MC74HC4538AF

Multivibrators Overview

The MC74HC4538AF is a dual precision monostable multivibrator manufactured by onsemi. It operates within a supply voltage range of 3.0 to 6.0 V and features retriggerable and resettable functionality. The device accepts positive-edge triggers at input A and negative-edge triggers at input B, with no restrictions on trigger input rise or fall times. Output pulse width is determined by external timing components Rx and Cx, offering ±10% guaranteed variation. It provides an output drive capability of 10 LSTTL loads and interfaces directly with CMOS, NMOS, and TTL logic families.

Multivibrators Feature Summary

• Retriggerable operation allows the output pulse to be extended by subsequent trigger signals during the timing cycle.
• Conditioned trigger inputs eliminate restrictions on input signal rise and fall times for reliable triggering.
• Active-low reset function forces the Q output low and the Q not output high regardless of the current pulse state.
• Outputs are compatible with standard CMOS, NMOS, and TTL logic levels.

Multivibrators Applications

• Pulse generation and shaping in digital circuits
• Timing delay applications requiring precise duration control
• Debouncing switches or contacts in microcontroller systems

Multivibrators Procurement Notes

Verify the specific suffix AF corresponds to the SOEIAJ-16 package configuration required for your design. Confirm that the ordering information matches the desired shipping quantity, such as rails or reels, as specified in the manufacturer's documentation. Ensure compatibility with your system's voltage and temperature requirements before finalizing procurement.

Multivibrators Selection Notes

Select this component when a dual monostable multivibrator with retriggerable capabilities is needed. It is suitable for designs requiring independent timing for two channels using external resistors and capacitors. Consider its HC logic family characteristics for speed and power consumption relative to other available options.

Multivibrators Part Context

This device belongs to the 74HC series of high-speed CMOS logic integrated circuits. It is pin-compatible with older CD4528 and CD4538 devices but offers improved performance characteristics typical of the HC technology. The MC74HC4538A variant serves as the base model for various packaging options including SOIC, TSSOP, and SOEIAJ.

Multivibrators Replacement Considerations

The datasheet notes pin compatibility with the CD4528 and CD4538. Verify electrical specifications against these alternatives if substituting in existing designs.

Multivibrators FAQ

Can the MC74HC4538AF be triggered by both rising and falling edges?

Yes, it can be triggered by a rising edge at input A or a falling edge at input B.

What determines the output pulse width?

The output pulse width is determined by the values of the external timing resistor (Rx) and capacitor (Cx).