Product details

Function Counter Bits (#) 4 Technology family ACT Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Input type TTL-Compatible CMOS Output type Push-Pull Features Balanced outputs, Very high speed (tpd 5-10ns) Operating temperature range (°C) -55 to 125 Rating Catalog
Function Counter Bits (#) 4 Technology family ACT Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Input type TTL-Compatible CMOS Output type Push-Pull Features Balanced outputs, Very high speed (tpd 5-10ns) Operating temperature range (°C) -55 to 125 Rating Catalog
PDIP (N) 16 181.42 mm² 19.3 x 9.4 SOIC (D) 16 59.4 mm² 9.9 x 6
  • Inputs Are TTL-Voltage Compatible
  • Internal Look-Ahead for Fast Counting
  • Carry Output for n-Bit Cascading
  • Synchronous Counting
  • Synchronously Programmable
  • SCR-Latchup-Resistant CMOS Process and Circuit Design
  • Exceeds 2-kV ESD Protection per MIL-STD-883, Method 3015

  • Inputs Are TTL-Voltage Compatible
  • Internal Look-Ahead for Fast Counting
  • Carry Output for n-Bit Cascading
  • Synchronous Counting
  • Synchronously Programmable
  • SCR-Latchup-Resistant CMOS Process and Circuit Design
  • Exceeds 2-kV ESD Protection per MIL-STD-883, Method 3015

The ’ACT161 devices are 4-bit binary counters. These synchronous, presettable counters feature an internal carry look-ahead for application in high-speed counting designs. Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change coincident with each other when so instructed by the count-enable (ENP, ENT) inputs and internal gating. This mode of operation eliminates the output counting spikes that normally are associated with synchronous (ripple-clock) counters. A buffered clock (CLK) input triggers the four flip-flops on the rising (positive-going) edge of the clock waveform.

These devices are fully programmable; that is, they can be preset to any number between 0 and 9 or 15. Presetting is synchronous; therefore, setting up a low level at the load input disables the counter and causes the outputs to agree with the setup data after the next clock pulse, regardless of the levels of the enable inputs.

The clear function is asynchronous. A low level at the clear (CLR)\ input sets all four of the flip-flop outputs low, regardless of the levels of the CLK, load (LOAD)\, or enable inputs.

The carry look-ahead circuitry provides for cascading counters for n-bit synchronous applications without additional gating. Instrumental in accomplishing this function are ENP, ENT, and a ripple-carry output (RCO). Both ENP and ENT must be high to count, and ENT is fed forward to enable RCO. Enabling RCO produces a high-level pulse while the count is maximum (9 or 15 with QA high). This high-level overflow ripple-carry pulse can be used to enable successive cascaded stages. Transitions at ENP or ENT are allowed, regardless of the level of CLK.

The counters feature a fully independent clock circuit. Changes at control inputs (ENP, ENT, or LOAD\) that modify the operating mode have no effect on the contents of the counter until clocking occurs. The function of the counter (whether enabled, disabled, loading, or counting) is dictated solely by the conditions meeting the stable setup and hold times.

The ’ACT161 devices are 4-bit binary counters. These synchronous, presettable counters feature an internal carry look-ahead for application in high-speed counting designs. Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change coincident with each other when so instructed by the count-enable (ENP, ENT) inputs and internal gating. This mode of operation eliminates the output counting spikes that normally are associated with synchronous (ripple-clock) counters. A buffered clock (CLK) input triggers the four flip-flops on the rising (positive-going) edge of the clock waveform.

These devices are fully programmable; that is, they can be preset to any number between 0 and 9 or 15. Presetting is synchronous; therefore, setting up a low level at the load input disables the counter and causes the outputs to agree with the setup data after the next clock pulse, regardless of the levels of the enable inputs.

The clear function is asynchronous. A low level at the clear (CLR)\ input sets all four of the flip-flop outputs low, regardless of the levels of the CLK, load (LOAD)\, or enable inputs.

The carry look-ahead circuitry provides for cascading counters for n-bit synchronous applications without additional gating. Instrumental in accomplishing this function are ENP, ENT, and a ripple-carry output (RCO). Both ENP and ENT must be high to count, and ENT is fed forward to enable RCO. Enabling RCO produces a high-level pulse while the count is maximum (9 or 15 with QA high). This high-level overflow ripple-carry pulse can be used to enable successive cascaded stages. Transitions at ENP or ENT are allowed, regardless of the level of CLK.

The counters feature a fully independent clock circuit. Changes at control inputs (ENP, ENT, or LOAD\) that modify the operating mode have no effect on the contents of the counter until clocking occurs. The function of the counter (whether enabled, disabled, loading, or counting) is dictated solely by the conditions meeting the stable setup and hold times.

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Technical documentation

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Type Title Date
* Data sheet CD54ACT161, CD74ACT161 datasheet (Rev. B) 24 Mar 2003
Application note Implications of Slow or Floating CMOS Inputs (Rev. E) 26 Jul 2021
Selection guide Logic Guide (Rev. AB) 12 Jun 2017
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) 02 Dec 2015
User guide LOGIC Pocket Data Book (Rev. B) 16 Jan 2007
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection 08 Jul 2004
Application note Selecting the Right Level Translation Solution (Rev. A) 22 Jun 2004
Application note TI IBIS File Creation, Validation, and Distribution Processes 29 Aug 2002
Application note CMOS Power Consumption and CPD Calculation (Rev. B) 01 Jun 1997
Application note Designing With Logic (Rev. C) 01 Jun 1997
Application note Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc 01 Apr 1996

Design & development

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Evaluation board

14-24-LOGIC-EVM — Logic product generic evaluation module for 14-pin to 24-pin D, DB, DGV, DW, DYY, NS and PW packages

The 14-24-LOGIC-EVM evaluation module (EVM) is designed to support any logic device that is in a 14-pin to 24-pin D, DW, DB, NS, PW, DYY or DGV package,

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PDIP (N) 16 View options
SOIC (D) 16 View options

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