Silicon Labs C8051F394-A-GMR

Overview

C8051F394-A-GMR from Silicon Laboratories is a 50 MIPS, 16 kB Flash, 512 B EEPROM mixed-signal 8051 MCU with integrated 10-bit ADC (500 ksps), dual 10-bit current-output DACs, precision temperature sensor (±2 °C), and 21 GPIO in 24-pin QFN. It operates from 1.8–3.6 V and supports –40 to +105 °C industrial temperature range.

For engineers reviewing the C8051F394-A-GMR datasheet, C8051F394-A-GMR pinout, C8051F394-A-GMR application, or C8051F394-A-GMR equivalent, this device serves as a low-power, high-precision embedded controller for sensor interface, closed-loop analog control, and battery-powered instrumentation where on-chip ADC/DAC, temperature sensing, and crystal-less UART are critical.

Technical Context

The C8051F394-A-GMR implements a pipelined CIP-51 8051 core delivering 50 MIPS at 50 MHz, with on-the-fly clock source switching between 49 MHz ±2% internal oscillator (enabling crystal-less UART) and 80 kHz low-power oscillator. Its analog subsystem includes two independent 10-bit IDACs with programmable update triggers (timer overflow, CNVSTR edge, or on-demand), and a 10-bit ADC with 16-channel multiplexer, differential/single-ended input support, and window comparator.

Digital peripherals include UART0, two SMBus (I²C-compatible) interfaces, SPI0, six 16-bit timers, and a 16-bit programmable counter array (PCA) supporting PWM, capture/compare, and watchdog functions. Memory architecture comprises 16 kB flash (512-byte sectors), 1 kB RAM (256 + 768), and 512 B byte-programmable EEPROM rated for 1 million write/erase cycles.

Key Specifications

Pinout & Package

Package: 24-pin QFN (4 × 4 mm, 0.5 mm pitch), wettable flank, RoHS-compliant, moisture sensitivity level 3 (MSL3).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar mixed-signal microcontroller applications.

Compared with C8051F394-A-GMR, C8051F390-A-GMR reduces analog output flexibility by omitting IDA1, while MSP430F249IPN trades integrated mixed-signal features for raw memory and ultra-low-power sleep - making C8051F394-A-GMR optimal for compact, self-contained analog control where DAC+ADC+temp sensor co-location matters.

Availability

C8051F394-A-GMR is available at Aetrix Electronics and suitable for industrial sensor nodes, thermal monitoring systems, portable medical instruments, and energy-efficient analog controllers requiring stable component supply and long-term production continuity.

Supply support for C8051F394-A-GMR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Silicon Labs is a fabless semiconductor company specializing in silicon, software, and solutions for IoT, timing, and mixed-signal applications, with engineering centers across North America and Asia.

The C8051F39x family delivers highly integrated, low-power 8051-based MCUs targeting cost-sensitive, space-constrained embedded systems needing precision analog front-ends and robust debug capabilities.

FAQ

What is the maximum ADC sampling rate supported by the C8051F394-A-GMR?

The C8051F394-A-GMR supports a programmable ADC throughput of up to 500 ksps. This maximum rate assumes single-ended input configuration, internal reference, and minimal setup time; actual achievable rate depends on resolution mode, input multiplexer settling, and system clock configuration. The ADC0 block is fully documented in Section 9 of the Rev. 1.3 datasheet.

Does the C8051F394-A-GMR include an on-chip temperature sensor, and what is its accuracy?

Yes, the C8051F394-A-GMR includes an integrated precision temperature sensor accurate to ±2 °C across the full –40 to +105 °C operating range without user calibration. This specification is validated per Section 8 and Figure 7.3 of the official datasheet and applies directly to the C8051F394-A-GMR variant.

Can the C8051F394-A-GMR operate without an external crystal?

Yes, the C8051F394-A-GMR can operate without an external crystal using its 49 MHz ±2% internal precision oscillator, which supports crystal-less UART operation. This oscillator also enables fast wake-from-suspend mode with sub-1 μs stabilization, making it suitable for low-power intermittent sensing applications.

How many DAC channels does the C8051F394-A-GMR have, and what type are they?

The C8051F394-A-GMR has two independent 10-bit current-output DACs (IDA0 and IDA1). Each supports programmable update scheduling - including on-demand, timer-triggered, or edge-triggered modes - and retains output value across reset events for continuous analog output in control loops.

Is the C8051F394-A-GMR pin-compatible with other devices in the C8051F39x family?

Yes, the C8051F394-A-GMR uses the 24-pin QFN package shared with C8051F390/391/395 and all C8051F37x variants, and shares identical pinout per Figure 4.2 of the datasheet. However, functional differences exist - e.g., C8051F392/393 use 20-pin QFN and lack IDA1 - so PCB layout must match the exact 24-pin variant.