The MC14518B dual BCD counter and the MC14520B dual binary counter are constructed with MOS P–channel and N–channel enhancement mode devices in a single monolithic structure. Each consists of two identical, independent, internally synchronous 4–stage counters.
   
• Diode Protection on All Inputs
• Supply Voltage Range = 3.0 Vdc to 18 Vdc
• Internally Synchronous for High Internal and External Speeds
• Logic Edge–Clocked Design — Incremented on Positive Transition
    of Clock or Negative Transition on Enable
• Capable of Driving Two Low–power TTL Loads or One Low–power
    Schottky TTL Load Over the Rated Temperature Range