The Intersil HCS161MS is a radiation hardened 4-input binary, synchronous counter featuring asynchronous reset and lookahead carry logic. The HCS161MS utilizes advanced CMOS/SOS technology to achieve high-speed operation. This device is a member of the radiation hardened, high-speed, CMOS/SOS logic family. The HCS161MS is supplied in a 16-lead Ceramic Flatpack (K suffix) or an SBDIP package (D suffix).