How to drive a 16x16 LED matrix with LED drivers?

Question

Arduino

Requires driving a 16x16 LED matrix (not RGB, just white diodes) with PWM support using TLC5940 drivers (16 PWM channels) using Arduino UNO.
Do I understand correctly that 2 drivers are required, one for columns, the other for rows? And do you need separate food? (LEDs 3mm, 3V, 20mA) and what else may be required for the matrix to work properly?

Answer 1

2 drivers, one for columns, the other for rows - will not work. Let's say the column lines are output on the TLC5940. It closes its outputs to the ground, which means that the lines of the lines must be closed to VCC. This requires 16 P-channel transistors and a shift register to switch them.
The operation algorithm will be as follows:
1) Turn on the 1st line (in the register 1111 ... 1110, the p-channel transistor opens "zero")
2) Transfer the PWM values ​​​​for all pixels of the line to the driver
3) Wait some time
4) Shift the register to include the next line (1111...1101)
5) GOTO 2