MC88916DW70

Overview

The MC88916DW70 is a low skew CMOS PLL clock driver designed for CISC microprocessor and single processor RISC systems. Operating at a maximum 2X_Q output frequency of 70 MHz, it locks multiple outputs to a SYNC input reference. The device features six total outputs: three Q outputs (Q0–Q2) with less than 500 ps skew, an inverted Q3 output, a 2X_Q output running at twice the system frequency, and a Q/2 feedback output. It includes integrated processor reset functionality via RST_IN/RST_OUT pins and TTL-compatible inputs with CMOS/TTL level outputs.

Feature Summary

• Phase-locked loop technology provides low skew distribution (<500ps between Q0-Q2) for 68030/040 microprocessors.
• Six outputs including Q0-Q2, Q3 (180° phase shift), 2X_Q (2x frequency), and Q/2 (internal feedback).
• Integrated RST_IN/RST_OUT(LOCK) pins provide processor reset and phase-lock indication.
• TTL-level compatible inputs with ±36mA drive capability for CMOS or TTL loads.

Applications

• Clock distribution for Motorola 68030 microprocessor family.
• Clock generation for 33 MHz and 40 MHz 68040 microprocessors.
• Single processor RISC system timing solutions.

Procurement Notes

Verify the suffix DW70 indicates the 70 MHz speed grade (MC88916DW70). Confirm package type is 20-SOIC. Check for original manufacturer documentation from Motorola or Freescale/NXP archives as this is a legacy component. Ensure supply voltage matches 5.0V ±10% requirements.

Selection Notes

Select the MC88916DW70 for applications requiring up to 70 MHz 2X_Q output frequency. Choose the MC88916DW80 if 80 MHz operation is needed. Ensure the design accommodates the internal Q/2 feedback loop and requires external pull-up resistors for the open-drain RST_OUT pin. Verify loop filter components match recommended values for stable PLL acquisition.

Part Context

Originally manufactured by Motorola, this part was later managed by Freescale Semiconductor and subsequently NXP. It belongs to the MC88916 series, which also includes the 80 MHz variant (MC88916DW80) and the specialized MC88920 for low-frequency 68040 PCLK/BCLK generation.

Replacement Considerations

The MC88916DW80 is the higher-speed variant within the same family. For specific 68040 low-frequency requirements, the MC88916DW80 or MC88920 may be relevant alternatives depending on duty cycle needs.