Hi All
I have a simple circuit. An LM7815AC and a LM7805C Regulator. They are connected to a micro puck 2009 in a Buck/boost driver configuration as shown in the pic. I have also included links to the regulators and the Cree.
Please can someone take a look at this for me as the LM7815AC gets very hot and when testing the micro puck burnt out and now fails. I have a bench supply and drove the voltage from 26V to 29V. The mAh shown on the supply remained <400mAh during this period.
1) I know this is going straight over my head due to my lack of training in electronics but can someone explain what's going wrong please.
2) The end result is that I want to be able to connect the headlight to a 27V battery. The headlight is normally powered by a 3.7V battery and the micro puck works well at this Volatage. I would like to create a small module so that if the battery goes flat I can then connect the headlight up to the larger battery as an emergency power source. The V in, will have to be dropped to <5V due to the micro puck and other electronics in the headlight (ie 08M2 Picaxe) so as to emulate the voltage from the 3.7V battery. Can you please suggest a way I can achieve this.
Thanks for looking and I appreciate your help in advance.
I have a simple circuit. An LM7815AC and a LM7805C Regulator. They are connected to a micro puck 2009 in a Buck/boost driver configuration as shown in the pic. I have also included links to the regulators and the Cree.
Please can someone take a look at this for me as the LM7815AC gets very hot and when testing the micro puck burnt out and now fails. I have a bench supply and drove the voltage from 26V to 29V. The mAh shown on the supply remained <400mAh during this period.
1) I know this is going straight over my head due to my lack of training in electronics but can someone explain what's going wrong please.
2) The end result is that I want to be able to connect the headlight to a 27V battery. The headlight is normally powered by a 3.7V battery and the micro puck works well at this Volatage. I would like to create a small module so that if the battery goes flat I can then connect the headlight up to the larger battery as an emergency power source. The V in, will have to be dropped to <5V due to the micro puck and other electronics in the headlight (ie 08M2 Picaxe) so as to emulate the voltage from the 3.7V battery. Can you please suggest a way I can achieve this.
Thanks for looking and I appreciate your help in advance.
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