74193 (4-bit binary up/down counter with synchronous reset )

Description

The 74193 is a 4-bit binary up/down counter with synchronous reset and clear. It is part of the 7400 series of integrated circuits and is used in digital circuits for counting applications, typically in systems where binary counting, timing, or sequencing is needed.

74193 IC Description:

The 74193 is a 4-bit binary up/down counter, meaning it can count both up (increasing) and down (decreasing) based on a control signal. It can count from 0 to 15 (binary 0000 to 1111). The IC has asynchronous inputs for clear and load, and its counting behavior is controlled by the up/down input and the clock.

Key Features:

• 4-bit Binary Up/Down Counter: The IC can count from 0 to 15 in binary (0000 to 1111).
• Synchronous Reset: It has a reset pin (CLR) that resets the counter to 0 when activated.
• Count Control: The Up/Down (U/D) input controls whether the counter counts up or down.
• Synchronous Operation: The counter increments or decrements on the rising edge of the clock.
• Buffered Outputs: The counter’s outputs (Q0-Q3) are buffered, meaning they can drive logic-level circuits or external components directly.
• Active-low Asynchronous Clear: The clear (CLR) pin is used to reset the counter asynchronously when held low.

Pin Configuration (16-pin package):

Here’s the pinout for the 74193 4-bit binary up/down counter:

1. Q0: Output bit 0 (Least Significant Bit).
2. Q1: Output bit 1.
3. Q2: Output bit 2.
4. Q3: Output bit 3 (Most Significant Bit).
5. Clock (CLK): The clock input. The counter increments or decrements on the rising edge of the clock.
6. Up/Down (U/D): This input controls the counting direction. When HIGH (1), the counter counts up; when LOW (0), it counts down.
7. Clear (CLR): Active-low asynchronous clear input. When LOW, the counter is reset to 0.
8. Load (LOAD): Active-low load input. When LOW, the data on the Data Inputs (D0-D3) is loaded into the counter.
9. D0: Data input bit 0 (Least Significant Bit).
10. D1: Data input bit 1.
11. D2: Data input bit 2.
12. D3: Data input bit 3 (Most Significant Bit).
13. Vcc: Supply voltage (typically 5V).
14. GND: Ground connection.

How It Works:

• Counting Operation:
  • The 74193 counts in binary on the rising edge of the clock input (CLK).
  • The Up/Down (U/D) input controls the counting direction:
    • When U/D = 1 (HIGH), the counter counts up (increments).
    • When U/D = 0 (LOW), the counter counts down (decrements).
• Clear Operation:
  • The CLR input is an asynchronous active-low reset. When CLR = 0, the counter is reset to 0000 (binary 0) immediately, regardless of the clock or other inputs.
• Load Operation:
  • The LOAD input is used to load a specific value (D0 to D3) into the counter. When LOAD = 0, the counter will take the 4-bit value present on the data inputs (D0-D3) and store it as the current count.
• Clock Input:
  • The clock (CLK) input is used to increment or decrement the counter. The counter responds to the rising edge of the clock signal. Every time the clock rises, the counter either increments or decrements based on the Up/Down input.

Truth Table:

Note:

• X means the state of that input does not affect the outcome.
• U/D = 0 means the counter is in down counting mode.
• U/D = 1 means the counter is in up counting mode.

Applications:

1. Frequency Dividers: The 74193 can be used to divide a high-frequency clock signal by a factor of up to 16, depending on the counter’s current value.
2. Timers and Counters: This IC is commonly used in timing circuits where precise counting of clock pulses is needed.
3. Event Counting: It can be used in digital systems to count events, such as the number of pulses from a sensor.
4. Digital Clocks: The 74193 can be used as part of a digital clock circuit where it counts time intervals and produces clock outputs.
5. Sequence Generators: In applications that require generating specific counting sequences, this IC can be used for controlling the state of other logic circuits based on the count.

Electrical Characteristics:

• Supply Voltage (Vcc): Typically 5V (with a range of 4.5V to 5.5V).
• Current Consumption: The IC operates with low power consumption typical of CMOS devices.
• Output Drive Capability: The IC can drive standard logic-level circuits and is suitable for use in digital designs.

Example Application Circuit:

In a simple counting application, you could connect the 74193 to a clock signal, use the Up/Down input to select counting direction, and monitor the outputs (Q0-Q3) to track the count. If you need the counter to reset after reaching a specific value, you could use the Clear pin to reset it to 0000 when needed.