CD74HCT7046AMT

Overview

The CD74HCT7046AMT is a high-speed CMOS phase-locked loop (PLL) integrated circuit manufactured by Texas Instruments. It integrates a voltage-controlled oscillator (VCO), two phase detectors, and a lock detector within a single package. The device operates on a supply voltage range of 4.5 V to 5.5 V and supports maximum input frequencies up to 38 MHz. It is housed in a 16-pin TSSOP surface-mount package and functions reliably across an industrial temperature range from -55°C to +125°C.

Feature Summary

• Integrates a wide-range voltage-controlled oscillator (VCO) capable of covering multiple frequency bands without external tuning components.
• Includes dual phase detectors: a digital XOR type for low-frequency applications and an edge-triggered type for higher frequency operation.
• Features an internal lock detector that provides a logic output indicating when the PLL has achieved frequency synchronization.

Applications

• Frequency synthesis systems requiring stable clock generation.
• Demodulation circuits for FM or PM signals.
• Clock recovery circuits in data communication interfaces.

Procurement Notes

Verify the suffix 'T' indicates tape-and-reel packaging rather than tube packaging when ordering. Confirm the HCT logic family compatibility with 5V TTL inputs if interfacing with legacy digital systems. Ensure the TSSOP-16 footprint matches the PCB design constraints. Check RoHS compliance status as per the specific manufacturing batch documentation.

Selection Notes

Select this component over HC variants when strict 5V logic level compatibility with TTL inputs is required. The HCT series ensures proper voltage threshold matching for standard 5V digital environments. Consider the TSSOP package size constraints against available board space. Verify thermal dissipation requirements given the operating temperature range limits.

Part Context

This part belongs to the CD74HCT7046A family of phase-locked loops. It shares functional architecture with the CD74HC7046A but utilizes HCT technology for improved noise immunity and direct compatibility with 5V TTL logic levels. The 'T' suffix specifically denotes the reel packaging format for automated assembly processes.

Replacement Considerations

CD74HC7046AMT

FAQ

What is the difference between the two phase detectors included in this IC?

The IC includes an exclusive OR (XOR) phase detector suitable for lower frequency applications and an edge-triggered phase detector designed for higher frequency operations up to 38 MHz.

Does the CD74HCT7046AMT require external components for the VCO?

Yes, the voltage-controlled oscillator (VCO) requires external timing resistors and capacitors to set the oscillation frequency range.