C8051F931-GMR

Overview

The C8051F931-GMR is an 8-bit microcontroller from the Silicon Labs C8051F9xx series, featuring a high-speed 8051 core with up to 25 MIPS throughput at a 25 MHz clock. It includes 64 kB of in-system programmable Flash memory and 4352 bytes of internal data RAM. The device supports a supply voltage range of 0.9 V to 3.6 V, utilizing a built-in DC-DC converter for one-cell mode operation. Key peripherals include a 10-bit SAR ADC with 23 external inputs, two comparators, hardware SMBus, dual SPI, and UART interfaces. It operates within a temperature range of -40°C to +85°C and is housed in a 32-pin QFN package.

Feature Summary

• Integrated SmaRTClock real-time clock oscillator supporting low-power timekeeping
• Built-in DC-DC converter enabling efficient single-cell battery operation
• On-chip debug circuitry facilitating non-intrusive in-system programming and debugging
• Hardware support for capacitive touch sense inputs via analog multiplexers

Applications

• Single or dual battery powered portable devices
• Low power sensor nodes requiring precise timing
• Battery management systems with voltage monitoring
• Industrial control applications with I/O isolation requirements

Procurement Notes

Verify the specific suffix GMR indicates tape and reel packaging when sourcing components. Confirm that the ordering part number matches the exact memory configuration required, as the F93x family shares pinouts with variants having different Flash sizes. Ensure compatibility with development tools such as the ToolStick adapter for initial prototyping and firmware validation.

Selection Notes

Select this component when a robust 8051 architecture is needed alongside extensive analog capabilities like a high-resolution ADC and multiple comparators. The integrated DC-DC converter makes it suitable for designs constrained by strict power budgets or single-cell lithium battery supplies. Consider the 32-QFN package dimensions if board space is limited compared to larger LQFP options.

Part Context

This MCU belongs to the C8051F9xx family, which emphasizes mixed-signal integration on a standard 8051 core. The F931 variant specifically provides the maximum Flash capacity within its sub-series. It is designed to replace older discrete solutions by combining processing, analog conversion, and communication interfaces into a single compact silicon die.

Replacement Considerations

C8051F930-G-GMR

FAQ

How does the device handle voltage regulation in single-cell mode?

The C8051F931 utilizes a built-in DC-DC converter to step up the input voltage, allowing stable operation even when the supply drops below the internal regulator threshold.

What clock sources are available for the SmaRTClock?

The SmaRTClock can operate using an external 32 kHz crystal or switch to an internal self-oscillate mode to minimize external component count.