MPC9817ENR2

Overview

The MPC9817ENR2 is a PLL-based clock generator designed for PowerQUICC and PowerPC microprocessor applications. It generates system clocks at selectable frequencies of 25, 33, 50, or 66 MHz using a 25 MHz reference input from an external source or on-chip crystal oscillator. The device provides five LVCMOS processor outputs and three buffered 25 MHz reference outputs. Operating with a 3.3V supply within the -40°C to +85°C temperature range, it features low cycle-to-cycle jitter (150 ps) and output skew (100 ps). Packaged in a 20-lead SSOP, it supports computing, networking, and telecommunications environments.

Feature Summary

• Configurable output frequencies: 25, 33, 50, or 66 MHz via FSEL pins
• Eight total LVCMOS outputs: five configurable processor clocks and three fixed 25 MHz references
• Integrated Pierce oscillator supporting 25 MHz parallel resonant crystals without external components
• Low jitter performance: 150 ps cycle-to-cycle and 100 ps period jitter

Applications

• PowerQUICC and PowerPC microprocessor clock generation
• PCI bus clock generation (33/66 MHz)
• Telecommunications and networking equipment
• Ethernet PHY clock sourcing

Procurement Notes

Verify component authenticity as the original manufacturer, Freescale Semiconductor, was acquired by Integrated Device Technology (IDT), which was subsequently acquired by Renesas Electronics Corporation. Confirm that the EN suffix indicates a lead-free package variant compatible with RoHS standards. Ensure the 20-SSOP package dimensions match the CASE 1461-01 specification during mechanical integration.

Selection Notes

Select this component when designing systems requiring specific PCI bus frequencies (33/66 MHz) for Power architecture processors. The device requires a 25 MHz reference; ensure the design accommodates either an external 25 MHz signal or a 25 MHz crystal with CL=10 pF load capacitance. Verify that the 3.3V ±5% supply voltage aligns with the system power rails and that the LVCMOS output drive strength meets the fan-out requirements of the target logic.

Part Context

The MPC9817 belongs to the IDT NetCOM family of advanced clock drivers originally developed by Freescale Semiconductor's Timing Solutions Organization. Following corporate acquisitions, intellectual property rights transferred through IDT to Renesas Electronics Corporation. This part represents a specialized timing solution for legacy embedded processing architectures rather than general-purpose consumer electronics.

Replacement Considerations

Direct functional replacements are limited due to proprietary frequency synthesis configurations. Review current Renesas timing portfolios for similar PLL-based generators if redesigning. Cross-reference with IDT legacy part numbers to identify pin-compatible alternatives, noting that newer generations may offer differential outputs or lower jitter specifications not present in this single-ended LVCMOS device.

FAQ

How is the output frequency configured?

The output frequency is set by the logic levels on the FSEL0 and FSEL1 pins. Configurations yield 25 MHz (both low), 33 MHz (FSEL0 low, FSEL1 high), 50 MHz (FSEL0 high, FSEL1 low), or 66 MHz (both high).

What are the crystal requirements for the internal oscillator?

The device supports a 25 MHz AT-cut parallel resonant crystal with a load capacitance (CL) of 10 pF. No additional external capacitors are required, though they may be added to XTAL_IN/OUT for fine-tuning.

Can the device operate with an external clock source?

Yes. An external 25 MHz reference can be applied to the XTAL_IN pin. In this mode, the XTAL_OUT pin must be left floating to disable the internal oscillator.