NXP Semiconductors MPC8255ACZUMHBB

Overview

MPC8255ACZUMHBB from NXP (formerly Freescale) is a PowerQUICC™ II integrated communications processor featuring a dual-issue EC603e core running up to 266 MHz, 16 KB instruction and 16 KB data caches, and a dedicated Communications Processor Module (CPM) with four SCCs, two SMCs, one SPI, one I²C, two FCCs, one MCC2, and four TDM ports. It targets telecom edge routers, industrial gateways, and legacy DSLAM line cards requiring deterministic real-time protocol offload.

For engineers reviewing the MPC8255ACZUMHBB datasheet, MPC8255ACZUMHBB pinout, MPC8255ACZUMHBB application, or MPC8255ACZUMHBB equivalent, key selection criteria include CPM-based HDLC/UART/ATM-IMA support, 60x bus interface timing at 266 MHz core/133 MHz CPM, 480-pin TBGA package thermal performance (θJA = 83°C/W on 4-layer board), and voltage compliance (VDD = 1.9–2.2 V, VDDH = 3.135–3.465 V).

Technical Context

The MPC8255ACZUMHBB integrates a PowerPC G2 core and an autonomous RISC-based CPM sharing 32 KB dual-port RAM. Core and CPM operate on independent PLLs-enabling asynchronous clocking (e.g., 266 MHz core / 133 MHz CPM)-and support bus snooping for cache coherency. Its memory controller provides glueless interfacing to SDRAM, SRAM, Flash, and EPROM with programmable bank sizing and byte-select control.

CPM functionality includes serial DMA per channel, virtual IDMA, parallel I/O with interrupt capability, and protocol-specific microcode engines for FCC (10/100-Mbps Ethernet via MII, HDLC up to T3), SCC (Ethernet, HDLC, UART, BISYNC), SMC (GCI/TDM management), and MCC2 (128-channel TDM multiplexing). The device implements four TDM interfaces (not eight like MPC8266) and excludes PCI bridge, 60x-to-PCI bridge, FCC3, MCC1, and TC-layer hardware.

Key Specifications

Pinout & Package

Package: 480-ball TBGA (19 mm × 19 mm, 1.27 mm pitch), RoHS-compliant, thermal resistance θJA = 83°C/W (4-layer board, natural convection).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC8260AZUUHBB and MPC8313EVRAGDB, the MPC8255ACZUMHBB delivers best-in-class CPM efficiency for 4-TDM, dual-FCC, quad-SCC telecom edge applications - offering proven microcode compatibility, lower thermal footprint (θJA = 83°C/W), and direct drop-in replacement for legacy MPC8250/MPC8260A designs without PCB changes.

Availability

MPC8255ACZUMHBB is available at Aetrix Electronics and suitable for telecom infrastructure, industrial gateways, and secure RTUs requiring stable component supply across extended product lifecycles and obsolescence-sensitive deployments.

Supply support for MPC8255ACZUMHBB 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 is a global semiconductor leader focused on automotive, industrial & IoT, mobile, and communication infrastructure solutions, with deep heritage in Power Architecture® processors.

The MPC8255ACZUMHBB belongs to the PowerQUICC™ II family, designed specifically for cost-sensitive, power-efficient communications equipment requiring hardware-accelerated protocol processing without full PCI complexity or modern security engines.

FAQ

What is the maximum operating frequency of the MPC8255ACZUMHBB core?

The MPC8255ACZUMHBB supports a maximum core frequency of 266 MHz, achievable at VDD = 1.9–2.2 V and ambient temperature ≤ 70°C. This frequency is validated per Table 5 in the MPC8260AEC Rev. 2.0 datasheet for the MPC8255 variant. Operation above 266 MHz is not supported; the device will throttle or fail to boot if configured beyond this limit. The MPC8255ACZUMHBB uses the same HiP4 silicon process as the MPC8260A, with frequency binning confirmed in Freescale's ordering information section.

Does the MPC8255ACZUMHBB include a PCI interface?

No, the MPC8255ACZUMHBB does not include a PCI interface. Per Figure 1 notes and Section 1 features of the MPC8260AEC Rev. 2.0 datasheet, PCI bridge functionality is explicitly excluded from the MPC8255 - it is only present on MPC8265 and MPC8266 variants. The MPC8255ACZUMHBB provides 60x and local buses only; any PCI connectivity must be added externally via a companion bridge IC. This omission reduces die size, power, and cost for applications that do not require PCI expansion.

How many TDM interfaces does the MPC8255ACZUMHBB support?

The MPC8255ACZUMHBB supports exactly four TDM interfaces, as confirmed in the "Notes" section of Figure 1 and Section 1 "Features" (page 5) of the MPC8260AEC Rev. 2.0 datasheet. This is half the eight TDM ports available on MPC8266. Each TDM interface supports bit- or byte-resolution time-slot assignment, 2048-byte SI RAM, and framing for T1/E1, ISDN, and Freescale IDL protocols - sufficient for mid-scale access concentrators and voice gateways.

What are the required supply voltages for the MPC8255ACZUMHBB?

The MPC8255ACZUMHBB requires three regulated supplies: VDD = 1.9–2.2 V (core/PLL), VDDH = 3.135–3.465 V (I/O), and VCCSYN = 1.9–2.2 V (PLL). Per Table 2 of the MPC8260AEC Rev. 2.0 datasheet, these rails must track within ±5% and ±0.1 Vdc during all operating conditions. Failure to meet tracking specs risks timing violations or latch-up. The MPC8255ACZUMHBB has no internal voltage regulators - external PMIC or discrete LDOs are mandatory.

Is the MPC8255ACZUMHBB pin-compatible with other PowerQUICC II processors?

The MPC8255ACZUMHBB is pin-compatible with the MPC8260A and MPC8264 in the 480-ball TBGA package (orderable part suffix MHBB), as confirmed by identical pinout diagrams in Section 4 of the MPC8260AEC Rev. 2.0 datasheet. However, functional differences exist: MPC8255ACZUMHBB lacks PCI bridge, FCC3, MCC1, and TC-layer hardware present on MPC8266. Pin compatibility enables PCB reuse, but firmware and microcode must be validated for the specific feature set of MPC8255ACZUMHBB.