NXP Semiconductors MC7448HX1267NC

Overview

MC7448HX1267NC from Freescale Semiconductor is a 1700 MHz PowerPC G4 RISC microprocessor with integrated 1-Mbyte unified L2 cache, dual-precision FPU, and AltiVec SIMD engine, designed for high-performance networking and computing systems requiring deterministic real-time processing, hardware cache coherency, and dynamic frequency scaling. It implements PowerPC ISA v1.0 on 90 nm SOI CMOS and supports MPX/60x bus protocols.

For engineers reviewing the MC7448HX1267NC datasheet, MC7448HX1267NC pinout, MC7448HX1267NC application, or MC7448HX1267NC equivalent, key selection criteria include core voltage (1.30 V ±20/–50 mV), I/O voltage mode flexibility (1.5/1.8/2.5 V), thermal diode integration, DFS support (÷2/÷4), and L2 ECC capability - all critical for telecom control plane, embedded server, and signal processing designs.

Technical Context

The MC7448HX1267NC employs a seven-stage superscalar pipeline with out-of-order issue for AltiVec instructions and in-order execution for scalar floating-point and vector units. Its memory subsystem features separate 32-Kbyte 8-way set-associative L1 instruction and data caches with MESI coherency, plus an on-die 1-Mbyte 8-way unified L2 cache supporting ECC or parity on data and parity on tags.

It integrates dual MMUs (128-entry 2-way TLBs), JTAG/COP debug interface, hardware-enforced cache coherency, load/store reservation for atomic operations, and three power-saving modes (Nap, Sleep, Deep Sleep) with PLL retention and SYSCLK gating - enabling precise thermal management in dense compute environments.

Key Specifications

Pinout & Package

MC7448HX1267NC is housed in a surface-mount 360-pin ceramic ball grid array (HCTE) package measuring 37.5 mm × 37.5 mm with 1.27 mm pitch. The package supports thermal dissipation via exposed thermal pad and is qualified for industrial temperature range (0°C to 105°C junction).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RISC microprocessor applications.

Compared with MPC7447AHX1267NC and MPC7450CZQ1267C, MC7448HX1267NC uniquely balances 1700 MHz performance, L2 ECC integrity, DFS-enabled thermal adaptability, and BGA packaging - making it optimal for space-constrained, air-cooled telecom and industrial compute platforms requiring long-term component stability.

Availability

MC7448HX1267NC is available at Aetrix Electronics and suitable for telecom infrastructure, embedded server, and ruggedized industrial control applications requiring stable component supply, long-lifecycle support, and traceable sourcing from original manufacturer channels.

Supply support for MC7448HX1267NC 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 fabless semiconductor company specializing in embedded processing, connectivity, and analog solutions for automotive, industrial, and networking markets.

The MPC7448 product line was engineered for high-throughput, low-latency control-plane processing in carrier-class networking equipment and real-time embedded computing systems demanding PowerPC ISA compliance and hardware reliability features.

FAQ

What is the maximum operating junction temperature for MC7448HX1267NC?

The MC7448HX1267NC has a maximum rated die-junction temperature of 105°C under natural convection on a four-layer board (RθJMA = 19°C/W). This limit applies during Full-Power Mode–Thermal operation and must be maintained using appropriate heatsinking and airflow per JEDEC JESD51-6. Exceeding 105°C risks thermal shutdown or permanent damage to the MC7448HX1267NC.

Does MC7448HX1267NC support pin-compatible migration from MPC7447A devices?

MC7448HX1267NC shares identical pinout and package dimensions with MPC7447A variants, enabling mechanical drop-in replacement. However, BVSEL[0:1] configuration for 1.8 V I/O mode differs - requiring board-level modification. The 2.5 V mode remains fully pin-compatible. Firmware must enable DFS and configure L2 ECC registers not present in MPC7447A, so software validation is required for MC7448HX1267NC deployment.

How does the L2 cache ECC implementation work on MC7448HX1267NC?

The MC7448HX1267NC implements 64-bit ECC protection on L2 data and byte-level parity on L2 tags. ECC correction is automatic for single-bit errors and detectable for double-bit errors, with error injection capability for software recovery testing. This ECC functionality is enabled via SPR writes and requires system software to handle uncorrectable errors - a key reliability feature distinguishing MC7448HX1267NC from non-ECC L2 predecessors.

What power supply sequencing is required for reliable MC7448HX1267NC startup?

MC7448HX1267NC requires strict power sequencing: OVDD must be stable before VDD and AVDD ramp; VDD and AVDD must track within ±50 mV during ramp-up; and HRESET must remain asserted until all supplies reach regulation. Violating this sequence risks latch-up or undefined boot behavior. The MC7448HX1267NC datasheet (Section 9.2) specifies exact timing windows and voltage tolerances for each rail transition.

Can MC7448HX1267NC operate in little-endian mode for legacy x86 compatibility?

Yes, MC7448HX1267NC supports both big-endian and little-endian operation modes, including misaligned little-endian accesses, controlled via MSR[LE] bit. This enables binary compatibility with certain legacy toolchains and simplifies porting of Linux distributions targeting heterogeneous architectures. The mode is configurable per-process and does not affect AltiVec vector alignment rules, which remain quad-word aligned regardless of endianness setting in MC7448HX1267NC.