Microchip PIC16F1938-I/SO 8-Bit Microcontroller: Architecture, Features, and Application Design Guide
The Microchip PIC16F1938-I/SO is a powerful and versatile 8-bit microcontroller (MCU) from the enhanced mid-range PIC16F family. Housed in a 28-pin SOIC (Small Outline Integrated Circuit) package, this device is engineered for a wide array of embedded control applications, balancing processing capability, power efficiency, and cost-effectiveness.
Architecture Overview
At its core, the PIC16F1938 is built upon Microchip's enhanced Harvard architecture, which features a separate program and data bus, allowing for concurrent instruction fetching and data access. This significantly boosts throughput, with most instructions executing in a single clock cycle. The MCU operates at a maximum frequency of 32 MHz, delivering up to 8 MIPS (Million Instructions Per Second). It is equipped with 14 KB of self-read/write capable Flash program memory, 512 bytes of RAM, and 256 bytes of non-volatile EEPROM data memory for storing critical data.
Key Features and Peripherals
The feature set of the PIC16F1938 is a standout aspect, making it suitable for complex designs.
Core Independent Peripherals (CIPs): A significant advantage is its array of CIPs, such as Configurable Logic Cells (CLC), which allow for the creation of custom logic functions without CPU intervention, and a Complementary Waveform Generator (CWG) for advanced motor control and power conversion.
Advanced Analog Capabilities: It integrates a sophisticated analog suite, including a 10-bit Analog-to-Digital Converter (ADC) with up to 14 channels and an internal voltage reference, two comparators, and a fixed voltage reference (FVR).
Enhanced Communication Interfaces: For connectivity, it offers multiple serial communication modules: EUSART (for UART, LIN), MSSP (for I²C and SPI), and an AUSART for asynchronous communications.
Robust Timing and Control: The controller includes multiple timers (8-bit and 16-bit), Capture/Compare/PWM (CCP) modules, and an Enhanced Capture/Compare/PWM (ECCP) module for precise pulse generation and measurement.
Low-Power Management: It features nanoWatt XLP technology, enabling extremely low power consumption in Sleep mode, which is crucial for battery-powered applications.
Application Design Guide
Designing with the PIC16F1938 involves leveraging its integrated peripherals to minimize external components and reduce system cost and complexity.
1. Motor Control: Utilize the ECCP and CWG modules to generate complementary PWM signals for efficiently driving brushed DC, stepper, or brushless DC (BLDC) motors in applications like drones, fans, and industrial automation.
2. Sensor Interface and Data Logging: The high-resolution ADC and ample EEPROM make it ideal for sensor data acquisition systems. Measure parameters like temperature, pressure, or light intensity, process the data, and store it in the non-volatile EEPROM for later retrieval.
3. Human-Machine Interface (HMI): With its 25 I/O pins, many of which are multiplexed with analog functions, the MCU can directly interface with buttons, LEDs, and segmented LCDs. The integrated capacitive sensing module (mTouch) can even be used to implement touch buttons, sliders, and proximity sensing.
4. Communication Gateway: Employ the MSSP (I²C/SPI) and EUSART modules to act as a communications bridge between sensors and a central processor or a host computer, transmitting data reliably in noisy environments.
5. Low-Power Design: For portable devices, leverage the XLP technology, multiple oscillator options (including a low-power internal oscillator), and the ability to wake from Sleep on external interrupt to maximize battery life.
The Microchip PIC16F1938-I/SO stands out as a highly integrated and flexible 8-bit microcontroller solution. Its rich set of Core Independent Peripherals (CIPs) empowers designers to create sophisticated, responsive, and power-efficient systems with reduced software overhead. From motor control and sensing to user interface and connectivity tasks, this MCU provides a compelling blend of performance and value for a vast range of embedded designs.
Keywords: PIC16F1938, Core Independent Peripherals (CIP), nanoWatt XLP Technology, Enhanced Capture/Compare/PWM (ECCP), Configurable Logic Cell (CLC).
