67 MHz Cortex-M3 with programmable analog — what it means for the BOM
The CY8C5666LTI-LP005 is a Cypress PSOC 5 device built around a 32-bit ARM Cortex-M3 core clocked at 67 MHz. That core speed, combined with 64 KB of Flash and 16K x 8 of SRAM, puts it in the sweet spot for control-loop and human-interface applications that need moderate throughput without the cost and power of a higher-end Cortex-M4 or M7. The part integrates CapSense, DMA, LCD drive, POR, PWM, and a watchdog timer, plus a 2x12b ADC and 4x8b DAC — enough mixed-signal capability to handle touch sensing, analog front-end conditioning, and basic signal generation on a single chip. The supply range spans 1.71 V to 5.5 V, which lets it run directly from a 3.6 V Li-ion cell or a 5 V industrial bus without an extra regulator. The internal oscillator eliminates the external crystal for most timing needs, saving two pins and a few cents on the BOM.
Industrial temperature grade and package
Rated for -40°C to 85°C ambient, this part is qualified for factory automation, outdoor telecom cabinets, and under-hood automotive auxiliary modules that don't require AEC-Q100 certification. The 68-VFQFN with exposed pad (68-QFN 8x8 mm) provides a compact footprint with a thermal pad for heat sinking — useful when the on-chip peripherals are running near full duty. The ROHS3 compliance simplifies EU and global regulatory acceptance.
USB connectivity and mixed-signal peripherals
USB connectivity is on board via the UART/USART and USB interface listed in the connectivity set. That makes it straightforward to add a USB port for data logging, firmware updates, or a human-interface device without an external USB bridge chip. The CapSense block handles capacitive touch sensing for panels, sliders, and proximity detection, while the 2x12b ADC and 4x8b DAC cover analog input sampling and simple analog output generation — enough for a temperature sensor interface, a small signal generator, or a closed-loop control output.
Lifecycle and sourcing reality
The part is ROHS3 compliant, so it meets the latest EU RoHS directive without exemptions.