NXP Semiconductors MPC855TVR50D4

Overview

MPC855TVR50D4 from NXP (formerly Freescale) is a PowerQUICC™ integrated communications processor combining a 32-bit Power Architecture™ core and a RISC-based Communications Processor Module (CPM) in a single PBGA357 package. It delivers 50 MHz CPU operation, 4 KB instruction/4 KB data cache, IEEE 802.3 10-Mbps Ethernet on SCC1–4, HDLC/SDLC up to 2 Mbps per channel, and UTOPIA-level ATM support. It targets embedded networking control in DSLAMs, industrial gateways, and telecom edge devices.

For engineers reviewing the MPC855TVR50D4 datasheet, MPC855TVR50D4 pinout, MPC855TVR50D4 application, or MPC855TVR50D4 equivalent, this page provides verified technical context, validated pin functions, real-world use cases, and two confirmed alternative parts with documented functional and packaging differences for design-in evaluation.

Technical Context

The MPC855TVR50D4 implements a dual-core architecture: a 32-bit Power Architecture CPU with MMU, 4/4 KB caches, and a separate RISC CPM handling serial protocols (HDLC, UART, I²C, SPI, SMC) without CPU intervention. Its memory controller supports eight banks with programmable wait states and glueless interface to DRAM, SRAM, Flash, and EPROM.

It integrates four Serial Communication Controllers (SCCs), two Serial Management Channels (SMCs), one SPI, one I²C port, four baud-rate generators, a time-slot assigner (TSA), PCMCIA socket controller, and real-time clock. The device operates at 3.3 V with 5-V-tolerant I/O (except EXTAL/EXTCLK) and supports low-power modes including Doze, Sleep, and Deep Sleep.

Key Specifications

Pinout & Package

Package: 357-pin Plastic Ball Grid Array (PBGA), ZQ/VR designation (Case No. 5058), 25 mm × 25 mm body, 1.27 mm ball pitch, 1.2 mm height. Thermal pad on underside requires solder connection to PCB ground plane for optimal heat dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar communications processor applications.

Compared with MPC860T, MPC855TVR50D4 offers lower thermal load and simpler power delivery at the cost of raw throughput; compared with MPC855T, it shares identical electrical behavior but reflects an earlier production mask - both alternatives retain full pin and software compatibility.

Availability

MPC855TVR50D4 is available at Aetrix Electronics and suitable for DSLAM line cards, industrial protocol gateways, telecom edge routers, and secure RTUs requiring stable component supply across extended product lifecycles.

Supply support for MPC855TVR50D4 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

NXP Semiconductors (formerly Freescale Semiconductor) is a global leader in secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in Power Architecture™ and communications processors.

The MPC855T series belongs to the PowerQUICC™ family - designed specifically for cost-sensitive, low-power embedded networking applications requiring integrated protocol acceleration and deterministic real-time response.

FAQ

What is the maximum operating frequency of the MPC855TVR50D4?

The MPC855TVR50D4 is factory-configured for a fixed 50 MHz CPU clock frequency. It does not support overclocking or frequency scaling beyond this rating. Bus operation runs synchronously at 50 MHz (1:1 mode), and the device's DC specifications mandate 3.135–3.465 V supply voltage to guarantee stable operation at this speed. Attempting to run above 50 MHz violates the published electrical characteristics and may cause timing violations or data corruption in the MPC855TVR50D4.

Does the MPC855TVR50D4 support 100-Mbps Ethernet?

No, the MPC855TVR50D4 does not support 100-Mbps Ethernet. Its SCC peripherals are qualified only for 10-Mbps IEEE 802.3 operation, and this capability requires special factory programming. The MPC855TVR50D4 lacks the MII or RMII physical layer interface logic needed for Fast Ethernet, and its internal timing paths are not characterized for 100 Mbps signaling. For 100-Mbps support, engineers must select the MPC860 family (e.g., MPC860T) or later PowerQUICC II devices.

What package type and thermal characteristics apply to the MPC855TVR50D4?

The MPC855TVR50D4 uses a 357-ball PBGA package with ZQ/VR designation (Case No. 5058), measuring 25 mm × 25 mm with 1.27 mm pitch. Its thermal resistance is RθJA = 34°C/W on a single-layer board and RθJB = 13°C/W to the PCB - confirming primary heat transfer occurs through the bottom thermal pad. The device's maximum junction temperature is 95°C, and operation above this threshold risks permanent damage to the MPC855TVR50D4.

Can the MPC855TVR50D4 be used as a drop-in replacement for the MPC855T?

Yes, the MPC855TVR50D4 is a direct drop-in replacement for the MPC855T. Both share identical pinout, electrical specifications, timing parameters, and mask revision D4. The "VR" suffix denotes the ZQ/VR package variant (1.2 mm height), while standard MPC855T parts may use ZP (0.9 mm). Mechanical fit is guaranteed within PBGA357 footprint tolerances, and no firmware or hardware changes are required when substituting MPC855TVR50D4 for MPC855T in existing designs.

What debug capabilities does the MPC855TVR50D4 provide for embedded development?

The MPC855TVR50D4 includes an IEEE 1149.1 (JTAG) test access port and eight hardware watchpoint comparators - four for instruction address, two for data address, and two for data value matching. These enable non-intrusive breakpoints, data change monitoring, and real-time trace without halting the CPU. The MPC855TVR50D4 also supports advanced on-chip emulation (OCE) mode, allowing full visibility into both CPU and CPM execution states during development and validation.