MD82C59A/B

The MD82C59A/B from Renesas Electronics is a CMOS programmable interrupt controller (PIC) designed to manage prioritized interrupt requests in microprocessor-based systems. Operating as a drop-in replacement for the industry-standard 8259A, this device provides eight levels of vectored priority interrupts, expandable to 64 through master-slave cascading. The fully static CMOS design ensures low power dissipation and broad operating voltage margins, while the programmable priority modes (fully nested, rotating, and special mask) allow flexible system configuration. Housed in a ceramic dual-in-line package (CDIP), the component offers hermetic sealing for enhanced reliability in harsh environments, and the ‘M’ prefix typically denotes a military temperature range of -55°C to +125°C.

Typical applications span embedded computing platforms in defense avionics, industrial automation, and legacy aerospace systems where 80C86/88 or compatible processors remain in service. The device is also found in high-reliability communication subsystems, test equipment, and mission-critical control units that require deterministic interrupt handling. From a procurement standpoint, the MD82C59A/B is a mature product; availability in CDIP packaging may be limited to specialized high-reliability supply channels. Designers should consider lifecycle management, as CMOS interrupt controllers in hermetic packages are often subject to long lead times or end-of-life notices. Verifying the exact part suffix and manufacturer’s classification (e.g., /883 compliant processing) is essential to confirm compliance with military or aerospace-grade procurement specifications.