C8051F821-GS

Overview

The C8051F821-GS is a mixed-signal ISP Flash microcontroller from the C8051F80x-83x family. It features a high-speed 8051 core with up to 25 MIPS throughput at a 25 MHz clock. The device includes up to 16 kB of in-system programmable Flash memory and up to 512 bytes of internal data RAM. Key analog peripherals consist of a 10-bit ADC supporting up to 500 ksps, a capacitive-to-digital converter with 16-bit resolution, and comparators. Digital interfaces include an enhanced UART, SMBus, and SPI. The unit operates on a supply voltage of 1.8 to 3.6 V and supports packages such as 16-pin SOIC, 20-pin QFN, and 24-pin QSOP within a temperature range of –40 to +85 °C.

Feature Summary

• Integrated Capacitance to Digital Converter supporting buttons, sliders, wheels, and capacitive proximity sensing with auto-scan capabilities.
• On-chip debug circuitry enabling full speed, non-intrusive in-system debug without external emulators.
• Pipelined instruction architecture executing 70% of instructions in one or two system clocks for efficient processing.
• In-system programmable Flash memory allowing field upgrades and non-volatile data storage in 512-byte sectors.

Applications

• Capacitive touch sensing interfaces
• Mixed-signal embedded control systems
• Low-power portable instrumentation

Procurement Notes

Verify component authenticity through authorized Silicon Labs distributors. Confirm package type matches design requirements. Check datasheet revision status as this family is marked Not Recommended for New Designs. Ensure environmental compliance documentation aligns with project specifications.

Selection Notes

Select based on required I/O count and peripheral availability. Compare against newer EFM8 series for long-term supply assurance. Evaluate power consumption profiles across active and sleep modes. Verify compatibility with existing development tools like Simplicity Studio.

Part Context

Part of the C8051F80x-83x mixed-signal MCU family. Shares architectural similarities with other devices in the series while differing in specific memory sizes and pin configurations. Designed for applications requiring integrated analog and digital functions in a compact footprint.

Replacement Considerations

EFM8BB31F64G-QFN32 is recommended as a replacement due to End of Life status for the C8051F80x-83x family. Verify pinout compatibility and software migration efforts when transitioning to the EFM8 Busy Bee series.

FAQ

What is the maximum sampling rate of the ADC?

The 10-bit ADC supports a maximum sampling rate of 500 ksps.

Does the device support capacitive sensing?

Yes, it includes a dedicated Capacitance to Digital Converter supporting up to 16 input channels with 16-bit resolution.