ST6225C

ST6225C Microcontroller Technical Summary

Overview

The ST6225C is an 8-bit microcontroller from STMicroelectronics, designed for embedded control applications. It features a robust architecture with integrated peripherals, making it suitable for a wide range of industrial, automotive, and consumer electronics applications. The microcontroller is built on a high-performance ST6 core, offering efficient processing capabilities with low power consumption.

Key Features

• 8-bit ST6 Core: Optimized for low-power operation with efficient instruction execution.
• Memory: Includes ROM for program storage and RAM for data handling.
• Clock System: Supports main oscillator and low-frequency auxiliary oscillator (LFAO) for flexible clocking options.
• Power Saving Modes: Features WAIT and STOP modes to minimize power consumption.
• Digital Watchdog: Integrated watchdog timer for system reliability.
• Interrupt Handling: Multiple interrupt sources with configurable priority levels.
• I/O Ports: Configurable bidirectional I/O pins with safe state switching.
• Timer Module: Built-in timer for event counting and PWM generation.
• A/D Converter: On-chip analog-to-digital converter for sensor interfacing.

Applications

The ST6225C is widely used in applications requiring embedded control, including:

• Home appliances (washing machines, refrigerators)
• Automotive systems (dashboard controls, sensors)
• Industrial automation (motor control, PLCs)
• Consumer electronics (remote controls, toys)
• Medical devices (portable monitoring equipment)

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage (V_DD): -0.3V to +7.0V
• Input Voltage (V_IN): -0.3V to V_DD + 0.3V
• Operating Temperature: -40°C to +85°C
• Storage Temperature: -65°C to +150°C

Recommended Operating Conditions

• Supply Voltage (V_DD): 4.5V to 5.5V
• Operating Temperature: -40°C to +85°C
• Clock Frequency: Up to 8 MHz (main oscillator)

DC Electrical Characteristics

• Input High Voltage (V_IH): 0.7 × V_DD (min)
• Input Low Voltage (V_IL): 0.3 × V_DD (max)
• Output High Voltage (V_OH): V_DD - 0.5V (min)
• Output Low Voltage (V_OL): 0.4V (max)
• Power Consumption (Active Mode): 5 mA (typical at 5V, 8 MHz)
• Power Consumption (STOP Mode): 1 µA (typical)

AC Electrical Characteristics

• Instruction Cycle Time: 1 µs (at 8 MHz)
• Reset Pulse Width: 10 µs (min)
• Interrupt Response Time: 4 clock cycles (typical)

A/D Converter Characteristics

• Resolution: 8-bit
• Conversion Time: 20 µs (typical)
• Input Voltage Range: 0V to V_DD
• Integral Nonlinearity (INL): ±1 LSB (max)

Timer Characteristics

• Timer Resolution: 8-bit
• Clock Sources: Internal or external
• PWM Mode: Supported with configurable duty cycle

Package Information

The ST6225C is available in multiple package options, including:

• DIP (Dual In-line Package): 20-pin, 28-pin options
• SOIC (Small Outline Integrated Circuit): 20-pin, 28-pin options
• TSSOP (Thin Shrink Small Outline Package): 20-pin, 28-pin options

Mechanical Dimensions

• 20-pin DIP: 26.2 mm × 6.35 mm (length × width)
• 28-pin SOIC: 17.9 mm × 7.5 mm (length × width)
• 28-pin TSSOP: 9.7 mm × 4.4 mm (length × width)

Memory Organization

Program Space

The ST6225C features a dedicated program memory space with ROM for firmware storage. The memory map includes:

• ROM Size: Up to 8 KB (model-dependent)
• Program Counter (PC): 12-bit, addressing up to 4 KB directly

Data Space

The microcontroller includes RAM for data storage and stack operations:

• RAM Size: 256 bytes (typical)
• Stack Space: 6-level hardware stack
• Data Window Register (DWR): Enables efficient data access

Programming Modes

The ST6225C supports flexible programming options:

• Option Bytes: Configurable settings for hardware behavior
• EPROM Erasing: UV-erasable versions available
• In-System Programming (ISP): Supported via serial interface

Peripheral Modules

I/O Ports

The microcontroller features configurable I/O ports with multiple operating modes:

• Bidirectional I/O: Configurable as input or output
• Open-Drain Options: Available for specific pins
• Safe Switching: Controlled state transitions to prevent glitches

Timer Module

The integrated timer supports multiple operating modes:

• Event Counting: External or internal clock sources
• PWM Generation: Configurable frequency and duty cycle
• Interrupt Capability: Timer overflow triggers interrupts

A/D Converter

The on-chip ADC enables analog signal processing:

• Multiplexed Inputs: Supports multiple analog channels
• Single-Shot/Continuous Mode: Configurable conversion modes
• Interrupt on Conversion Complete: Efficient data handling

Software Development

The ST6225C is supported