Hello Dick,
Sorry for the late reply, I just check you already reply me.
1) You said that if a TLC is being driven a another TLC a pull up is not needed. Do you know if there is any distance constraint? My application will use 16 TLC but in 4 groups of 4 TLC, each group will interconnect between each other but I am estimating that the trace length between the SDO of one group to the SDI of the following one will be near 60 or 70 centimeters.
2) I am using a Microchip MCU, the spec file says each I/O can sink 20mA. For a normal configuration it should be more than enough, but since I am using 16 TLC5927 plus all the PCB traces I am not sure if such current will be enough.
Best regards
Mark