LED matrix display experimental circuit board composed of TLD2131

1, LED matrix

  in Test Infineon vehicle LED driver chip TLD2131 The LED driver chip of TLD2131 with 1 in 3 out is preliminarily tested. In order to use fewer MCU IO ports to control more LEDs, LED matrix mode needs to be used. This can take advantage of the high side driving LED characteristics of TLD2132. Therefore, it is convenient to organize the matrix display of LED as long as several NPN triodes are selected at the bottom.

   for N upper output ports and M lower output ports, N can be formed × MLED lattice control. Through cyclic control, the control characteristics for a single LED can be dynamically formed.

2, LED matrix based on TLD2331

  in Infineon's high side LED driver chip series, there are three in three out TLD2331-3EP, and its internal structure is shown in the figure below. Three columns of LEDs can be driven by one TLD2331-3EP, and six columns of LED output can be controlled by two TLD2331. Therefore, when using three NPN triodes, it can form 6 × 3 = 18 led matrices.

   in order to verify the driving characteristics of TLD2331, this paper uses the TLD2131 composition circuit that has just arrived to test.

1, Circuit design 1

  based on three TLD2131 Simulate the high side control of a TLSD2331 and test the characteristics of the circuit.

1. Circuit schematic diagram 1

  three TLD2131 are used to form 3 × The circuit schematic diagram of LED display matrix is as follows:

2. Rapid plate making experiment PCB

   design a single-sided PCB to realize the above schematic diagram, which can be suitable for use One minute plate making Make experimental circuit. The following is the corresponding PCB designed.

3. Welding PCB

   after one minute, PCB is obtained through rapid plate making. After welding, the circuit is debugged in form.

2, Build circuit

1. Build circuit on bread board

  build the test circuit on the bread board. Controller use Design mm32f3277 micro Python experimental board with SD card To control. The control pin distribution is controlled by pc0,1,2,3 and pa0,1. Which downloaded Micropathon from MindMotion version 2021-11 . You can use micro Python to test the corresponding functions.

2. Connection relationship

   the connection relationship between MM32F3277 test circuit board and LED matrix test control port is as follows:

3, Test LED matrix

1. Overall flashing

from machine import Pin import utime row = [Pin('PC%d'%i, Pin.OUT_PUSHPULL) for i in range(3)] col = [Pin('PC3', Pin.OUT_PUSHPULL), Pin('PA0', Pin.OUT_PUSHPULL), Pin('PA1', Pin.OUT_PUSHPULL)] print("Light all LED.\r\n") while True: for r,c in zip(row, col): r(1) c(1) utime.sleep_ms(250) for r,c in zip(row, col): r(0) c(0) utime.sleep_ms(250)

   after the software runs, you can see that all (9) LED s flash at the same time.

2. Water lamp test

from machine import Pin import utime row = [Pin('PC%d'%i, Pin.OUT_PUSHPULL) for i in range(3)] col = [Pin('PC3', Pin.OUT_PUSHPULL), Pin('PA0', Pin.OUT_PUSHPULL), Pin('PA1', Pin.OUT_PUSHPULL)] print("Light all LED.\r\n") ledrow = 0 rowbyte = [7]*3 def LED1ms(): global ledrow, rowbyte, row, col for r,c in zip(row, col): r(0) c(0) rb = 0 if ledrow == 0: ledrow += 1 elif ledrow == 1: ledrow += 1 else: ledrow = 0 row[ledrow](1) rb = rowbyte[ledrow] if rb & 0x1: col[0](1) if rb & 0x2: col[1](1) if rb & 0x4: col[2](1) def SetLEDPoint(id): global rowbyte rowbyte = [0]*3 pp = id//3 p3 = id - pp*3 rowbyte[pp] = 1 << p3 count = 0 position = 0 while True: LED1ms() utime.sleep_ms(1) count += 1 if count >= 50: count = 0 SetLEDPoint(position) position += 1 if position > 8: position = 0

3. Test LED column

  add the SetLEDColumn() function on the basis of the previous test code, and modify the main loop.

def SetLEDColumn(id): global rowbyte rowbyte = [0]*3 for i in range(id + 1): pp = i//3 p3 = i - pp*3 rowbyte[pp] |= 1 << p3 #------------------------------------------------------------ count = 0 position = 0 dir = 0 while True: LED1ms() utime.sleep_ms(1) count += 1 if count >= 50: count = 0 if dir == 0: SetLEDColumn(position) else: SetLEDColumn(8 - position) position += 1 if position > 8: position = 0 if dir == 0: dir = 1 else: dir = 0

  the high side LED driver chips TLD2131 and tld2331 of Infineon company are used to form an LED matrix driving circuit together with NPN transistors, and a small amount of GPIO can be used to drive LED matrix display. In this paper, three TLD2131 are used to form 3 × The working principle of the circuit is tested. It provides a basis for the design of LED lamp column used to display voltage in smart car competition.

1, LED lamp post

  according to The 17th National College Student smart car competition It is required that the wireless charging resistor needs to use LED to display the voltage on the farad capacitor of the current vehicle model. Using the above reference design, it is convenient to design a luminous array composed of LED to display.

  six columns of LEDs can be driven by two TLD2331, and 18 strings of LED display can be controlled with three NPN transistors. Three LEDs in series can increase the width of the array and make the display more eye-catching.

■ links to relevant literature:

• Test Infineon vehicle LED driver chip TLD2131
• TLD2131
• One minute plate making method
• Design mm32f3277 micro Python experimental board with SD card
• Test mm32f3277 micropathon version 2021-11-17
• Racing rules of the 17th National University intelligent vehicle competition

● relevant chart links:

• Figure 1.1.1 LED display matrix
• Figure 1.2.1 internal function diagram of tld2131 (left) and TLD2331 (right)
• Figure 2.1.1 composition of three TLD2131 3 × LED display matrix
• Figure 2.1.2 single sided PCB design produced by rapid plate making process
• Figure 2.1.3 welding experimental circuit board
• Figure 2.2.1 test circuit built on bread board
• Figure 2.3.1 all LED s flashing
• Figure 2.3.2 test the effect of water flow lamp
• Figure 2.3.3 program operation effect
• Figure 3.1 LED matrix with 18 columns of independent control

1. Test circuit board AD project file: AD\Test21\TLD2131\TestTLD2131Mul.PcbDoc* ↩︎ ↩︎

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