C8051F221

Overview

The C8051F221 is a mixed-signal System-on-Chip microcontroller featuring an 8051-compatible core with up to 25 MHz clock frequency and 25 MIPS throughput. It integrates 8 kB of in-system programmable Flash memory, 256 bytes of internal data RAM, and 32 general-purpose I/O pins. The device includes an 8-bit SAR ADC with up to 100 ksps conversion rate, two comparators, hardware UART and SPI interfaces, three 16-bit timers, and a dedicated watchdog timer. Operating voltage ranges from 2.7 V to 3.6 V, with a functional temperature range of -40 °C to +85 °C.

Feature Summary

• Integrated on-chip JTAG debug circuitry enables full-speed, non-intrusive in-system debugging without external emulators.
• Hardware-implemented UART and SPI serial interfaces provide reliable communication without software bit-banging overhead.
• All Port I/O pins are 5 V tolerant, allowing direct interfacing with 5 V logic devices.

Applications

• Industrial control systems requiring mixed-signal processing
• Portable battery-powered instrumentation
• Sensor interface modules

Procurement Notes

Verify the specific package variant (LQFP-32) against the design footprint. Confirm that the 8-bit ADC resolution meets application requirements, as other family members offer 12-bit options. Ensure the development environment supports the CIP-51 core architecture for programming and debugging.

Selection Notes

Select this component when a fully integrated mixed-signal MCU with hardware serial peripherals is required. It is suitable for applications needing moderate Flash capacity and analog input capabilities within a compact LQFP-32 package. Consider alternative models if higher ADC resolution or larger memory sizes are necessary.

Part Context

The C8051F221 belongs to the C8051F2xx family of high-speed, mixed-signal MCUs manufactured by Silicon Labs. This family shares a common CIP-51 core architecture and peripheral set, differing primarily in memory size, ADC resolution, and pin count configurations across various package options.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Verify compatibility with existing firmware and hardware designs before considering any alternative components.

FAQ

Does the C8051F221 include an external crystal requirement?

No, the device features an internal programmable oscillator that can serve as the system clock, though it also supports external crystals or RC circuits.

What is the maximum ADC sampling rate for this model?

The integrated 8-bit SAR ADC supports a maximum sampling rate of up to 100 ksps.