CXLC89109 is a memory-mapped LCD driver chip that supports two mainstream display modes: 20 × 4 dot matrix (20SEG × 4COM) and 16 × 8 dot matrix (16SEG × 8COM). The chip has a maximum of 20 × 1 or 16 × 1 matrix key scanning circuit and an I² C two-wire communication interface, greatly simplifying the connection between the main control MCU and the LCD module. Its wide operating voltage range is 2.4V ~ 5.5V, and it is manufactured by CMOS technology. It has both low power consumption and high anti-interference capability, and is suitable for all kinds of harsh industrial environments.
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[ CXLC89109 ]"
CXLC89109 LCD driver chip: high-performance I² C interface, support multi-mode display and key scan function
In today's intelligent and digital industrial control and consumer electronics field, liquid crystal display (LCD) module, as an important component of human-computer interaction, the performance of the driver chip directly determines the stability of the display and the energy efficiency of the system. CXLC89109 is a high-performance driver chip designed for multi-scene LCD applications. With its flexible display mode, efficient key scanning function and simple I² C communication interface, it has become an industrial instrument, ideal for digital clock, counter, voltmeter and other equipment. This paper will deeply analyze the core characteristics, electrical parameters, application circuits and instruction systems of CXLC89109 to help engineers better select and integrate the chip.
I. Overview of chips
CXLC89109 is a memory-mapped LCD driver chip that supports two mainstream display modes:20 × 4 dot matrix (20SEG × 4COM)And16 × 8-point array (16SEG × 8COM). Maximum built-in chip20 × 1Or16 × 1Matrix key scanning circuitI² C two-wire communication interface, greatly simplifies the connection between the main control MCU and the LCD module. Its working voltage range is as wide2.4V ~ 5.5V, manufactured by CMOS technology, it has both low power consumption and high anti-interference capability, and is suitable for all kinds of harsh industrial environments.
II. Features of core functions
2.1 Multi-mode display support
CXLC89109 the display mode can be flexibly switched according to system requirements:
• 20 × 4 mode: 1/3 Bias (Bias),1/4 Duty cycle (Duty)
• 16 × 8 mode: 1/4 bias, 1/8 duty cycle
Both modes are configured through internal instructions without external hardware adjustment, which greatly improves the adaptability and scalability of the system.
2.2. Integrated key scanning function
Maximum built-in chip20 × 1Or16 × 1Matrix keyboard scanning circuit supports hardware interrupt output (INT), which can realize real-time response of button events. Key scan input and segment output pins are reused to effectively save pin resources.
2.3. Low power consumption design
• The static current is as low1μA@3V(Power saving mode)
• Supports external clock and internal RC oscillator.
• Software standby mode to further reduce system power consumption
2.4. Built-in display RAM
Chip Integration16 × 8-bit display data RAM, supports the automatic address increment function to facilitate the master to quickly refresh the display content.
III. Electrical characteristics and interface specifications
3.1. Power supply and working conditions
• Operating voltage:2.4V ~ 5.5V
• Operating temperature:-40 ℃ ~ 85 ℃
• Encapsulation:SOP28
3.2. I² C communication interface, data transmission time waveform
• Supports standard I² C protocol with the highest clock frequency.400kHz
• The slave address is fixed1110 011 R/W
• Supports byte write, page write, and continuous read operations.
Precautions when power on
When the chip is powered on, the internal and reset potential of the chip will be in an unstable low voltage area for a period of time. Due to the power of VDD
When the pressure rises, the chip content is not completely reset, and such misoperation may occur. This prevents this from happening, additional
POR circuit and software reset function are provided. In order to ensure normal internal reset of the chip, the following conditions must be met when power on.
In order to make POR circuit work, it is necessary to meet the recommended conditions of tR tF tOFF and Vbot.
3.3. Driving capability
• COM port pull/fill current typical value180μA@5V
• SEG Port Drive capability is moderate, suitable for a variety of LCD panels
• INT pin supports high and low levels and is compatible with different interrupt logic.
3.4. Input and output equivalent circuit
3.5. Limit parameters
(1) if the chip works for a long time under the above limit parameter conditions, the reliability of the device may be reduced or permanently damaged.
We recommend that you use any parameter to reach or exceed these limits.
(2) all voltage values are tested systematically.
