8051 core at 67 MHz with programmable analog
The CY8C3866AXI-040 runs an 8051 core at 67 MHz — the throughput ceiling for deterministic control loops and legacy 8051 toolchains. The 64 KB flash and 8 KB RAM partition leaves headroom for a CapSense library, a USB stack, and a CANopen node in a single part. The 16-channel 20-bit delta-sigma ADC array is the standout analog peripheral: it resolves sensor signals that would otherwise need an external ADC and a separate reference. The four 8-bit DACs handle analog set-point generation or waveform output without an external converter.
Peripheral set for mixed-signal control
CapSense capacitive touch sensing, CANbus, USB, I²C, SPI, and UART/USART are all on-chip — the part replaces a discrete MCU plus a separate touch controller and a CAN transceiver in a single 100-pin package. The 62 I/O lines map to the 100-LQFP (14x14 mm) footprint. The DMA engine moves data between peripherals and memory without CPU intervention, critical for USB isochronous transfers or high-rate ADC captures.
Supply and temperature envelope
The industrial temperature grade (-40°C to 85°C) qualifies the part for factory-floor PLCs, outdoor sensor nodes, and under-hood automotive auxiliary modules.