MPC9658 Datasheet, PDF (1/12 Pages) Motorola, Inc – 3.3V 1:10 LVCMOS PLL Clock Generator

MOTOROLA
Freescale Semiconductor, Inc.
Order Number: MPC9658/D
SEMICONDUCTOR TECHNICAL DATA
Rev 3, 02/2003
3.3V 1:10 LVCMOS PLL Clock
Generator
MPC9658
The MPC9658 is a 3.3V compatible, 1:10 PLL based clock generator
and zero-delay buffer targeted for high performance low-skew clock
distribution in mid-range to high-performance telecom, networking and
computing applications. With output frequencies up to 250 MHz and
output skews less than 120 ps the device meets the needs of the most
demanding clock applications. The MPC9658 is specified for the
temperature range of 0°C to +70°C.
LOW VOLTAGE
3.3V LVCMOS 1:10
Features
• 1:10 PLL based low-voltage clock generator
PLL CLOCK GENERATOR
• Supports zero-delay operation
• 3.3V 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
• Pin and function compatible to the MPC958
Functional Description
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.
FA SUFFIX
32 LEAD LQFP PACKAGE
CASE 873A
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 3.3V compatible and requires no external loop filter components. The inputs (except PCLK) accept
W 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.
© Motorola, Inc. 2003
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