8-bit M8C at 24 MHz with 8 KB Flash — what this PSoC 1 brings to a control board
The Infineon (formerly Cypress) CY8C21434-24LQXI is an 8-bit PSoC 1 microcontroller from the CY8C21xxx family, built around the proprietary M8C core clocked at 24 MHz.
Flash endurance and retention — what the 8 KB means for a ten-year field life
The 8 KB of on-chip Flash is the firmware store, not a data logger. For a control application that boots from fixed code and only updates firmware a handful of times over the product's service life, the PSoC 1 Flash endurance (typically 100k program/erase cycles per sector, though not explicitly stated in this part's brief) is more than adequate. No external ECC is required for the internal Flash — the M8C core handles single-bit errors transparently. For designs that need to store calibration constants or configuration tables, the 8-bit ADC's 28-channel mux lets you digitize analog trim values and keep them in the Flash, but remember that each write cycle consumes one P/E cycle from the sector. Plan your wear-leveling strategy if the system writes to the same Flash address more than a few thousand times.
28 I/O and the 8-bit ADC — sizing the analog front end
Twenty-eight I/O pins on a 32-pin QFN leaves limited headroom for external passives, but the PSoC 1 architecture compensates by integrating configurable analog blocks. The 28-input, 8-bit ADC can scan up to 28 single-ended analog channels without an external mux — enough for a bank of thermistors, potentiometers, or current-sense resistors in a motor-drive or industrial-control panel. Each I/O can also serve as a digital input or output, PWM output, or serial-interface pin.