C8051F021 - 25MHz Mixed-Signal 8051 MCU | Silicon Labs
MPN: C8051F021 ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $52.5637 | $52.56 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
C8051F021 Overview
A microcontroller integrates a processor core, memory, digital peripherals, and analog conversion functions on one semiconductor device. The C8051F021 belongs to the 8-bit microcontroller hierarchy and provides a compact platform for controlling motors, reading sensors, driving displays, and executing real-time embedded algorithms. Its mixed-signal resources reduce the need for separate ADC and DAC components when the required conversion rates and resolution are sufficient.
The principal verified specifications include 25 MHz performance, 64 kB of Flash, 4.25 kB of RAM, 32 digital I/O pins, a 12-bit 8-channel ADC capable of 100 ksps, a 12-bit 2-channel DAC, two comparators, and five 16-bit timers. The manufacturer describes the device as an analog-intensive MCU with additional communication interfaces. Exact interface assignments, electrical limits, clock details, and programming requirements should be confirmed in the manufacturer datasheet before layout or firmware design.
C8051F021 uses the Silicon Labs C8051F02x family architecture and is identified as a mixed-signal system-on-a-chip MCU. Its combination of Flash memory, RAM, ADC, DAC, comparators, timers, and serial communications supports compact control boards where analog measurements and control outputs share the same MCU. The QFP64 package also provides a mechanically accessible footprint for conventional through-hole assembly or leaded PCB layouts.
Typical applications include industrial sensor acquisition, laboratory instrumentation, motor and actuator control, process monitoring, embedded measurement systems, and communication-enabled control nodes. The ADC can sample multiple analog inputs at up to 100 ksps, while the DAC supports two analog outputs. Firmware should configure the converter channels, establish reference and acquisition timing, and calibrate results according to the electrical characteristics in the official documentation.
For PCB design, place the MCU close to its bypass capacitors and keep analog signal routing away from high-current switching nodes. Use a stable clock and decoupling arrangement, confirm all package-specific pin functions, and provide adequate power and ground connectivity. Because the verified search results do not include complete electrical, timing, pin-function, or environmental tables, those values remain marked as data needed rather than inferred.
Drop-in alternatives for C8051F021 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with C8051F021 (same form factor and footprint) — differing in ADC Resolution, Package, DAC Resolution, Core, Product Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
C8051F020-GQ
✅ Drop-In✓ In Stock
$44.956 / Unit
View Datasheet →C8051F022
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →C8051F023
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$7.9587 / Unit
View Datasheet →C8051F022R
✅ Drop-In📋 Reference alternative (not in catalog)
C8051F021-GQ
✅ Drop-In📋 Reference alternative (not in catalog)
C8051F021 Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit mixed-signal microcontroller |
| Core | 8051-compatible CIP-51 core |
| Maximum Performance Frequency | 25 MHz |
| Flash Memory | 64 kB |
| RAM | 4.25 kB |
| Digital I/O Pins | 32 |
| ADC Resolution | 12-bit |
| ADC Channels | 8 channels |
| ADC Sampling Rate | 100 ksps |
| DAC Resolution | 12-bit |
| DAC Channels | 2 channels |
| Comparator Count | 2 |
| Timer Count | 5 × 16-bit timers |
| Package | QFP-64, 10 mm × 10 mm |
C8051F021 qfp-64, 10 mm × 10 mm Pin Configuration Guide
Pin configuration for C8051F021 (qfp-64, 10 mm × 10 mm package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for C8051F021.
Refer to the datasheet for full pin configuration.
Typical Applications
C8051F021 is suitable for 6 applications: Industrial Sensor Acquisition, Process Monitoring and Control, Laboratory Measurement Instruments, Motor and Actuator Control, Embedded Communication Control, Analog Signal Conditioning.
Industrial Sensor Acquisition
The C8051F021 fits industrial sensor-acquisition nodes because its 12-bit, 8-channel ADC can acquire signals at up to 100 ksps while 32 digital I/O pins handle sensors, alarms, and digital control lines. The 25 MHz 8051-compatible core can coordinate conversion timing, filtering, thresholds, and data packaging. Use the ADC inputs with an appropriate front end, reference, and protection network, and verify the permitted input range and accuracy in the datasheet. The 64 kB Flash supports embedded application code, while 4.25 kB of RAM supports acquisition buffers and control state.
