C8051F126

Overview

The C8051F126 is a mixed-signal System-on-Chip microcontroller featuring a high-speed CIP-51 core with 50 MIPS throughput. It integrates 128 kB of in-system programmable Flash memory and 8448 bytes of internal RAM. The device includes a 10-bit, 8-channel ADC operating up to 100 ksps, two 12-bit DACs, and two analog comparators. Digital peripherals comprise hardware SMBus, SPI, and dual UART interfaces alongside five 16-bit timers and a Programmable Counter Array. It operates within a voltage range of 3.0–3.6 V at maximum speed and supports industrial temperatures from -40°C to +85°C.

Feature Summary

• High-performance pipelined CIP-51 core executing 70% of instructions in one or two system clock cycles
• Integrated on-chip JTAG debug circuitry enabling full-speed non-intrusive in-circuit debugging
• Analog-intensive design with programmable gain amplifiers and data-dependent windowed interrupt generators
• Flexible digital I/O configuration via programmable crossbar decoder supporting multiple serial protocols

Applications

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

Procurement Notes

Verify the specific revision status as this component family has been designated End of Life (EOL). Confirm availability through Last Time Buy (LTB) channels if immediate procurement is required. Ensure that the selected package variant matches the intended PCB footprint constraints. Validate that the application environment remains within the specified industrial temperature range and voltage limits defined in the datasheet.

Selection Notes

Select this model for applications requiring high analog integration alongside robust digital communication capabilities. The inclusion of dual 12-bit DACs and an 8-bit ADC distinguishes it from variants lacking these specific converters. Consider the 100-pin TQFP package for maximum GPIO availability. Evaluate the need for the 16x16 MAC engine, which is present in other family members but absent in the F126.

Part Context

This device belongs to the C8051F12x series of highly integrated mixed-signal microcontrollers produced by Silicon Labs. It utilizes the CIP-51 architecture, offering significant performance improvements over standard 8051 cores. The series is designed for standalone system-on-chip solutions, reducing external component count by integrating oscillators, voltage monitors, and extensive peripheral sets onto a single die.

Replacement Considerations

Silicon Labs recommends the EFM8BB31F64G-QFN32 as a replacement for this part. Note that the replacement utilizes a different architecture and pinout, requiring schematic and firmware redesign.