NXP Semiconductors MC7457RX1000LC

Overview

MC7457RX1000LC from Freescale Semiconductor is a 1.0 GHz PowerPC G4 RISC microprocessor with 512-Kbyte on-die L2 cache, 1.3-V core supply, and support for 1–4 MB external L3 SRAM via dedicated high-bandwidth interface. It implements full 32-bit PowerPC architecture with AltiVec SIMD unit, double-precision FPU, and superscalar seven-stage pipeline - deployed in high-performance networking and computing systems requiring deterministic real-time processing.

For engineers reviewing the MC7457RX1000LC datasheet, MC7457RX1000LC pinout, MC7457RX1000LC application, or MC7457RX1000LC equivalent, key selection considerations include L3 interface voltage configuration (1.5/1.8/2.5 V), MPX/60x bus protocol compatibility, thermal resistance (RθJA = 20°C/W), L2 cache latency (9-cycle L1 miss → L2 hit), and footprint compatibility with MPC7455 at 1.3-V core.

Technical Context

The MC7457RX1000LC integrates a superscalar core with four integer units, five-stage FPU, and four vector units supporting AltiVec instructions. Its memory subsystem uses separate instruction/data MMUs with 128-entry two-way TLBs, 32-Kbyte L1 caches (8-way set associative), and a fully pipelined 512-Kbyte unified L2 cache delivering 32 bytes/cycle to L1.

L3 interface operates at configurable core-to-L3 frequency divisors with 64-bit data bus, supports MSUG2 DDR/PB2/LW synchronous burst SRAMs, and enables private memory allocation (up to 2 MB of 4-MB total SRAM). Power management includes Nap/Sleep/Deep Sleep modes controlled via JTAG/COP interface and thermal exception handling.

Key Specifications

Pinout & Package

MC7457RX1000LC uses a 483-ball ceramic ball grid array (CBGA) package with 1.27 mm pitch, designed for high-density routing and thermal dissipation in demanding embedded computing applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC7455EC and MPC7447A, MC7457RX1000LC provides higher clock rate (1.0 GHz), larger L2 cache (512 KB), and unique L3 interface - making it optimal for applications requiring sustained bandwidth to external SRAM, while MPC7455EC and MPC7447A serve lower-power or space-constrained alternatives without L3 dependency.

Availability

MC7457RX1000LC is available at Aetrix Electronics and suitable for network router control planes, medical imaging workstations, avionics data concentrators, and high-end print controllers requiring stable component supply across extended product lifecycles.

Supply support for MC7457RX1000LC 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 MPC7457 belongs to Freescale's PowerPC G4 microprocessor family, designed specifically for high-performance embedded computing applications demanding AltiVec acceleration, large on-die cache, and deterministic real-time behavior in networking and signal processing systems.

FAQ

What is the maximum operating frequency of the MC7457RX1000LC?

The MC7457RX1000LC is rated for a fixed maximum operating frequency of 1.0 GHz. This speed is guaranteed under recommended operating conditions including 1.3 V ±50 mV core supply, 105°C maximum junction temperature, and proper decoupling. The device does not support frequency scaling beyond this rating, and overclocking is not supported or characterized.

Does the MC7457RX1000LC support L3 cache configuration with 4 MB of external SRAM?

Yes, the MC7457RX1000LC supports up to 4 MB of total external SRAM via its L3 interface, but only 2 MB may be configured as cache memory; the remaining 2 MB must be allocated as private memory or left unused. This constraint is enforced by the internal L3 cache controller and documented in the hardware specification Rev. 8.

What are the valid I/O voltage configurations for the MC7457RX1000LC processor bus?

The MC7457RX1000LC processor bus supports two I/O voltage configurations: 1.8 V ±5% (BVSEL = 0) or 2.5 V ±5% (BVSEL = HRESET or OVDD). These settings are latched at ¬HRESET and determine both input thresholds and output drive levels - mixing voltages within one bus is not permitted.

Is the MC7457RX1000LC pin-compatible with the MPC7455?

Yes, the MC7457RX1000LC is footprint-compatible and functions as a drop-in replacement for the MPC7455 in applications using a 1.3-V core supply. However, differences in L2 cache size (512 KB vs 256 KB) and L3 interface presence require validation of timing margins and software cache management routines before substitution.

What thermal management features does the MC7457RX1000LC provide?

The MC7457RX1000LC includes hardware-enforced thermal management via three supervisor-level registers and a dedicated thermal management exception. It supports instruction cache throttling, Nap/Sleep/Deep Sleep power modes, and software-controllable thermal shutdown - all accessible through the MPC7457-specific thermal management unit referenced in the hardware specification.