MC88915TFN100R2

Clock Generators, PLLs, Frequency Synthesizers Overview

The MC88915TFN100R2 is a low skew CMOS PLL clock driver manufactured by NXP USA Inc. (formerly Motorola). It operates at a maximum frequency of 100 MHz on the 2X_Q output and 50 MHz on Q outputs, with a supply voltage range of 4.75V to 5.25V. The device provides five phase-locked outputs (Q0–Q4) with less than 500 ps skew, an inverted Q5 output, a doubled frequency 2X_Q output, and a divided Q/2 output. Packaged in a 28-lead PLCC, it supports TTL inputs and CMOS/TTL outputs with ±36 mA drive capability.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Phase-locked loop technology for zero-delay distribution with <500 ps output-to-output skew
• Configurable frequency ratios (1:2, 1:1, 2:1) via FREQ_SEL pin and feedback selection
• Outputs include five locked Q channels, one inverted Q5, one 2X_Q, and one Q/2
• Test mode support via PLL_EN pin and dual SYNC inputs for board-level diagnostics

Clock Generators, PLLs, Frequency Synthesizers Applications

• High-performance PC and workstation clock distribution
• Synchronous multi-board system clocking
• Low skew timing for high-speed digital logic

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify component status as this part number may be discontinued or superseded. Confirm that the 'FN' suffix corresponds to the plastic PLCC package and 'R2' indicates tape and reel packaging. Ensure compatibility with existing 5V power rails and check for RoHS compliance requirements against the datasheet's historical manufacturing standards.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select the TFN100 variant specifically when a 100 MHz 2X_Q output is required. Verify that the input reference clock falls within the allowable SYNC range based on the chosen feedback configuration. Ensure the application environment stays within the -40°C to +85°C temperature range specified for this version.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to the MC88915T family, which includes variants rated for 55, 70, 133, and 160 MHz. The TFN100R2 designation identifies the specific 100 MHz speed grade, FN plastic PLCC package, and reel packaging format. It is part of the legacy 88915 series designed for high-performance computing applications.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Consider evaluating other members of the MC88915T family (e.g., TFN133, TFN160) if higher frequencies are needed, or the MC88LV915T for 3.3V operation.

Clock Generators, PLLs, Frequency Synthesizers FAQ

What is the maximum operating frequency for the Q outputs?

The maximum operating frequency for the Q0–Q4 and Q5 outputs is 50 MHz.

How does the FREQ_SEL pin affect the VCO operation?

Holding FREQ_SEL low enables divide-by-2 in the feedback path, allowing the VCO to run in its optimal range (>20 MHz) even with lower frequency reference clocks.

What is the function of the LOCK output pin?

The LOCK output goes high when the loop achieves steady-state phase and frequency lock, indicating proper operation. It goes low if phase-lock is lost or if PLL_EN is low.