The UPD74HC4538GS is a retriggerable precision monostable multivibrator with CMOS technology manufactured by NEC. This device can be used in timing circuits to produce accurate time delays, pulse width generation, or as a frequency discriminator.

Applications

• Timing Circuits: Creating precise time delays for various applications.
• Pulse Width Modulation (PWM): Generating PWM signals for motor control and other applications.
• Missing Pulse Detection: Detecting the absence of pulses in a pulse train.
• Touch Tone Decoding: Decoding touch tone signals in telephone systems.
• Frequency Discrimination: Distinguishing between different frequencies.

Features

• Retriggerable Monostable Multivibrator: Can be retriggered before the output pulse has completed.
• CMOS Technology: Provides high noise immunity and low static power dissipation.
• Wide Operating Voltage Range: Operates over a wide range of supply voltages (2V to 6V).
• Precision Timing: Offers accurate and stable timing characteristics.
• Adjustable Pulse Width: The output pulse width can be adjusted using external resistors and capacitors.
• Low Power Consumption: Consumes minimal power, making it suitable for battery-powered applications.
• Trigger Inputs: Both positive and negative edge trigger inputs are available.

Benefits

• Versatile Timing Solution: Can be used for a wide variety of timing applications.
• Precise and Stable Timing: Provides accurate and reliable timing characteristics.
• Energy Efficiency: Low power consumption contributes to energy savings.
• Easy Adjustment: The output pulse width can be easily adjusted using external components.
• Reliable Operation: CMOS technology ensures reliable operation in noisy environments.

Additional Details

The UPD74HC4538GS triggers on either the positive or negative edge of the input signal, depending on the connection of the trigger inputs. The output pulse width is determined by the values of an external resistor (Rext) and capacitor (Cext) connected to the timing pins. The output pulse width is approximately equal to Rext * Cext.

This device is commonly available in a SOIC (Small Outline Integrated Circuit) package.