50 MHz 8051 with integrated CapSense and USB — PSOC 3 CY8C3245PVI-150
The Infineon CY8C3245PVI-150 is an 8-bit MCU built around the 8051 core, running at 50 MHz, and part of the PSOC 3 CY8C32xx family. The standout features are the integrated CapSense touch-sensing engine, a full-speed USB 2.0 interface, and a segment LCD drive controller, all in a 48-pin SSOP package with 25 I/O. The supply range spans 1.71 V to 5.5 V, so it can run directly from a Li-ion cell or a 3.3 V / 5 V rail without an extra regulator.
Peripheral set and memory — what fits where
The 4 KB RAM is tight for heavy data buffering — plan for external SRAM over the EBI/EMI interface if you need more. The 12-bit ADC with 16 channels and the single 8-bit DAC handle sensor acquisition and analog output without an external converter.
Package and power — layout notes
The 25 I/O are 5 V tolerant on most pins, simplifying level translation to legacy peripherals. The internal POR and WDT reduce external supervisor IC count.
It is ROHS3 compliant.