3.6. Recommended working conditions
3.7. DC electrical characteristics
3.8. AC electrical characteristics
3.9. AC AC characteristics
IV. Typical application circuit
CXLC89109 supports a variety of practical application scenarios. The following is a brief description of several typical wiring diagrams:
4.1. 20*4 display mode (no INT), 20*4 display mode circuit diagram without INT
All SEG and COM pins directly drive the LCD, and the key scan input is realized through SEG0 ~ SEG19, with external **180kΩ ~ 220kΩ** pull-up resistor.
4.2. 16 × 8 Display mode (with INT), 19*4 display mode circuit diagram with INT
The SEG15/K15/INT pin is configured as an interrupt output for Button event notification MCU, and the rest SEG and COM pins are used to drive the LCD.
4.3. Circuit diagram of 16*8 Display mode without INT
4.4.15*8 Display mode circuit diagram with INT
4.5. Key scan matrix connection
In the 20 × 4 mode, K0 ~ K19 form a 20 × 1 matrix; In the 16 × 8 mode, K0 ~ K15 form a 16 × 1 matrix. All key scan inputs have internal pull-down, and the external needs only simple pull-up to achieve stable detection.
V. Detailed explanation of instruction system
CXLC89109 receives commands through the I² C interface to realize functions such as Mode setting, display control, and key scanning cycle adjustment:
5.1. System Settings command (0x 80H)
• Control chip enters standby or normal mode
• Turn LCD display on or off
5.2. Mode setting command (0xa0h)
• Select Display mode (20 × 4 or 16 × 8)
• Configure INT pin function and effective level
• INT output can be set to active low or active high.
5.3. Key scan cycle setting command (0 xF8H)
You can adjusting key scan cycles based on LCD load characteristics to avoid reading errors caused by excessive RC constants.
5.4. System oscillator
Both the internal logic and CXLC89109 LCD drive signals are timed by an internally integrated RC oscillator. After the system is initially powered on, the system oscillator is in the stopped state.
5.5.LCD bias generator
VLCD full-scale voltage (VOP) ranges from VDD to VSS. VLCD bias voltage is three from the connection between VLCD and VSS
The internal bleeder of the series resistor is obtained (this VLCD has been connected to VDD inside the chip and cannot be adjusted). Resistance can be opened through different
Switch off to provide 1/4 bias at 1/8 duty cycle or 1/3 bias at 1/4 duty cycle.
5.6. Segment driver output
LCD driver part includes segment output, segment output should be directly connected to LCD display panel. In accordance with the multiplexing column signal and in the display
The latched data resides to generate segment output signals. The unused segment output must remain open.
5.7. Shared drive output
The LCD driving section includes a column output that connects it directly to the LCD panel. The shared input is generated according to the selected LCD drive mode.
Output signal. The output of unused columns should remain open.
5.8 display memory-RAM structure
The RAM that stores data is a static 16 × 8-bit RAM memory. Logical "1" in RAM bit mapping means "on"
The status of the corresponding LCD segment; The same logic 0 indicates the status of "off", and the RAM address and segment output are one-to-one correspondence, and
The output of each RAM byte and the column is also a one-to-one correspondence. The following table shows the mapping from RAM to LCD mode:
VI. Application field recommendation
CXLC89109 is widely used in:
• Industrial control panel: status indication and parameter display
• Intelligent instrument: voltmeter, counter, thermometer
• Consumer electronics: digital clock, home appliance display module
• Medical equipment: portable testing instrument reading screen
VII. LCD drive mode waveform
7.1 20*4 display mode, 1/4 duty , 1/3 bias
7.3.2. Hardware interrupt function is optional, allowing SEG19/ COM4/ K19/ INT to be used in 20*4 display mode or SEG15/ K15/ INT
Make an INT output or as a segment driver. Interrupt Flag can be read (polling) through the serial interface instead.
7.3.3. Key scan input pin is shared with segment output pin.
7.3.4. The key scanning cycle time continues to cycle, and all button have experienced a complete keyboard scanning to shake more than 20ms.
7.3.5. When the INT output is low, the INT output is valid when the "ACT" bit of the mode setting command is set to "0.
7.3.6. When the INT output is high, when the "ACT" bit of the mode setting command is set to "1", The INT output is valid at the high level.
