Counter ICs.

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Counter ICs

• CEC

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Contents

• IC 7490.
• IC 7492.
• IC 7493.
• Static Display using IC 7447 and IC 7490.

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IC 7490 Counter IC

• Monolithic counter containing four master- slave
  flip-flops.
• Additional gating to provide a divide-by-two
  counter and a three-stage binary counter for
  which count cycle length is divide-by-five.
• Gated zero reset.
• Gated set to-nine inputs for use in BCD nines
  complement applications.

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IC 7490

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IC 7490 Counter IC

• To use maximum count length (decade or four-bit
  binary), B input is connected to QA output.
• Input count pulses applied to input A.
• Symmetrical divide-by-ten count from the counters
  by connecting the QD output to A input and
  applying input count to B input, gives a
  divide-by-ten square wave at output QA.

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IC 7490
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7490

• Output QA is connected to input B for BCD count.
• Clock input to A.
• Output QD is connected to input A for bi-quinary
  count.
• Clock input to B.

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IC 7490
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IC 7492

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IC 7493

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Static DisplayIC 7447
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IC 7447

• Active low outputs to drive common anode LEDs.
• Full ripple-blanking input/output controls and a
  lamp test input.
• Automatic leading and/or trailing-edge,
  zero-blanking control (RBI and RBO).
• Lamp test (LT) performed at any time when the
  BI/RBO node is at a high logic level.

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IC 7447

• Overriding blanking input (BI) to control the
  lamp intensity (by pulsing) or to inhibit the
  outputs.
• BCD output of IC 7490 converted to seven segment
  display code using IC 7447.

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1 Hz square pulses
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Procedure
For Static Display, observe the count on the
seven segment display.
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Thank You