NXP Semiconductors MPC755BPX300LE

Overview

MPC755BPX300LE from Freescale Semiconductor is a 300 MHz PowerPC™ RISC microprocessor implementing the 60x bus architecture, featuring a 32 KB instruction and 32 KB data L1 cache, integrated L2 cache controller, and support for 2.0 V core voltage with 2.5 V/3.3 V I/O interface options. It targets low-power embedded systems requiring deterministic real-time execution, such as industrial control and telecom infrastructure.

For engineers reviewing the MPC755BPX300LE datasheet, MPC755BPX300LE pinout, MPC755BPX300LE application, or MPC755BPX300LE equivalent, key selection considerations include its 360-ball CBGA package, 300 MHz core frequency with 100 MHz SYSCLK max, L2 cache interface capability, thermal management assist unit (TAU), and compatibility with MPC750-family software toolchains and system designs.

Technical Context

The MPC755BPX300LE implements a dual-integer-unit, out-of-order execution pipeline with branch prediction (512-entry BHT, 64-entry BTIC), six-entry reorder buffer, and IEEE 754-compliant floating-point unit supporting single/double-precision arithmetic. Its memory subsystem includes hardware-managed 128-entry ITLB/DTLB, eight BATs per domain, and virtual memory support up to 4 exabytes.

It integrates a dedicated L2 cache interface supporting 256 KB–1 MB external synchronous BurstRAMs with configurable line sizes (64/128 bytes), core-to-L2 divisors (÷1 to ÷3), and copy-back/write-through modes. Power management includes doze, nap, and sleep states plus dynamic regulation via on-die thermal sensor and TAU interrupt logic.

Key Specifications

Pinout & Package

Package: 360-ball ceramic ball grid array (CBGA), 27 mm × 27 mm, 1.27 mm pitch, RoHS-compliant. Designed for high-reliability industrial and telecom applications requiring stable thermal cycling performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC755BPX300LE, the MPC745BPX300LE removes L2 interface capability to reduce cost and die size, while the MPC750FXZU300B retains full functionality in a plastic package-offering trade-offs between thermal performance, long-term interconnect reliability, and system-level cooling design constraints.

Availability

MPC755BPX300LE is available at Aetrix Electronics and suitable for industrial motion control, telecom baseband processing, avionics data concentrators, and medical imaging subsystems requiring stable component supply across extended product lifecycles.

Supply support for MPC755BPX300LE 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 processors, analog, and connectivity solutions for automotive, industrial, and networking markets.

The MPC755BPX300LE belongs to the PowerPC 7xx family, designed specifically for high-performance, low-power embedded computing in safety-critical and thermally constrained environments where software compatibility with the MPC750 ecosystem is essential.

FAQ

What is the maximum supported SYSCLK frequency for MPC755BPX300LE?

The MPC755BPX300LE supports a maximum SYSCLK frequency of 100 MHz, as specified in Table 8 of the hardware specifications document. This corresponds to its 300 MHz core frequency using a 3× PLL multiplier. Exceeding 100 MHz violates AC timing specifications and may result in metastability or functional failure. The device's PLL_CFG[0:3] pins must be configured at reset to achieve this ratio, and runtime changes are unsupported.

Does MPC755BPX300LE support both big-endian and little-endian operation?

Yes, the MPC755BPX300LE supports both big-endian and little-endian byte addressing through dedicated MSR[LE] bit control, as documented in the MPC750 Family User's Manual. This capability is implemented in the load/store unit and applies to all memory accesses including cache line fills, TLB translations, and DMA-coherent transfers - enabling flexible integration with heterogeneous peripheral subsystems.

Can MPC755BPX300LE operate with a 1.8 V core supply voltage?

Yes, the MPC755BPX300LE permits core supply voltage down to 1.80 V under recommended operating conditions for 300 MHz operation (Table 3). However, this is a minimum limit-not a nominal value-and requires validated power delivery with ≤100 mV ripple. Operation below 1.80 V risks timing violations and is not characterized or guaranteed by Freescale.

Is the L2 cache interface on MPC755BPX300LE compatible with standard synchronous SRAMs?

Yes, the MPC755BPX300LE L2 interface supports flow-through (register-buffer) and pipelined (register-register) synchronous BurstRAMs, including 3-1-1-1 and strobeless 4-1-1-1 protocols. It does not support asynchronous SRAM or DDR-type interfaces. External SRAM must match the configured line size (64 or 128 bytes) and be wired to the dedicated 17-bit L2 address and 64-bit L2 data buses.

How is thermal monitoring implemented in MPC755BPX300LE?

The MPC755BPX300LE implements thermal monitoring via an on-die thermal sensor feeding a comparator within the Thermal Management Assist Unit (TAU). Raw sensor output is read through special-purpose registers (THRM0–THRM3); software must apply calibration coefficients from AN1800/D to convert values to junction temperature. An interrupt triggers when temperature exceeds programmable thresholds, enabling autonomous throttling or system shutdown.