My eventual goal is to have 4 TLC5940s controlling 64 digital microservos. I had two TLC5940 breakout boards (Sparkfun) daisychained, with a 5V adapter connected to the first board. This worked well with a handful of servos responsive on both boards.
However, after about a day of experimenting and moving up to about 6 servos on one board, I apparently burnt the first board out. The breakout board includes 2.2k resistors for each output and a 2.2k resistor on the lref pin. Wondering if using thermal tape to attach a heat sink to the TLC5940 would be a means to reduce this heating.
Any pointers in the right direction as far as approach is concerned would be greatly appreciated, thanks.
You must be passing servo power thru the board. It may not handle a high current of multiple servos. A heat sink is irrelevant. The chip should be ok unless you badly miswired the board. The main servo power is thru the V+ lines not thru PWM which is only a logic signal. More likely you burned a circuit trace which acted as a unintended fuse. The board is primarily intended as an LED driver. There are better choices for servo controllers. For example:
You can also control many servos directly from an arduino using counters:
The breakout board includes 2.2k resistors for each output
That is odd do you know why?
A link to the board would be good along with how you wired it up.
Did the board ever feel hot or did it just stop working?
A thermal gel pad can be used to couple the chip to a heatsink if heat is a problem, but that will only get you so far. What dissipation did you calculate. The formular is in the data sheet.
Thanks for the link.
I can't see how connecting the control line to a servo to those outputs can possible cause overheating. I think the OP must have done something else to kill it.