Recommended
Process Monitoring and Control
The C8051F021 is useful for compact process-monitoring controllers because it combines an ADC, DAC, comparators, timers, and digital I/O in one 64-pin QFP device. A control loop can compare measured analog conditions against thresholds, update actuator outputs through the two-channel DAC or digital lines, and schedule sampling with five 16-bit timers. The 25 MHz performance supports responsive firmware, but loop timing and accuracy must be verified against the complete electrical specifications. The integrated resources reduce board area when the application does not require higher converter performance.
Recommended
Laboratory Measurement Instruments
C8051F021-based instruments can combine signal acquisition, calibration, display control, and data communication in a compact embedded platform. Its 8-channel 12-bit ADC is appropriate for sensors and measurement front ends operating within the specified input limits, while the two 12-bit DAC channels can generate control or reference signals. The MCU’s five timers help organize sampling intervals and instrument timing. Designers should include calibration, input protection, reference design, and analog grounding in the system architecture rather than treating the ADC as an unrestricted universal voltmeter.
Recommended
Motor and Actuator Control
The C8051F021 can serve as the supervisory controller in motor and actuator systems where local sensing, timing, and analog control are required. Digital I/O handles limit switches, enable signals, status inputs, and driver-control outputs, while the ADC monitors current, position, or temperature-derived analog signals. The five 16-bit timers support pulse, interval, and scheduling tasks, and the DAC can provide limited analog command or bias signals where appropriate. Power-stage isolation, flyback protection, driver timing, and thermal design remain external to the MCU and must be validated at the system level.
Recommended
Embedded Communication Control
The C8051F021 can serve as a compact control node in equipment that needs local logic plus analog monitoring. Silicon Labs describes additional communication interfaces, while the device provides 32 digital I/O pins for interface control and status handling. Firmware can use the communication peripheral for host or peripheral connectivity, provided the exact interface type, pin multiplexing, baud-rate range, and electrical standard are confirmed in the device documentation. The 64 kB Flash and 4.25 kB RAM make the device suitable for protocol handling and supervisory logic, but networking performance depends on the selected interface and firmware design.
Recommended
Analog Signal Conditioning
The C8051F021 is appropriate for compact analog signal-conditioning subsystems because it integrates an 8-channel 12-bit ADC, a two-channel 12-bit DAC, and two comparators. A design can acquire multiple sensor inputs, compare thresholds locally, apply calibration, and generate control or test signals without adding separate converters. The ADC’s 100 ksps stated rate supports many low- and moderate-bandwidth measurement tasks, but bandwidth, noise, settling time, reference accuracy, and input-range limits must be obtained from the official datasheet. Analog layout should prioritize short traces, controlled grounding, and separation from switching nodes.
Recommended
Engineering reference data for C8051F021 — comparison, design guidance, and compliance information.
Selection Guide
Key Differentiators
- Integrated mixed-signal conversion resources (vs Generic 8-bit microcontroller alternatives)
- Performance and memory balance (vs C8051F020)
- Analog and digital integration for control systems (vs C8051F022)
- Orderable package identification (vs C8051F021-GQ)
Design Notes
Place the MCU and its required bypass capacitors close together, following the manufacturer’s recommended power and ground layout. Route analog ADC and DAC signals away from high-current switching paths, clock edges, and digital outputs where possible. The verified data confirms QFP64 and 10 mm × 10 mm dimensions, but it does not provide exact pin names, exposed-pad details, or recommended capacitor values; use the official package drawing and schematic guidance before release to manufacturing.
Validate the supply range, decoupling, startup behavior, and analog reference arrangement against the current manufacturer datasheet. The supplied search results identify the MCU as a mixed-signal device with ADC and DAC resources, but they do not state the complete voltage ratings or recommended external component values. Do not infer those values from the 25 MHz clock or from generic 8051 designs.
Do not treat a related C8051F02x device as an automatic replacement. Confirm package dimensions, pin assignments, Flash and RAM capacity, ADC and DAC channels, communication peripherals, supply voltage, clock requirements, and programming behavior before substituting C8051F020, C8051F022, C8051F023, or another candidate. The verified evidence establishes related-family status but not complete pin-to-pin interchangeability.
For the 12-bit ADC channels, keep analog traces short, use a stable reference strategy, and provide appropriate source impedance and sampling networks. For DAC outputs and digital control signals, isolate sensitive analog paths from switching nodes and verify output loading against the electrical limits. The verified information establishes converter resolution and channel counts, while input-range, bandwidth, output-drive, and timing values remain datasheet-dependent.
Compliance Information
The supplied verified search data does not explicitly state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. AEC-Q100 is not applicable as an automotive qualification classification unless the exact device is separately qualified, which the supplied data does not establish.
