Hi
I'm building a circuit for charging several 12V batteries. The batteries need to be isolated from one another while charging, and charged one at a time, moving onto the next when full.
Circuit discription / Idea: (not complete as I still need to add the 555 circuitry and temp circuit)
A 555 drives a 4017 with a clock pulse every 5 min. This will cause the 4017 to "shift" once with every pulse, the output of the 4017 will drive a transistor (acting as a switch relay) allowing the charge from the alternator to reach the battery and charge it, as the voltage increases the Opamp will go HIGH, into the 4073 AND gate, (the second input is liked to the output of the 4017 for that "charge channel", and the third will come from another Opamp to monitor the temp of the battery), the output from the AND gate will go HIGH and feed through a diode and inverting gate (left out..oops) to the ENABLE of the 4017.
The reason why there is a link from the output of the 4017 to the 2nd input to the AND gate is to only allow the charging battery line to activate the ENABLE on the 4017, otherwise if any of batteries where full it would shop the 4017 from shifting (hope that makes sense).
Questions:
1 - Can I use a transistor to act as a relay, and as it would probably be easier to get a N-Channel, I'll have to switch the Negative rail and common the Positive Rail?
2 - What N-Channel could I use, it will have an 55 Amp alternator connected.
3 - Since the Positive is common on the batteries, I've done the same on the ICs and have used a 7905 on the negative rail to give a regulated output for the "referance voltage" for the Comparator on the Opamps as well as for the powering of the Opamps, 4073, 4017 and the 555.
4 - Protecting the Transistor, Can I just use a diode across the transistor to protect it when the engine is shut down.
5 - I need the circiut the "make before break" on the outputs to the batteries (pervent spikes from the alternator), I was thinking of using a small cap on the feed to the gate of the transistor, holding it on for a second or so while the other transistor activates.
I've just noticed, I need to place and INVERT gate between the ENABLE pin and diodes.... opps
Would this work?
Thanks in advance
I'm building a circuit for charging several 12V batteries. The batteries need to be isolated from one another while charging, and charged one at a time, moving onto the next when full.
Circuit discription / Idea: (not complete as I still need to add the 555 circuitry and temp circuit)
A 555 drives a 4017 with a clock pulse every 5 min. This will cause the 4017 to "shift" once with every pulse, the output of the 4017 will drive a transistor (acting as a switch relay) allowing the charge from the alternator to reach the battery and charge it, as the voltage increases the Opamp will go HIGH, into the 4073 AND gate, (the second input is liked to the output of the 4017 for that "charge channel", and the third will come from another Opamp to monitor the temp of the battery), the output from the AND gate will go HIGH and feed through a diode and inverting gate (left out..oops) to the ENABLE of the 4017.
The reason why there is a link from the output of the 4017 to the 2nd input to the AND gate is to only allow the charging battery line to activate the ENABLE on the 4017, otherwise if any of batteries where full it would shop the 4017 from shifting (hope that makes sense).
Questions:
1 - Can I use a transistor to act as a relay, and as it would probably be easier to get a N-Channel, I'll have to switch the Negative rail and common the Positive Rail?
2 - What N-Channel could I use, it will have an 55 Amp alternator connected.
3 - Since the Positive is common on the batteries, I've done the same on the ICs and have used a 7905 on the negative rail to give a regulated output for the "referance voltage" for the Comparator on the Opamps as well as for the powering of the Opamps, 4073, 4017 and the 555.
4 - Protecting the Transistor, Can I just use a diode across the transistor to protect it when the engine is shut down.
5 - I need the circiut the "make before break" on the outputs to the batteries (pervent spikes from the alternator), I was thinking of using a small cap on the feed to the gate of the transistor, holding it on for a second or so while the other transistor activates.
I've just noticed, I need to place and INVERT gate between the ENABLE pin and diodes.... opps
Would this work?
Thanks in advance