (°;
>
A 12V lead acid battery will typically stay at about 13 volts through
most of its discharge curve. As for stability, a battery of 20 Ah has a
low internal impeadence . DC-DC converters by their nature are noisy. If
you're worried about volt drop down cables and noise affecting control
circuits. Separate the control circuit cabling from the power circuit.
As for adding "unmatched" cells to a battery, this can cause problems as
the battery discharges. In fact you can get cell polarity reversal.
Rob
Original Message
From: Jeff Abrams [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=Z5mppbCa_RE8Z9Yti-6zB2M0DP0FGMp4_CmHIW_ZOCwO2KpNtws4GTtOqYUDEmac1fPrz76kC3B2NbcZox8khvk]clavier@b...[/url
Sent: 28 March 2002 19:47
To: Basicstamps@Yahoogroups. Com
Subject: [noparse][[/noparse]basicstamps] Voltage Conversion - UP
Is there a decent circuit to be had that will allow me to make a 12v 20
Ah
battery supply (safely and smoothly) 14v at some still respectable
current?
I have a robot that has a pair of 12v battery supplies, but I'd like to
step
the upper electronics lines to 14v and then regulate them down to 12v
again
for line stability.
I have video and audio circuits that are voltage sensitive and I'd
rather
spend the batteries capabilities quicker at a higher voltage than deal
with
the noise of 11.5v or so over a longer period. The motors are on the
second
battery and aren't voltage sensitive, so my current requirements are
probably under 1500 mA.
Hopefully I have made my goal clear. (°;
TIA!
---
Jeff Abrams
clavier@b...
SUPERCHARGED & INTERCOOLED 2.5 liter 1993 Mazda MX-3 GS
http://www.mazdamaniac.com
TURBOCHARGED & INTERCOOLED 1.8 liter 1997 Mazda MX-5 Miata
A PBS mind in an MTV world.
To UNSUBSCRIBE, just send mail to:
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I have a robot with two distinct power sources, both of which are 12v 7.2 Ah
SLAs.
The motors are on one battery and I am not bothered by the sag there.
However, the video and audio circuits are on the other battery and if they
see even .2v or so below 12v they act funny.
Typically under load, that battery looks like about 11.7v after 5 minutes of
use. It will stay there for about 2 hours and then drops off.
I would be happy with less battery time if I could have a real stable 12v so
what I am really looking to do is make a power conditioner that will bump
the voltage up to 14v or so and then re-regulate it back down to 12v.
FWIW, I will probably replace the batteries with a single 12v 24 Ah, so the
re-regulation will be even more important since the motors WILL be on that
battery pulling about 6A on there own intermittently.
---
Jeff Abrams
clavier@b...
SUPERCHARGED & INTERCOOLED 2.5 liter 1993 Mazda MX-3 GS
http://www.mazdamaniac.com
TURBOCHARGED & INTERCOOLED 1.8 liter 1997 Mazda MX-5 Miata
If women can have PMS, then men can have ESPN.
Original Message
From: Rob [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=gcwqcROsaNICA6SyvEO57pjVVB0bxvj5mV8bAYzNZbe7nUf8IMD2LcyhN3cUkoh3NERivd7oFXn592fGKk-y-ew]robbed666@b...[/url
Sent: Friday, March 29, 2002 3:24 AM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Voltage Conversion - UP
Hi Jeff,
A 12V lead acid battery will typically stay at about 13 volts through
most of its discharge curve. As for stability, a battery of 20 Ah has a
low internal impeadence . DC-DC converters by their nature are noisy. If
you're worried about volt drop down cables and noise affecting control
circuits. Separate the control circuit cabling from the power circuit.
As for adding "unmatched" cells to a battery, this can cause problems as
the battery discharges. In fact you can get cell polarity reversal.
Rob
that will ensure a solid 12v source?
BEN
Jeff Abrams <clavier@b...> wrote: Let me clarify my intentions:
I have a robot with two distinct power sources, both of which are 12v 7.2 Ah
SLAs.
The motors are on one battery and I am not bothered by the sag there.
However, the video and audio circuits are on the other battery and if they
see even .2v or so below 12v they act funny.
Typically under load, that battery looks like about 11.7v after 5 minutes of
use. It will stay there for about 2 hours and then drops off.
I would be happy with less battery time if I could have a real stable 12v so
what I am really looking to do is make a power conditioner that will bump
the voltage up to 14v or so and then re-regulate it back down to 12v.
