72 MHz Cortex-M3 with USB — entry-level workhorse for serial-bridge and sensor-hub designs
On-chip peripherals include brown-out detect, POR, and a watchdog timer — enough supervision to run unattended in an industrial cabinet without an external supervisor IC. The internal oscillator saves a crystal for UART or I2C operation, though a precision clock improves USB jitter margins if the layout allows.
16 KB Flash — firmware budget matters
16 KB of program Flash and 4 KB of SRAM place this part at the low end of the LPC13xx memory map. That is enough for a USB CDC virtual COM port with a command parser, or a Modbus RTU slave with a few analog inputs, but tight for a full TCP/IP stack or a graphical UI. The 8-channel 10-bit ADC covers basic sensor readout without an external converter.