7414 Hex Inverting Schmitt Trigger - Technical Summary

Overview

The 7414 is a hex inverting Schmitt trigger integrated circuit belonging to the 7400 series of logic devices. It contains six independent Schmitt trigger inverters, each with hysteresis for noise immunity and improved switching characteristics. The device is widely used in digital systems for signal conditioning, waveform shaping, and noise filtering applications.

As a Schmitt trigger device, the 7414 features different input threshold voltages for positive-going and negative-going signals, providing hysteresis that prevents output oscillations when slowly changing signals cross the logic threshold. This makes it particularly useful for interfacing with analog signals or cleaning up noisy digital signals.

Features

• Six independent Schmitt trigger inverters in a single package
• Standard TTL compatible inputs and outputs
• Hysteresis voltage typically 0.8V at VCC = 4.5V
• Wide operating voltage range: 4.5V to 5.5V
• Typical propagation delay: 15ns at VCC = 5V
• High noise immunity characteristic of Schmitt trigger inputs
• Fan-out of 10 standard TTL loads
• Available in multiple package options including DIP, SOIC, and TSSOP
• Operating temperature range: 0°C to +70°C (commercial grade)

Applications

The 7414 finds use in a wide variety of digital and mixed-signal applications:

• Signal Conditioning: Cleaning up noisy signals before they enter digital systems
• Waveform Shaping: Converting irregular or analog waveforms to clean digital signals
• Pulse Shaping: Improving rise and fall times of digital pulses
• Debouncing Circuits: Eliminating contact bounce in mechanical switches
• Threshold Detection: Creating precise switching points for analog signals
• Oscillator Circuits: Used in relaxation oscillator configurations
• Level Translation: Interfacing between different logic families

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage (VCC): -0.5V to +7V
• DC Input Voltage (VI): -0.5V to VCC + 0.5V
• DC Output Voltage (VO): -0.5V to VCC + 0.5V
• DC Input Diode Current (IIK): ±20mA
• DC Output Diode Current (IOK): ±20mA
• DC Output Current (IO): ±25mA
• DC Supply Current per Input Pin (ICC): ±1mA
• Storage Temperature Range: -65°C to +150°C

Recommended Operating Conditions

• Supply Voltage (VCC): 4.75V to 5.25V
• Input High Voltage (VIH): 2V min
• Input Low Voltage (VIL): 0.8V max
• Operating Temperature Range: 0°C to +70°C

DC Electrical Characteristics (VCC = 5V, TA = 25°C)

• Input Clamp Voltage (VIK): -1.5V max (II = -18mA)
• Output High Voltage (VOH): 2.7V min (IOH = -400μA)
• Output Low Voltage (VOL): 0.4V max (IOL = 16mA)
• Input Current (II): ±1μA max (VI = 5.5V)
• Input Hysteresis Voltage (VH): 0.8V typ (VCC = 4.5V)
• Supply Current (ICC): 12mA max (all inputs at 4.5V)

AC Electrical Characteristics

• Propagation Delay (tPLH, tPHL): 15ns typ, 22ns max (CL = 15pF, RL = 400Ω)
• Output Transition Time (tTLH, tTHL): 10ns typ, 15ns max

Package Information

The 7414 is available in several package options to accommodate different application requirements:

14-Pin DIP (Dual In-line Package)

• Package Code: 646-07
• Dimensions: 19.3mm x 6.35mm x 4.57mm
• Pin Spacing: 2.54mm (0.1") between pins, 7.62mm (0.3") row spacing
• Material: Molded plastic
• Lead Finish: Solder-plated or tin-lead

14-Pin SOIC (Small Outline Integrated Circuit)

• Package Code: 751A-05
• Dimensions: 8.65mm x 3.9mm x 1.5mm
• Pin Spacing: 1.27mm pitch
• Material: Molded plastic
• Lead Finish: Matte tin or lead-free options available

14-Pin TSSOP (Thin Shrink Small Outline Package)

• Package Code: 948F-03
• Dimensions: 5mm x 4.4mm x 1mm
• Pin Spacing: 0.65mm pitch
• Material: Molded plastic
• Lead Finish: Lead-free options available

Pin Configuration and Truth Table

Pin Description

• Pins 1, 3, 5, 9, 11, 13: 1A to 6A (Data Inputs)
• Pins 2, 4, 6, 8, 10, 12: 1Y to 6Y (Data Outputs)
• Pin 7: GND (Ground, 0V reference)
• Pin 14: VCC (Positive Supply Voltage, typically +5V)

Truth Table

• Input (A) Low: Output (Y) High
• Input (A) High: Output (Y) Low

Design Considerations

When using the 7414 in circuit designs, several factors should be considered:

• Power Supply Decoupling: A