I am new and beginner in the design of SMPS used for battery chargers and hence I would like to make use as reference to the applications notes found
in TI website (listed in below atachments, i.e. SLVA437–September 2010 and Application Note U-166) to design and implement a battery charger for the
following lead-Acid (GEL,AGM) marine batteries.
Set AGM batteries 12V/70A , 12V/225A
Set gel batteries 12V/55A 12V/200A
Set gel batteries 2V/280A & 2V/580A
Is it fine if I follow the theorietical Steps described in the Application notes for ICs bq24650 and UC3909 so to implement a battery charger for the above lead-acid batteries?This should be an offline battery charger.
Thanks in advance for your Support and feedback.
6052.IMPLEMENTING MULTI-STATE CHARGE ALGORITHM WITH THE UC3909.pdf
4263.Using the bq24650 to Charge a Sealed, Lead-Acid Battery.pdf
For most lead-acid batteries, "exercising" the battery with pulsing currents during the constant voltage phase of the chage profile maximizes battery life. However, each lead acid battery manufacturer should provide a recommended charging profile for their battery. If the profile in the referenced application notes applies to your batteries then you should be able to use the circuits in the application notes.
Thanks for your reply.But what about the maximum charging current? It seems that BQ26450 supports a maximum current of 10Amp.Is that right?For higher power or current applications I can make use of the same schematics as shown in the documents but to have more charging current I will need to use two chargers using the BQ26450 IC.Is that right ?
Does the UC3909 has the same limitation?
Note that I will be using AC power through bridge rectifier to convert to DC Voltage and not solar panel.
Thanks again for your great support and feedback.
Further to the below mail which IC you suggest to use i.e. which is the most simplest to use concerning design and implementation for the mentioned application.
Is it the UC3909 or the BQ26450 IC.
Thanks again for you reply .
For the bq24650, the 10A limitation is primarily a function of the external FETs chosen. The bq24650 HIDRV and LODRV provide a fixed amount of gate drive to the FETs. The FETs that were available on the market when the this IC was developed had such a high gate charge that the HIDRV and LODRV outputs had difficulty driving them to provide more than 10A. It is my understanding that newer (probably more expensive) FETs are now available with lower gate charge. Therefore, it may be possible for the bq24650 HIDRV and LODRV pins to drive these FETs up to 20A. A safer approach would be to add dedicated gate drive ICs (essentially buffers) in between the HIDRV and LODRV pins and the gate of each FET. The UC3909 will have a similar limitation.
The bq24650 with additional gate drive FETs will be simpler than the UC3909.
Where I can download the Mathcad utility software to calculate the component values needed for the lead acid battery charger as described in U-155 Application Note for UC3909 device.
Thanks again for your great support.
You can get a free 30-day trial of MathCAD at http://www.ptc.com/community/free-downloads.htm.
Curious. The answer does not fit the question. I have a copy of MathCad 15 on my work computer, as well as my home PC. As the person asked, where and/or how can one download the MathCad file referred to in U-155. Since the application note is in PDF, one cannot simply copy the math from the app note and paste it into MathCad. You have to type in all the formulaes by hand. It's very tedious and shouldn't be necessary since Mr. Balogh and company have already gone through that exercise.
Thanks. We would all appreciate an appropriate answer.
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with respect to these materials. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.