16-bit MCS-96 at 40 MHz – ROMless, 5V, commercial temp
The YW80C196NU40 is an Intel MCS-96 16-bit microcontroller running at 40 MHz. It carries 1K x 8 of on-chip RAM for register file and scratchpad, but has no internal program memory — firmware lives in an external ROM or Flash device. The part is rated for 4.5 V to 5.5 V supply and operates over the 0°C to 70°C commercial temperature range. Peripherals include PWM outputs and a serial I/O (SIO) channel, with 32 general-purpose I/O lines brought out. The oscillator is external, so a crystal or clock source is required on the board. Package is a 100-pin BFQFP for surface-mount assembly.
ROMless architecture — external program store required
Because the YW80C196NU40 is ROMless, the design must include an external EPROM, Flash, or OTP memory mapped into the MCS-96 bus. That adds board area and a separate memory device to the BOM, but also gives flexibility in code size and field-update strategy — swap the external part rather than respin the MCU. The 100-BFQFP pinout exposes the full address/data bus for external memory interface.