NXP Semiconductors MPC9229FN

Overview

MPC9229FN from Freescale Semiconductor (formerly Motorola) is a 3.3 V, SiGe-based PLL clock synthesizer with differential LVPECL outputs, supporting 25–400 MHz synthesized frequencies via on-chip crystal oscillator and programmable M/N dividers. It delivers sub-nanosecond edge rates for telecom backplane timing and high-speed serial link clocking.

For engineers reviewing the MPC9229FN datasheet, MPC9229FN pinout, MPC9229FN application, or MPC9229FN equivalent, key selection criteria include its 800–1600 MHz VCO range, dual serial/parallel programming interfaces, LVCMOS-compatible control inputs, and separate VCC_PLL supply for jitter-sensitive PLL operation.

Technical Context

The MPC9229FN implements a fully integrated PLL with internal crystal oscillator (10–20 MHz XTAL), 16× reference divider, 4× PLL multiplier, and post-divider N = 1/2/4/8. Its VCO operates at 800–1600 MHz, and output frequency is calculated as fOUT = (fXTAL ÷ 16) × M ÷ N, where M is a 9-bit feedback divider (0–511) and N is a 2-bit post-divider.

It features dual configuration paths: parallel loading via M[8:0] and N[1:0] pins synchronized to P_LOAD, and serial 14-bit shift register programming via S_DATA/S_CLOCK/S_LOAD. The TEST pin supports diagnostic visibility into internal nodes (e.g., FOUT, M-counter, PLL-bypass mode) but must remain static during normal operation to meet jitter specs.

Key Specifications

Pinout & Package

Package: 28-lead PLCC (Case 776), body size 11.43 mm × 11.43 mm × 2.29 mm, lead pitch 1.27 mm, surface-mount compatible.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar clock synthesizer applications.

Compared with MC12429, MPC9229FN offers lower jitter and reduced power via SiGe process while maintaining full pin compatibility; compared with ICS843001AGI-01LFT, it trades EEPROM convenience and LVDS flexibility for on-chip crystal support and PECL drive strength essential in high-noise telecom backplanes.

Availability

MPC9229FN is available at Aetrix Electronics and suitable for telecom infrastructure, high-speed networking, and server memory subsystems requiring stable component supply with long-term lifecycle assurance.

Supply support for MPC9229FN includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Freescale Semiconductor (now part of NXP Semiconductors) is a global leader in high-performance analog and mixed-signal semiconductors, with deep expertise in timing, RF, and power management solutions.

The MPC9229FN belongs to Freescale's Timing Solutions product line, designed specifically for low-jitter clock generation in demanding telecom, computing, and networking systems where signal integrity and phase stability are critical.

FAQ

What is the maximum output frequency supported by the MPC9229FN?

The MPC9229FN supports a maximum output frequency of 400 MHz when configured with N = 1 (÷1 post-divider) and appropriate M value. This occurs with crystal frequencies between 10–20 MHz and M values ensuring the VCO remains within its 800–1600 MHz operating range. For example, using a 16 MHz crystal, M = 400 yields fOUT = (16 MHz ÷ 16) × 400 ÷ 1 = 400 MHz. The MPC9229FN datasheet confirms this limit in Table 6 under fMAX.

Does the MPC9229FN require external load capacitors for the crystal oscillator?

No, the MPC9229FN does not require external load capacitors. Its on-chip crystal oscillator uses a series-resonant topology optimized for AT-cut fundamental-mode crystals with 5–7 pF shunt capacitance, as specified in Table 11. External capacitors would degrade stability and increase jitter. The MPC9229FN datasheet explicitly states "no external load caps required" and recommends mounting the crystal as close as possible to minimize parasitics.

Can the TEST pin of the MPC9229FN be left unconnected in production designs?

No, the TEST pin of the MPC9229FN must not be left floating. It has an internal pull-down but is actively driven during configuration and diagnostic modes. To guarantee jitter specifications (≤190 ps cycle-to-cycle), the TEST pin must be held static-either tied to VCC or GND-or configured via serial interface to a non-switching state (e.g., T[2:0] = 001 or 101). Leaving it unconnected risks unintended toggling that couples noise into the PLL, degrading MPC9229FN performance.

What is the purpose of the separate VCC_PLL supply pin on the MPC9229FN?

The VCC_PLL pin provides a dedicated 3.3 V supply exclusively for the analog PLL circuitry, isolating it from digital switching noise on the main VCC rail. This separation reduces power-supply-induced jitter, enabling the MPC9229FN to achieve its specified sub-200 ps cycle-to-cycle jitter. The MPC9229FN datasheet specifies VCC_PLL current ≤20 mA and recommends RC filtering (e.g., 10–15 Ω resistor + 22 µF capacitor) to suppress 1 kHz–1 MHz noise.

How does the MPC9229FN handle output enable (OE) functionality?

The MPC9229FN implements synchronous OE (active-high) that gates the FOUT/FOUT outputs without generating runt pulses. When OE is low, both outputs are forced to defined logic states (FOUT = L, FOUT = H), eliminating metastability. This behavior is confirmed in Table 1 and the Functional Description section of the MPC9229FN datasheet. Unlike asynchronous enable schemes, the MPC9229FN's OE is edge-aligned to the output clock domain, making it safe for hot-plug and power-management applications.