7.4.2. When the first key is pressed, the INT function is changed and the INT FLAG bit is set to "1".
7.4.3. The "ACT" bit mode set command is set to "1". When Button data has been read, the button data register is cleared to "0",
The INT FLAG bit is set to "0" and the INT pin becomes low.
7.4.4. The "ACT" bit mode set command is set to "0". When Button data has been read, the button data register is cleared to "0",
The INT FLAG bit is set to "0" and the INT pin becomes high.
7.4.5. INT FLAG register is as follows. To clear the INT FLAG status, the button data register 0x20H ~ 0x22H must be in one
Read in operations.
CXLC89109 integrates a scanning circuit that can detect button. It has 20 inputs (K0 to K19, and SEG0 to SEG19)
In the display mode of 20*4 or 16 inputs (K0 to K15, sharing SEG15 with SEG0) in the display mode of 16*8. Key matrix
It has 20*4 display mode in 20*1 matrix or 16*8 Display mode in 16*1 matrix. The circuit connection is shown in the following figure:
8. Button data registers and commands
The address should be read continuously and completed in one operation. Button the address of the data register corresponds to the output of button data, Button data
Each byte in the register corresponds to the button data output. The mapping shown below is output from RAM data:
Button data registers are read-only. Button data register format is as follows:
8.2.2. The default value of the key scanning cycle is that the two clock cycle times are in the 20*4 display mode, and the one clock cycle time is in the 16*8 display mode.
8.2.3. Usually when Button data can be read correctly, users do not need to use this command.
8.2.4. Due to the characteristics of various liquid crystals, there will be different RC time constants during the key scanning period. If the equivalent capacitance of LCD is large,
Use this command to adjust the key scan cycle. If the scanning period of button is too long, it may affect the visual quality of LCD.
The chip is made up of I2C Protocol 2-wire serial interface for data transmission
When entering commands or displaying data, the chip must follow these steps:
(1) formation start conditions
(2) Send Slave Address
(3) command to display data transmission
(4) forming stop conditions
An ACK signal is required for data transmission. The transmitted data is composed of 8 bits. ACK is returned after 8 bits of data are transmitted.
The signal. After 8bit Data (Slave Address,Register Address,Data) is transmitted, the number of SDA at the eighth clock failling edge of the SCL
According to the output "L" signal, the output stops when the 9th SCL clock drops. When the ACK signal is not required, the eighth signal from the SCL signal
Please enter "L" until the number drops to the 9th signal ".
The slave address byte and the following startup conditions form the first byte of the master device. The upper seven bits of the first byte indicate the slave address.
The eighth bit defines whether read or write operations are set. When the R/ W bit is "1", the read operation is selected, and the write operation is selected for "0.
CXLC89109 address bit format is as follows. When an Address byte is sent, the device matches seven bits after the first start condition. If it
The device outputs a response on the SDA line.
9. Read and write operations
Data and STOP conditions. Each byte is transmitted, the chip replies through ACK.
The memory address (An) is written to the address pointer. The R / W bit (= "1") is written to the next start condition and the slave address again. In
The data in the Register starts to be transferred. The address pointer is incremented only after receiving a response clock. If the register address (An) is 0X00H ~
0X0FH, after reaching the storage location 0X0FH, The Pointer will be reset to 0X00H; If the register address (An) is 0X20H ~ 0X22H,
After the storage location is 0X22H, the pointer is reset to 0X20H.
(2.) read of consecutive addresses continues until the host sends a STOP condition.
Ten, Conclusion
CXLC89109 has become the preferred driver chip for small and medium-scale LCD applications due to its high integration, low power consumption, flexible display and key scanning configurations. Its simple I² C interface and rich support of Chinese materials greatly reduce the development threshold. For more technical details, samples or purchasing support, please visitJTM-IC official website (jtm-ic.com), we provide you with original authentic products, technical guidance and one-stop supply services.
