The Maxim Integrated DS80C323-QCD+ is an 8-bit microcontroller built around the 8051 core, clocked at 18 MHz. It is a ROMless device — no on-chip program memory — so code resides in an external EPROM, Flash, or OTP memory accessed through the external bus interface. The part integrates 256 x 8 bytes of internal RAM, 32 I/O lines, a power-fail reset, and a watchdog timer. Packaged in a 44-lead PLCC with J-leads (44-PLCC, 16.59 x 16.59 mm body), it is intended for surface-mount assembly.
ROMless architecture — BOM implications
Because the DS80C323-QCD+ has no program memory on-chip, every design must budget for an external EPROM, Flash, or OTP memory. That adds a second IC, extra board area, and a separate programming step during manufacturing. The trade-off is flexibility: the external memory can be swapped for a different density or supplier without changing the MCU, and firmware updates can be handled by replacing the memory device — or, if using Flash, by in-system programming through the UART or SIO.
Maxim Integrated (now part of Analog Devices) is the sole manufacturer for this part. There is no second-source listed in the available records, so the BOM carries single-source exposure on the MCU itself. The part is RoHS3 compliant.