TLC5940NTG4 datasheet by Texas Instruments

TLC5940NTG4 Frequently Asked Questions (FAQs)

• What is the maximum frequency of the clock input?
  The maximum frequency of the clock input is 25 MHz, but it's recommended to keep it below 10 MHz for reliable operation.
• How do I ensure that the TLC5940NTG4 is properly initialized?
  To ensure proper initialization, apply a reset pulse to the RST pin, then send a 'mode set' command (0x01) to the device, followed by a 'display enable' command (0x03) to enable the outputs.
• What is the purpose of the GSCLK pin, and how do I use it?
  The GSCLK pin is the grayscale clock input, which is used to update the grayscale data. It should be connected to a clock source with a frequency between 10 kHz and 25 MHz, and should be synchronized with the SCLK pin.
• How do I handle the thermal shutdown feature?
  The TLC5940NTG4 has a built-in thermal shutdown feature that activates when the junction temperature exceeds 150°C. To handle this, monitor the TSD pin, which goes low when thermal shutdown is activated. When this happens, reduce the current or turn off the device to prevent damage.
• What is the recommended layout and routing for the TLC5940NTG4?
  To minimize noise and ensure reliable operation, keep the power and ground traces separate from the signal traces, and use a solid ground plane. Also, place decoupling capacitors close to the device and use a low-ESR capacitor for the VCC pin.