This application note describes how to drive liquid crystal displays (LCDs) with STM32F10xxx microcontrollers (MCUs), that is without any specific on-chip LCD driver hardware
This document details a method for driving liquid crystal displays (LCD) using STM32F10xxx microcontrollers without relying on dedicated on-chip LCD driver hardware. It explains the principles of LCD operation and provides techniques for generating the necessary drive signals, including single, duplex, and quadruplex modes. The note covers firmware implementation details, such as using standard I/O ports and timers to control the display, and includes a description of the STM32F10xxx LCD glass library.
The guide also addresses low-power management strategies for battery-powered applications, offering measurements on current consumption and CPU load. It provides hardware implementation examples, including schematic diagrams and connection details for specific LCD models, ensuring users can integrate the solution with minimal external components.
| CPU Load | around 0.05% (at 72 MHz) |
|---|---|
| External Components | two external resistors per COM line |
| DC Value Limit | never more than 100 mV |
| Frequency Range | 30 Hz to 200 Hz typically |
Yes, the technique described allows driving LCDs without any specific on-chip LCD driver hardware.
The solution keeps the number of external components to a minimum, requiring two external resistors per COM line.
The applied DC value should never exceed 100 mV to prevent shortening the LCD lifetime.