PSoC1 CY8C29866-24AXI — 8-bit MCU with configurable analog and digital blocks
The Cypress CY8C29866-24AXI is an 8-bit PSoC1 microcontroller from the CY8C29xxx family, built around the M8C core running at 24 MHz. It carries 32 KB of Flash program memory and 2K x 8 of SRAM, with 64 general-purpose I/O lines brought out to a 100-pin LQFP package (100-TQFP, 14x14 mm). The part integrates a 12-channel 14-bit ADC and a 4-channel 9-bit DAC, plus a set of programmable digital and analog blocks that let you configure peripherals like counters, timers, PWMs, and filters without external glue logic. Serial connectivity covers I²C, SPI, and UART/USART, and the internal oscillator eliminates the need for an external crystal in many applications. The operating temperature range spans -40°C to 85°C, making it suitable for industrial control, sensor interfaces, and human-machine interface panels that see factory-floor or outdoor telecom environments.
What the ratings mean for your BOM
The 24 MHz core speed is the ceiling for instruction throughput — enough for control loops in the tens of kilohertz range and moderate data logging, but not for high-rate DSP. The 32 KB Flash is the firmware budget; if your application requires over-the-air updates or a large protocol stack, you will need to compress or move to a higher-density sibling. The 2K x 8 SRAM is tight — watch your stack and global variable usage, especially if you are using the USB or multiple serial buffers. The 14-bit ADC gives you 14-bit resolution across 12 multiplexed channels, which is adequate for most sensor-conditioning tasks; the 9-bit DAC is useful for generating analog setpoints or driving simple analog outputs. The 64 I/O pins in a 100-LQFP mean you have plenty of headroom for parallel displays, keypad matrices, and external memory interfaces, but the package footprint is larger than a 64-pin QFP — plan your board area accordingly.