FWIW, I will probably replace the batteries with a single 12v 24 Ah, so the
re-regulation will be even more important since the motors WILL be on that
battery pulling about 6A on there own intermittently.
---
Jeff Abrams
clavier@b...
SUPERCHARGED & INTERCOOLED 2.5 liter 1993 Mazda MX-3 GS
http://www.mazdamaniac.com
TURBOCHARGED & INTERCOOLED 1.8 liter 1997 Mazda MX-5 Miata
If women can have PMS, then men can have ESPN.
Original Message
From: Rob [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=oJ7LPeB9zsTRQx3aK7jt2nsKEmPnT98AkxFiRmoBS-Jlp4qDkMETCIvHX2twzU6_7pID2FXZyStONzv93GndaZc]robbed666@b...[/url
Sent: Friday, March 29, 2002 3:24 AM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Voltage Conversion - UP
Hi Jeff,
A 12V lead acid battery will typically stay at about 13 volts through
most of its discharge curve. As for stability, a battery of 20 Ah has a
low internal impeadence . DC-DC converters by their nature are noisy. If
you're worried about volt drop down cables and noise affecting control
circuits. Separate the control circuit cabling from the power circuit.
As for adding "unmatched" cells to a battery, this can cause problems as
the battery discharges. In fact you can get cell polarity reversal.
Rob
To UNSUBSCRIBE, just send mail to:
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the message will be ignored.
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BEN (TEAM DBR)
http://www.geocities.com/temdbr
Do You Yahoo!?
Get personalised at My Yahoo!.
[noparse][[/noparse]Non-text portions of this message have been removed]
inductor in a controlled manor to increase the output voltage to a desired
level.
http://www.national.com/ds/LM/LM2698.pdf
The example shows a 4.5V to 5.5V input providing a 12V 400mA output. The
feedback resistors R1 and R2 can be altered for a different output voltage.
As it was stated earlier DC-DC converters are typically noisy. This
regulator provides two modes of switching frequency 600kHz or 1.25MHz.
I would think that either one would do well for your application.
> Can you use a fancy voltage regulator to bring under 12 back up to
> 12v and that will ensure a solid 12v source?
>BEN
> Jeff Abrams <clavier@b...> wrote: Let me clarify my intentions:
>
>I have a robot with two distinct power sources, both of which are 12v 7.2 Ah
>SLAs.
>The motors are on one battery and I am not bothered by the sag there.
>However, the video and audio circuits are on the other battery and if they
>see even .2v or so below 12v they act funny.
>Typically under load, that battery looks like about 11.7v after 5 minutes of
>use. It will stay there for about 2 hours and then drops off.
>I would be happy with less battery time if I could have a real stable 12v so
>what I am really looking to do is make a power conditioner that will bump
>the voltage up to 14v or so and then re-regulate it back down to 12v.
>FWIW, I will probably replace the batteries with a single 12v 24 Ah, so the
>re-regulation will be even more important since the motors WILL be on that
>battery pulling about 6A on there own intermittently.
>
>---
>
>Jeff Abrams
>clavier@b...
>
>SUPERCHARGED & INTERCOOLED 2.5 liter 1993 Mazda MX-3 GS
>http://www.mazdamaniac.com
>TURBOCHARGED & INTERCOOLED 1.8 liter 1997 Mazda MX-5 Miata
>
>
>If women can have PMS, then men can have ESPN.
>
>
>
>
>
Original Message
>From: Rob [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=-6qm6bi2Q3gsf3vp1GT7AjUDfOnlKlGqFJO4Zg3ZeIh6PgKqSph4xGjSnVEg4Er1E5rmiI5qTteCLUBf7tVKbg]robbed666@b...[/url
>Sent: Friday, March 29, 2002 3:24 AM
>To: basicstamps@yahoogroups.com
>Subject: RE: [noparse][[/noparse]basicstamps] Voltage Conversion - UP
>
>
>Hi Jeff,
>
>A 12V lead acid battery will typically stay at about 13 volts through
>most of its discharge curve. As for stability, a battery of 20 Ah has a
>low internal impeadence . DC-DC converters by their nature are noisy. If
>you're worried about volt drop down cables and noise affecting control
>circuits. Separate the control circuit cabling from the power circuit.
>As for adding "unmatched" cells to a battery, this can cause problems as
>the battery discharges. In fact you can get cell polarity reversal.
>
>Rob
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