Hi Folks,
I am looking for your feedback on a circuit protection methodology for a LED driver circuits using a BCR321 constant current driver.
The LED array that gets connected to this circuit has exposed solder points, and they frequently get shorted to an instrument housing which destroys the LED driver and also seems to cause random damage to the micro controllers (Atmel Xmega128A3U) that is driving the PWM to the BCR321.
I had two ideas for providing some protection.
1. Adding a forward diode on the PWM line to prevent any current flowing back to the micro.
2. Adding a current limiting resistor (fusistor) in line on the power side of the BCR321 where it is driving the LED array.
What are your thoughts?
Do you think that adding a forward diode on the PWM line will provide protection and will it interfere with my PWM signal.
Do you think that adding a passive component like a fusistor on my PWM output will effect these the LED array?
I have attached a schematic of the LED driver circuit. Signal LED_TOP is the PWM connected directly to the Microcontroller pin.
The BAS3007A is in place to provide reverse polarity protection and is exactly as specified in the BCR321 app note.
The PWM from the MCU is running at 15.85KHz
Looking forward to any feedback or suggestions you may have.
Many thanks
A.
I am looking for your feedback on a circuit protection methodology for a LED driver circuits using a BCR321 constant current driver.
The LED array that gets connected to this circuit has exposed solder points, and they frequently get shorted to an instrument housing which destroys the LED driver and also seems to cause random damage to the micro controllers (Atmel Xmega128A3U) that is driving the PWM to the BCR321.
I had two ideas for providing some protection.
1. Adding a forward diode on the PWM line to prevent any current flowing back to the micro.
2. Adding a current limiting resistor (fusistor) in line on the power side of the BCR321 where it is driving the LED array.
What are your thoughts?
Do you think that adding a forward diode on the PWM line will provide protection and will it interfere with my PWM signal.
Do you think that adding a passive component like a fusistor on my PWM output will effect these the LED array?
I have attached a schematic of the LED driver circuit. Signal LED_TOP is the PWM connected directly to the Microcontroller pin.
The BAS3007A is in place to provide reverse polarity protection and is exactly as specified in the BCR321 app note.
The PWM from the MCU is running at 15.85KHz
Looking forward to any feedback or suggestions you may have.
Many thanks
A.
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