C8051F351

Overview

The C8051F351 is a mixed-signal 8-bit microcontroller featuring a high-speed 8051 core operating at up to 50 MHz. It integrates 8 kB of in-system programmable Flash memory and 768 bytes of RAM. The device includes a 24-bit sigma-delta ADC with eight input channels, two 8-bit current-output DACs, and a voltage comparator. Digital peripherals consist of four 16-bit timers, three PCA channels, an enhanced UART, SMBus, and SPI interfaces. It operates on a 2.7 V to 3.6 V supply within the -40°C to +85°C temperature range.

Feature Summary

• High analog integration with a 24-bit ADC supporting up to 1 ksps conversion rates and a programmable gain amplifier.
• On-chip debug circuitry enabling full-speed, non-intrusive in-system debugging without external emulators.
• Pipelined instruction architecture delivering up to 50 MIPS throughput with most instructions executing in one or two system clocks.
• Flexible clocking options including a precise internal oscillator and support for external crystal or RC sources.

Applications

• Portable medical equipment
• Weigh scales
• Test equipment
• Fiber optic systems

Procurement Notes

Verify the specific package variant required, as the C8051F351 is available in both 28-pin MLP and 32-pin LQFP configurations. Confirm that the selected part number aligns with the intended PCB footprint and pinout requirements. Ensure compatibility with the Silicon Labs development tools for programming and debugging. Check for any specific ordering suffixes that may indicate tape-and-reel packaging versus tube quantities if applicable to the manufacturing process.

Selection Notes

Select the C8051F351 when high-resolution analog signal acquisition is critical due to its 24-bit ADC and programmable gain capabilities. Choose this model over other C8051F35x variants specifically requiring the 24-bit ADC resolution rather than the 16-bit option found in siblings like the C8051F350. Consider this MCU for designs needing a standalone system-on-chip solution with integrated power management features such as the on-chip VDD monitor and watchdog timer.

Part Context

The C8051F351 belongs to the C8051F35x family of analog-intensive microcontrollers from Silicon Labs. This series shares a common architectural foundation but varies in peripheral configurations, primarily regarding ADC resolution and communication interfaces. The F351 is distinguished by its 24-bit ADC, whereas other members like the F350 offer different feature sets tailored for varying application complexities within the same ecosystem.

Replacement Considerations

Direct substitutes within the same family include the C8051F350, C8051F352, and C8051F353, though these differ in ADC resolution or interface availability. Verify pin compatibility and software register mapping before swapping between these variants to ensure seamless integration into existing hardware designs.

FAQ

What is the maximum sampling rate of the ADC on the C8051F351?

The 24-bit sigma-delta ADC supports programmable conversion rates up to 1 ksps.

Does the C8051F351 require an external emulator for debugging?

No, it features on-chip debug circuitry that facilitates full-speed, non-intrusive in-system debugging without the need for an external emulator.