11. Relevant chip selection guideMore similar products.....
| Model | Number of interfaces | Drive dot matrix number | Segment/bit | Co-negative Drive | Co-positive drive | Button | Encapsulation form | Remarks |
| CXLE88134N | 3 | 28 | 7*4 | 7-segment 4-bit | - | - | SOP16/DIP16 | LED panel display driver chip |
| CXLE88135N | 3 | 21 | 8*2/7*3 | 8-segment 2-bit/7-segment 3-bit | - | 6*1 | SOP16 | LED panel display driver chip |
| CXLE88136N | 3 | 35 | 5*7/8*4 | 7-segment 5-bit/8-segment 4-bit | 7 segments and 5 digits | 5*1 | SOP18/DIP18 | LED panel display driver chip |
| CXLE88137BN | 3 | 48 | 6*7/9*4 | 7-segment 6-bit/9-segment 4-bit | 7-segment 6-bit | 6*1 | SOP20 | LED panel display driver chip |
| CXLE88137N | 3 | 48 | 8*6/10*4 | 8-segment 6-bit/10-segment 4-bit | - | - | SOP20 | LED panel display driver chip |
| CXLE88138C | 4 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | 10*3 | SOP32 | LED panel display driver chip |
| CXLE88138N | 4 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | 10*3 | SOP32 | LED panel display driver chip |
| CXLE88139N | 3 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | - | SOP24/QSOP24 | LED panel display driver chip |
| CXLE88141N | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP28 | LED panel display driver chip |
| CXLE88142A | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP28 | LED panel display driver chip |
| CXLE88142E | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP28 | LED panel display driver chip |
| CXLE88143AN | 3 | 128 | 16*8 | 16-segment 8-bit | 8-segment 16-bit | - | SOP32 | LED panel display driver chip |
| CXLE88143BN | 3 | 112 | 14*8 | 14-segment 8-bit | 8-segment 14-bit | 8*2 | SOP32 | LED panel display driver chip |
| CXLE88143CN | 3 | 120 | 15*8 | 15-segment 8-bit | 8-segment 15-bit | 8*1 | SOP32 | LED panel display driver chip |
| CXLE88143DN | 3 | 96 | 12*8 | 12-segment 8-bit | 8-segment 12-bit | 8*4 | SOP32 | LED panel display driver chip |
| CXLE88143N | 4 | 128 | 16*8 | 16-segment 8-bit | 8-segment 16-bit | 8*4 | QFP44 | LED panel display driver chip |
| CXLE88147N | 3 | 80 | 10*8 | 10-segment 8-bit | 8-segment 10-bit | 8*3 | SOP28 | LED panel display driver chip |
| CXLE88148N | 3 | 64 | 8*8 | 8-segment 8-bit | 8 segments and 6 digits | 4*2 | SOP24/QSOP24 | LED panel display driver chip |
| CXLE88149B | 2 | 128 | 8*16 | 8-segment 16-bit | 16-segment 8-bit | - | SOP28, SSOP28 | LED panel display driver chip |
| CXLE88155N | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP24/SSOP24/SDIP24 | LED panel display driver chip |
| CXLE88171 | 4 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | 10*3 | SOP32 | LED panel display driver chip |
| CXLE88172 | 2 | 128 | 8*16 | 8-segment 16-bit | 16-segment 8-bit | - | SOP24 | LED panel display driver chip |
| CXLE88173 | 2 | 144 | 8*9*2 | Positive and negative push digital tube | Positive and negative push digital tube | - | QSOP24 | LED panel display driver chip |
| CXLE88174 | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | Touch Button 8 | SOP32 | LED panel display driver chip |
| CXLE88175 | 5 | 120 | 15*8 | 15-segment 8-bit | 8-segment 15-bit | 8*1/8 | QFN48 | LED panel display driver chip |
| CXLE88176 | 3 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | 10*1 | SOP24 | LED panel display driver chip |
| CXLE88156 | 3 | 128 | 8*16 | 8-segment 16-bit | 16-segment 8-bit | - | SOP32 | LED panel display driver chip |
| CXLE88134 | 3 | 28 | 7*4 | 7-segment 4-bit | - | - | SOP16/DIP16 | LED panel display driver chip |
