Encyclopedia Entry: 74AHCT123AD,118

Product Overview

Category

The 74AHCT123AD,118 belongs to the category of integrated circuits (ICs).

Use

This IC is commonly used in digital electronics for various applications such as timing and pulse generation.

Characteristics

• High-speed operation
• Low power consumption
• Wide operating voltage range
• Schmitt-trigger inputs for noise immunity
• Monostable multivibrator functionality

Package and Quantity

The 74AHCT123AD,118 is available in a small-outline integrated circuit (SOIC) package. It is typically sold in reels or tubes containing multiple units.

Essence

The essence of this product lies in its ability to generate precise timing signals and pulses in digital circuits.

Specifications

• Supply Voltage Range: 2 V to 5.5 V
• Input Voltage Range: 0 V to VCC
• Output Voltage Range: 0 V to VCC
• Operating Temperature Range: -40°C to +125°C
• Propagation Delay Time: 11 ns (typical)
• Trigger Pulse Width Range: 23 ns to 1000 ns

Pin Configuration

The 74AHCT123AD,118 has a dual 16-pin configuration with the following pinout:

___________ | | 1 -| CLR |- 2 -| A |- 3 -| B |- 4 -| RCext |- 5 -| RCext |- 6 -| GND |- 7 -| Q |- 8 -| Qn |- 9 -| Qn |- 10 -| Qn |- 11 -| Qn |- 12 -| Qn |- 13 -| Qn |- 14 -| Qn |- 15 -| VCC |- 16 -| VCC |- |___________|

Functional Features

The 74AHCT123AD,118 is a monostable multivibrator IC that can be triggered by an external signal. Its key functional features include:

• Clear (CLR) input for resetting the internal state
• A and B inputs for triggering the monostable operation
• RCext pins for connecting external resistors and capacitors to set the timing parameters
• Q and Qn outputs representing the stable and inverted states, respectively

Advantages and Disadvantages

Advantages

• High-speed operation allows for precise timing applications
• Low power consumption makes it suitable for battery-powered devices
• Wide operating voltage range provides flexibility in various circuit designs
• Schmitt-trigger inputs ensure noise immunity and reliable triggering

Disadvantages

• Limited trigger pulse width range may restrict certain applications requiring longer pulses
• Monostable functionality limits its use to specific timing-related tasks

Working Principles

The 74AHCT123AD,118 operates as a monostable multivibrator, which means it has one stable state and transitions to another state for a fixed duration upon receiving a trigger signal. The timing of the output pulse is determined by the external resistor-capacitor (RC) network connected to the RCext pins.

When a trigger signal is applied to the A or B input, the internal circuitry generates an output pulse whose width is determined by the values of the external RC components. After the specified time period, the output returns to its stable state until the next trigger signal is received.

Application Field Plans

The 74AHCT123AD,118 finds applications in various fields where precise timing and pulse generation are required. Some potential application areas include:

1. Digital Communication Systems: Timing synchronization, pulse shaping, and clock generation.
2. Industrial Automation: Control signal generation, timing circuits for sensors and actuators.
3. Test and Measurement Equipment: Pulse generation for testing purposes, time-delay circuits.
4. Consumer Electronics: Remote control systems, timing circuits for audio/video devices.

Alternative Models

For similar functionality and performance, alternative models to the 74AHCT123AD,118 include:

• 74HC123D,652
• CD74HC123M96
• SN74HC123DR

These alternatives can be considered based on specific requirements and availability.

In conclusion, the 74AHCT123AD,118 is a versatile integrated circuit that offers precise timing and pulse generation capabilities. Its high-speed operation, low power consumption, and wide operating voltage range make it suitable for various digital electronics applications. However, its monostable functionality and limited trigger pulse width range may restrict its use in certain scenarios.