SNVU871 june   2023

 

  1.   1
  2.   Description
  3.   Get Started
  4.   Features
  5.   Applications
  6.   6
  7. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  8. 2Hardware
    1. 2.1 Hardware Setup
  9. 3Software
    1. 3.1 Software Setup
    2. 3.2 Graphical User Interface (GUI) Guidance
      1. 3.2.1 Start Page
      2. 3.2.2 Home Page
      3. 3.2.3 LED Control Page
      4. 3.2.4 Pattern Page
      5. 3.2.5 Register Map Page
  10. 4Hardware Design Files
    1. 4.1 Schematic
    2. 4.2 PCB Layout
    3. 4.3 Bill of Materials
  11. 5Additional Information
    1.     Trademarks

3.2.3 LED Control Page

Set the color and brightness for every RGB LED pixel in the LED control page. To illuminate one LED with default configuration, use the following procedure and see Figure 3-5.

  1. Click the Enable button to enable the LP5860T in the software.
  2. Select the LED the user wants to control.
  3. Set a color for this LED.
  4. Click the Set Brightness button to upload PWM value into the device.
  5. Click the VSync button to active this LED (The default is Mode 3 so the SYNC signal is necessary).
GUID-20221124-SS0I-FMLW-ZN8N-CN0XRG5QBQXR-low.svg Figure 3-7 LED Control Page and Test Procedure

Device Configuration

To improve performance under different applications, configure the key settings first. Select the DEVICE CONFIGURATION button to show the detail setting slide, which is illustrated in Figure 3-6. Maximum current (MC) is set here. Please note: if LP5860T is under test, then the Global Maximum Current setting must be: 7.5mA, 12.5mA, 25 mA, 37.5mA, 50 mA, 75 mA, and 100 mA related to first 6 buttons (000 - 110 for bit3 - bit1 in Dev_config3 register) under Global Maximum Current setting. Therefore, if 15 mA is chosen on the Device Configuration page, then the actual value for LP5860T maximum current is 37.5mA. If a high maximum current is set, then an external VLED supply is recommended. The Data Refresh Mode settings determine whether a SYNC signal is required to synchronize the PWM change for every LED dot. The Max Scan Lines controls select how many scan lines are active. For more information on the functions for other settings, see the LP5860T 11 × 18 LED Matrix Driver with 8-bit Analog and 8-, 16-bit PWM Dimming Data Sheet.

When evaluating matrix-issue free performance, de-ghosting and low brightness compensation are configured here.

GUID-20210505-CA0I-RGV6-WXQK-VSNQMGMJJSNC-low.svg Figure 3-8 Device Configuration

Custom LED Setting

Before setting color and brightness for RGB LED, one or multiple LEDs (Shift + select for multiple LED selections) must first be selected. In the CUSTOM tag, set the color in color selector on the right side, see Figure 3-7. Brightness is used to adjust the PWM for all 3 dots in one RGB LED. For some high requirement applications, dot current can adjust white balance for every RGB LED.

GUID-20210505-CA0I-4HMP-VHLR-QG9FC8HJCVVB-low.svg Figure 3-9 Custom Setting

Global and Group Setting

Figure 3-8 illustrates the GLOBAL tab where color current for RGB groups and global PWM for all LED dots are set. Figure 3-9 illustrates the GROUP tab where every LED dot can be configured to 3 groups arbitrarily, while the PWM for the same group can be changed synchronously.

GUID-20210505-CA0I-JKSK-DVS7-63Q8GTFSWSWT-low.svg Figure 3-10 Global Setting
GUID-20210505-CA0I-WMDG-LBTD-BGKT29GGZ8PB-low.svg Figure 3-11 Group Setting

Fault Detection

The LP5860T continually detects the status for every LED dot. Once an open or short failure is detected, the fault status is also be monitored on the GUI. Clicking the warning bar near an abnormal LED shows the fault details, as illustrated in Figure 3-10. Clicking the fault summary at the right-top of the GUI shows the summary for all fault status (see Figure 3-11). The Clear Short LED and Clear open LED buttons are used to clear related fault flags when the failures are removed.

To have precise detection results, the current for every LED dot must be set above 0.5 mA and the PWM must be set above 25%, due to the parasitic capacitor induced from the LED matrix. A current that is too small leads to abnormal LSD results.

GUID-20210505-CA0I-QZNT-TC1N-0LZJQPB4L3TT-low.svg Figure 3-12 Single Fault Alarm
GUID-20210505-CA0I-MDQG-8V4N-NX0RXD0XBFLM-low.svg Figure 3-13 Total Fault Summary