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LCD Driver

LCD Driver

Integrated Benefits

  • Unique combination of the most prevalent functions in small LCD equipped devices
    • LCD driver for multiplexed 4-com x 7(8)-segment displays
    • Watchdog
    • 8-byte RAM
    • Long-butom-press reset/ship-mode control
    • Flexible character generation in BLE SW
  • Unmatched small PCB footprint
  • I2C interface

Flexibility

  • Flexible character generation in system MCU
  • Easy customization of watchdog timer and reset function
  • GreenPAK GPIO routing is flexible
    ensuring the least complexity in PCB routing

Configurable GPIO

  • GreenPAK signal routing is flexible – PCB layout and routing
  • GreenPAK I/O are configurable – Pull-up/down resistors, Push-Pull, Open drain, etc.
  • GreenPAK logic is configurable – Active-low/high

LCD Drive

LCD’s common and segment signals are synchronized in time by the internal oscillator. The Common signals are generated using the DFF chain and require external resistors to output three voltage levels. Segment signals are generated by cycling through the I2C configurable ASM.

LCD Drive

System Monitor Functionalities

In addition to driving the LCD, system monitor functionalities such as watchdog timer, long-button press reset, and 8-byte RAM storage are available on the same chip. According to the application, the user can configure timings for the watchdog timer and long-button press reset.

Hardware Reset and Watchdog Timer

 

Key Design Considerations:

  • LCD Voltage Range - operating voltage range varies with type of LCD
  • LCD Speed - use smaller resistors and stronger GPIO structures for generating voltage levels of common signals
  • Current Consumption - if low current is required, then a low power mode can be implemented by turning OFF the internal oscillator and ACMP when the display isn’t needed or use an external switch to power the voltage regulator
  • I2C Speed - GreenPAK I2C is 400kHz
  • I2C Address - GreenPAK I2C can have up to 16 unique addresses
  • ASM – ASM’s RAM can be configured to display various patterns

 

Resource Utilization

SLG46537V/M-GreenPAK 5 device can integrate LCD driving along with system monitoring functionalities such as a watchdog timer, a long-button press reset, and 8-byte RAM storage into the same chip.