| CXLE88135 | 3 | 21 | 8*2/7*3 | 8-segment 2-bit/7-segment 3-bit | - | 6*1 | SOP16 | LED panel display driver chip |
| CXLE88136 | 3 | 35 | 5*7/8*4 | 7-segment 5-bit/8-segment 4-bit | 7 segments and 5 digits | 5*1 | SOP18/DIP18 | LED panel display driver chip |
| CXLE88137 | 3 | 48 | 8*6/10*4 | 8-segment 6-bit/10-segment 4-bit | - | - | SOP20 | LED panel display driver chip |
| CXLE88137A | 3 | 48 | 6*7/9*4 | 7-segment 6-bit/9-segment 4-bit | 7-segment 6-bit | 6*1 | SOP20 | LED panel display driver chip |
| CXLE88138 | 4 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | 10*3 | SOP32 | LED panel display driver chip |
| CXLE88139 | 3 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | - | SOP24/QSOP24 | LED panel display driver chip |
| CXLE88140A | 4 | 77 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*1 | SOP32 | LED panel display driver chip |
| CXLE88140B | 3 | 77 | 11*7/14*4 | 11 Segment 7 bit/14 Segment 4 bit | 7-segment 11-bit | 10*3 | QFP44 | LED panel display driver chip |
| CXLE88141 | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP28 | LED panel display driver chip |
| CXLE88142 | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP28 | LED panel display driver chip |
| CXLE88143 | 4 | 128 | 16*8 | 16-segment 8-bit | 8-segment 16-bit | 8*4 | QFP44 | LED panel display driver chip |
| CXLE88143A | 3 | 128 | 16*8 | 16-segment 8-bit | 8-segment 16-bit | - | SOP32 | LED panel display driver chip |
| CXLE88143B | 3 | 112 | 14*8 | 14-segment 8-bit | 8-segment 14-bit | 8*2 | SOP32 | LED panel display driver chip |
| CXLE88143C | 3 | 120 | 15*8 | 15-segment 8-bit | 8-segment 15-bit | 8*1 | SOP32 | LED panel display driver chip |
| CXLE88143D | 3 | 96 | 12*8 | 12-segment 8-bit | 8-segment 12-bit | 8*4 | SOP32 | LED panel display driver chip |
| CXLE88144 | 3 | 35 | 7*5/8*4 | 7-segment 5-bit/8-segment 4-bit | - | 7*1 | DIP18 | LED panel display driver chip |
| CXLE88145 | 2 | 32 | 8*4 | - | 8-segment 4-bit | 8*2 | DIP18 | LED panel display driver chip |
| CXLE88146 | 2 | 48 | 8*6 | - | 8 segments and 6 digits | 8*2 | SOP20/DIP20 | LED panel display driver chip |
| CXLE88147 | 3 | 80 | 10*8 | 10-segment 8-bit | 8-segment 10-bit | 8*3 | SOP28 | LED panel display driver chip |
| CXLE88148 | 3 | 64 | 8*8 | 8-segment 8-bit | 8 segments and 6 digits | 4*2 | SOP24/QSOP24 | LED panel display driver chip |
| CXLE88149 | 2 | 128 | 8*16 | 8-segment 16-bit | 16-segment 8-bit | - | SOP28/SSOP28 | LED panel display driver chip |
| CXLE88150 | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP28 | LED panel display driver chip |
| CXLE88151 | 2 | 32 | 8*4 | 8-segment 4-bit/7-segment 4-bit | - | 7*4 | SOP16/DIP16 | LED panel display driver chip |
| CXLE88152 | 2 | 28 | 7*4 | - | 7-segment 4-bit | 7*1 | SOP16/DIP16 | LED panel display driver chip |
| CXLE88153 | 1 | 40 | 7*6/8*5 | 7-segment 6-bit/8-Segment 5-bit | 6-segment 7-bit/5-segment 8-bit | - | SOP16 | LED panel display driver chip |
| CXLE88154 | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP28 | LED panel display driver chip |
| CXLE88155 | 3 | 70 | 10*7/13*4 | 10-segment 7-bit/13-segment 4-bit | 7-segment 10-bit | 10*2 | SOP24/SSOP24/SDIP24 | LED panel display driver chip |
| CXLE88133 | 2 | 256 | 32*8/24*16 | 32-segment 8-bit/24-segment 16-bit | 8-segment 32-bit/16-segment 24-bit | - | LQFP48/LQFP52 | LED panel display driver chip |
| CXLE88132 | 4 | 256 | 32*8/24*16 | 32-segment 8-bit/24-segment 16-bit | 8-segment 32-bit/16-segment 24-bit | - | LQFP48/LQFP52 | LED panel display drive core |
