CD4059 Program Divide-by-N Counter

Description

The CD4059 is a programmable divide-by-N down-counter that divides an input frequency by any value from 3 to 15,999. It produces a single-clock-wide output pulse at a frequency equal to input/N and supports TTL-compatible output.

The counter is preset using 16 jam inputs (J1–J16) and configured via mode-select inputs (Ka, Kb, Kc), which determine the division factor and counter structure. It consists of:

• A first (fast) counting section

• An intermediate section of three cascaded BCD decades

• An optional last counting section

Mode selection enables common frequency steps such as 10, 12.5, 20, 25, and 50, making it suitable for frequency synthesizers.

The device supports a Master Preset mode (Kb = 0, Kc = 0) to load initial values, requiring at least 3 clock cycles. After preset, counting starts with a slight delay (one extra count). A Latch Enable input can hold the output high until released.

Features

• Synchronous Programmable  N Counter: N = 3 to 9999 or 15,999

• Presettable down-counter

• Fully static operation

• Mode-select control of initial decade counting function ( 10,8,5,4,2)

• T2L drive capability

• Master preset initialization

• Latchable  N output

• Quiescent current specified to 15 volts

• Max. input leakage current of 1 µA at 15 volts, full package-temperature range

• 1 volt noise margin, full package-temperature range

• 5-V and 10-V parametric ratings

Applications

• PLL frequency synthesizers (VHF, UHF, AM, FM)

• Divide-by-R counters

• General-purpose counting (timers, totalizers, production counters)

• Fixed or programmable frequency division

• "Time out" timer for consumer-application industrial controls