TLC5947 and ULN2803, will it work?

Question

Electronics

Hello! There is a need to control 24 miniature vibration motors. The choice fell on the 24-channel LED driver TLC5947 and ULN2803. Will the TLC5947 be able to drive the PWM signal of the ULN2803 without extra transistors as shown in the schematic?
As far as I know, there is already a similar working version on PCA9685, but they also write on the forums that for proper operation, you need to add another PNP transistor https://forums.adafruit.com/viewtopic.php?f=24&t=6...

Answer 1

ULN2803 will not work, because it requires that the current "flow" into it and, accordingly, "leak" from the source.
and the TLC5947, on the contrary, forms a "flowing" current into itself.
Accordingly, for communication you need either a darlington on PNP or a connection like on https://forums.adafruit.com/viewtopic.php?f=24&t=6...

Answer 2

You don't need to add transistors. But with resistors of the order of several kOhm, it is necessary to pull up the outputs of the TLC5947 to the supply voltage. Then it will work.