The MPC9658 utilizes PLL technology to frequency lock its outputs onto an input reference clock. Normal operation of the MPC9658 requires the connection of the QFB output to the feedback input to close the PLL feedback path (external feedback). With the PLL locked, the output frequency is equal to the reference frequency of the device and VCO_SEL selects the operating frequency range of 50 to 125 MHz or 100 to 250 MHz. The two available post-PLL dividers selected by VCO_SEL (divide-by-2 or divide-by-4) and the reference clock frequency determine the VCO frequency. Both must be selected to match the VCO frequency range. The internal VCO of the MPC9658 is running at either 2x or 4x of the reference clock frequency. The MPC9658 has a differential LVPECL reference input along with an external feedback input. The MPC9658 is ideal for use as a zero delay, low skew fanout buffer. The device performance has been tuned and optimized for zero delay performance. The PLL_EN and BYPASS controls select the PLL bypass configuration for test and diagnosis. In this configuration, the selected input reference clock is bypassing the PLL and routed either to the output dividers or directly to the outputs. The PLL bypass configurations are fully static and the minimum clock frequency specification and all other PLL characteristics do not apply. The outputs can be disabled (high-impedance) and the device reset by asserting the MR/OE pin. Asserting MR/OE also causes the PLL to loose lock due to missing feedback signal presence at FB_IN. Deasserting MR/OE will enable the outputs and close the phase locked loop, enabling the PLL to recover to normal operation. The MPC9658 is fully 3.3 V compatible and requires no external loop filter components. The inputs (except PCLK) accept LVCMOS except signals while the outputs provide LVCMOS compatible levels with the capability to drive terminated 50 ? transmission lines. For series terminated transmission lines, each of the MPC9658 outputs can drive one or two traces giving the devices an effective fanout of 1:16. The device is packaged in a 7x7 mm2 32-lead LQFP package.


  • Low based low-voltage clock generator
  • Supports zero-delay operation
  • 3.3 V power supply
  • Generates clock signals up to 250 MHz
  • Maximum output skew of 120 ps
  • Differential LVPECL reference clock input
  • External PLL feedback
  • Drives up to 20 clock lines
  • 32-lead LQFP packaging
  • 32-lead Pb-free Package Available
  • Pin and function compatible to the MPC958

Product Options

Orderable Part ID Part Status Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Obsolete 32 C Yes Tray

Documentation & Downloads

Title Other Languages Type Format File Size Date
Datasheets & Errata
MPC9658 Datasheet Datasheet PDF 573 KB
Application Notes & White Papers
AN-828 Termination - LVPECL Application Note PDF 322 KB
AN-831 The Crystal Load curve Application Note PDF 395 KB
AN-845 Termination - LVCMOS Application Note PDF 146 KB
AN-844 Termination - AC Coupling Clock Receivers Application Note PDF 170 KB
AN-842 Thermal Considerations in Package Design and Selection Application Note PDF 495 KB
AN-803 Crystal Timing Budget and Accuracy for IDT Timing Clock Products Application Note PDF 128 KB
AN-840 Jitter Specifications for Timing Signals Application Note PDF 442 KB
AN-838 Peak-to-Peak Jitter Calculations Application Note PDF 115 KB
AN-839 RMS Phase Jitter Application Note PDF 233 KB
AN-832 Timing Budget and Accuracy Application Note PDF 131 KB
AN-833 Differential Input Self Oscillation Prevention Application Note PDF 180 KB
AN-834 Hot-Swap Recommendations Application Note PDF 153 KB
AN-836 Differential Input to Accept Single-ended Levels Application Note PDF 120 KB
AN-835 Differential Input with VCMR being VIH Referenced Application Note PDF 160 KB
AN-830 Quartz Crystal Drive Level Application Note PDF 143 KB
AN-827 Application Relevance of Clock Jitter Application Note PDF 1.15 MB
AN-815 Understanding Jitter Units Application Note PDF 565 KB
AN-802 Crystal-Measuring Oscillator Negative Resistance Application Note PDF 136 KB
AN-801 Crystal-High Drive Level Application Note PDF 202 KB
AN-806 Power Supply Noise Rejection Application Note PDF 438 KB
AN-805 Recommended Ferrite Beads Application Note PDF 121 KB
PCN# : A1401-02 Alternate Copper Wire Assembly Site Product Change Notice PDF 36 KB
PDN# : N-12-48 PRODUCT DISCONTINUANCE NOTICE Product Discontinuation Notice PDF 93 KB
PDN# N-10-04 Product Discontinuation Notice PDF 100 KB
PCN# : A-0610-02 ASAT China as Alternate Facility for CABGA/CVBGA/FPBGA/TQFP/PQFP Product Change Notice PDF 252 KB
MPC9658 IBIS Model Model - IBIS ZIP 18 KB