[FAQ] How to master LP589x / TLC698x devices with LED display applications within five minutes?

[Q1]: What are the main differences between LP5891-Q1 / LP5891 / LP5890 / TLC6984 / TLC6983?

From the functional point of view, the main differences between those devices are shown in Figure 1.

[Q2]: How to quickly light up a LED panel with LP589x / TLC698x? Where is the sample code?

An easier and quicker way is using the evaluation module (EVM). Here are the procedures (You can find the links in Table 1):

1. Apply for an EVM online.
2. Prepare the corresponding controller board TMS320F280039C LaunchPad.
3. Download the sample code.
4. Follow the instructions in the TEST SETUP section in the EVM User’s Guide or follow the Sample Code User's Guide.
5. Then you should be able to light up the LED panel on the EVM.
6. You can download the Registers Map Generation Tool. With this tool, you can try altering the settings of configuration registers and generate a configuration header file that can be substituted into the reference code directly.

Table 1 Summary of Useful Links

[Q3]: How to configure the color / brightness / color temperature of the LED panel?

Table 2 shows the basic register settings that configure the brightness, color temperature and color. You can refer to Register Maps section in the datasheet.

[Q4]: How to implement CCSI? Is CCSI compatible with SPI?

• The SCLK needs to be continuous, no matter if there is data on SIN or not.
• There are 2 solutions:
  • Use dedicated resource to implement the CCSI
    
    • For more information on how CCSI is implemented on C2000, you can refer to this application notes - How to Implement Custom Serial Interfaces Using Configurable Logic Block (CLB). Details can be found in section 4 Example B: Using the CLB to Implement a Custom Communication Bus for LED Driver in Lighting Applications.
  • Use Universal Plug-In Augmented Connectivity (UPAC) device such as LP5899-Q1, LP5899, or TLC6989.
    
    • A standard SPI port of the MCU can be used to communicate to the UPAC device.

[Q5]: How to select power supplies VR, VG, VB and VCC?

1. The recommended operating conditions for VCC, VR, VG and VB should be in the range of 2.5V to 5.5V.
2. Great attention should be paid to LED supply voltage, VR, VG and VB. They should not be too large in order to reduce power consumption inside the chip. Also, they should not be too small to satisfy the knee voltage requirements for the current sources to function well. A simplified output stage of LP589x / TLC698x is illustrated in Figure 2. You can calculate the theoretically minimal VR value with the formulas listed in the figure notes. The same calculating method applies to VG and VB. For all the channels, V_CS should be larger than V_KNEE. You can find the V_KNEE and R_DS(ON) from the Electrical Characteristics section in the datasheet.

[Q6]: Could you provide more relevant resources for LP589x / TLC698x?

Other resources:

• TLC6983EVM promotion video:
• Demo video: link to be added
• To be updated :)