80C51 core at 48 MHz with USB — what this 8-bit MCU brings to the BOM
The Microchip AT89C5130A-S3SUM is an 8-bit MCU built around the 80C51 core, clocked at 48 MHz. It carries 16 KB of on-chip Flash program memory, 1.25 KB of RAM, and a separate 4 KB EEPROM block.
34 general-purpose I/O lines are available, along with I²C, SPI, and two UART/USART serial interfaces. On-chip peripherals include a PWM generator, a watchdog timer, and a power-on reset circuit.
52-PLCC footprint — board layout and rework notes
The part comes in a 52-lead PLCC (J-lead) package, supplier device code 52-PLCC (19.15x19.15 mm). The J-lead form factor is a legacy SMT package that still sees use in high-reliability and retrofit designs because the leads are more robust than fine-pitch QFP. The 0.050-inch pitch requires a standard PLCC-52 footprint; a two-layer board can route all signals if the decoupling caps are placed close to the Vcc/Vss pairs. Rework with a hot-air station is straightforward — the J-leads are visible and accessible for touch-up.
The part is ROHS3 compliant.