TLC5941NT datasheet by Texas Instruments

TLC5941NT Frequently Asked Questions (FAQs)

• What is the maximum frequency of the clock input?
  The maximum frequency of the clock input is 30 MHz, but it's recommended to keep it below 20 MHz for reliable operation.
• How do I properly sequence the GSCLK, SCLK, and XLAT signals?
  The recommended sequence is: GSCLK low, SCLK low, XLAT high, then GSCLK high to latch the data. After that, SCLK can be clocked to transfer data, and XLAT can be low to update the outputs.
• What is the purpose of the XLAT pin, and how does it differ from the BLANK pin?
  The XLAT pin is used to latch the grayscale data into the output registers, while the BLANK pin is used to blank the outputs (set them to a high-impedance state). XLAT is typically used in conjunction with GSCLK to update the outputs, whereas BLANK is used to turn off the outputs during refresh periods.
• How do I calculate the maximum current per channel?
  The maximum current per channel depends on the VCC voltage and the RSET resistor value. The formula is: IOUT(max) = VCC / (RSET * 32). For example, with VCC = 5V and RSET = 1.2kΩ, IOUT(max) = 5V / (1.2kΩ * 32) = 13.0mA.
• What is the recommended value for the RSET resistor, and how does it affect the output current?
  The recommended value for RSET is between 1kΩ and 4.7kΩ. A smaller RSET value results in higher output current, but also increases power consumption and heat generation. A larger RSET value results in lower output current, but reduces power consumption and heat generation.