Just a quick query, I have designed a quick schematic (see attached) for a power supply.
I needed it to deliver somthign like 1a at 9v output total with the ability to charge a 1.5ah 12 battery so that when AC is not around the battery will take over. I supose it could eb classed as a UPS circuit. I woudl just like your expertise on the circuit before I go ahead and order the relevant components.
My one concern was chargign current, with a 47r resistor, will this be too much/too little to charge the battery. i wanted a current of around 250-300mah and with an aprox charge voltage of 15v, 47 ohms seemed like a good idea.
The BC549 is to ground out the adjust pin of the 317, so that when the battery reached 15v the zener woudl conduct and reduce the output of the first 317 to about 2v, thus stopping charge. This would obviously mean the battery wodul take over powering the output.
The TIP127 is so that when the battery voltage reached just over 10v, the second zener woudl stop conducting and mzke the PNP base positive and cutting the output preventing deep discharge.
Do you think this circuit will suffice or shoudl I make some alterations any where?
Thanks for your aproval,
Jody
I needed it to deliver somthign like 1a at 9v output total with the ability to charge a 1.5ah 12 battery so that when AC is not around the battery will take over. I supose it could eb classed as a UPS circuit. I woudl just like your expertise on the circuit before I go ahead and order the relevant components.
My one concern was chargign current, with a 47r resistor, will this be too much/too little to charge the battery. i wanted a current of around 250-300mah and with an aprox charge voltage of 15v, 47 ohms seemed like a good idea.
The BC549 is to ground out the adjust pin of the 317, so that when the battery reached 15v the zener woudl conduct and reduce the output of the first 317 to about 2v, thus stopping charge. This would obviously mean the battery wodul take over powering the output.
The TIP127 is so that when the battery voltage reached just over 10v, the second zener woudl stop conducting and mzke the PNP base positive and cutting the output preventing deep discharge.
Do you think this circuit will suffice or shoudl I make some alterations any where?
Thanks for your aproval,
Jody
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