NXP Semiconductors XPC850SRZT50BU

Overview

XPC850SRZT50BU from Freescale Semiconductor is a PowerQUICC™ integrated communications processor featuring a 32-bit MPC8xx core, dual-port RAM (8 KB), two serial communications controllers (SCCs) with Ethernet/IEEE 802.3 support, USB 1.1 host/slave controller, and CPM-based offload architecture - designed for remote-access gateways, DSL/CPE edge devices, and cost-sensitive telecom infrastructure.

For engineers reviewing the XPC850SRZT50BU datasheet, XPC850SRZT50BU pinout, XPC850SRZT50BU application, or XPC850SRZT50BU equivalent, key selection criteria include its 50 MHz core frequency, 3.3 V operation with 5 V-tolerant I/O, BGA-352 package, IEEE 1149.1 JTAG debug interface, and dual SCC support for concurrent Ethernet + ATM/HDLC protocols.

Technical Context

The XPC850SRZT50BU implements a Harvard-architecture 32-bit MPC8xx core with 2 KB instruction cache and 1 KB data cache, MMU with 8-entry TLB, and branch prediction without conditional execution. Its Communications Processor Module (CPM) contains a dedicated 32-bit RISC CP, 8 KB dual-port RAM, and 20 SDMA channels - enabling concurrent protocol handling across SCCs, SMCs, USB, and SPI without CPU intervention.

It supports full 10 Mbps Ethernet (IEEE 802.3), ATM (MPC850SR variant), HDLC/SDLC up to 2 Mbps per channel, USB 1.1 at 1.5/12 Mbps, and TDM time-slot assignment for ISDN/T1/CEPT interfaces. The CPM executes microcode-driven protocol engines including GRACEFUL STOP TRANSMIT and CLOSE RXBD for deterministic frame control.

Key Specifications

Pinout & Package

Package: 352-ball plastic ball grid array (PBGA), 27 mm × 27 mm, 1.27 mm pitch, RoHS-compliant. Thermal pad center (ball A17–Q17) must be soldered to internal ground plane for θJC = 8 °C/W performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC850DEZT50B and MPC850DSLZT50B, the XPC850SRZT50BU uniquely retains both ATM capability and full USB 1.1 host/slave functionality - making it the only MPC850 variant suitable for hybrid DSL/CPE designs requiring simultaneous broadband backhaul and local USB peripheral support.

Availability

XPC850SRZT50BU is available at Aetrix Electronics and suitable for DSL access concentrators, remote terminal units, VoIP gateways, and industrial protocol converters requiring stable component supply across extended product lifecycles.

Supply support for XPC850SRZT50BU 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) pioneered PowerQUICC™ communications processors for embedded networking, emphasizing integration, power efficiency, and protocol offload.

The MPC850 family was designed specifically for cost-sensitive telecommunications infrastructure - integrating CPU, memory controller, CPM, and multiple serial interfaces into a single BGA package to replace multi-chip controller solutions in CPE and edge equipment.

FAQ

What is the maximum operating frequency of the XPC850SRZT50BU core?

The XPC850SRZT50BU operates at a maximum core frequency of 50 MHz, as confirmed by Freescale's MPC850EC Rev. 2 specification and validated in Table 4 (Power Dissipation) for 50 MHz operation. This frequency is fixed by the part's speed grade and cannot be overclocked; higher-speed variants like MPC850SRZT66B exist but are distinct orderables.

Does the XPC850SRZT50BU support IEEE 1149.1 JTAG debugging?

Yes, the XPC850SRZT50BU includes full IEEE 1149.1 JTAG test access port (TAP) with TMS, TCK, TDI, TDO, and TRST pins. It supports boundary-scan testing, flash programming, and real-time debugging via standard in-circuit emulators - documented in Section 7 of the MPC850EC Rev. 2 hardware spec.

What package type and pin count does the XPC850SRZT50BU use?

The XPC850SRZT50BU uses a 352-ball plastic BGA (PBGA) package with 27 mm × 27 mm footprint and 1.27 mm ball pitch. Mechanical data is specified in Section 9 of the MPC850EC Rev. 2 document, including solder mask clearance, thermal pad requirements, and land pattern recommendations.

Can the XPC850SRZT50BU operate with 5 V-tolerant I/O pins?

Yes, all general-purpose I/O and peripheral pins on the XPC850SRZT50BU tolerate input voltages up to 5.5 V (VIH = 2.0–5.5 V), as stated in Table 5 of the MPC850EC Rev. 2 spec. However, absolute maximum ratings require that input voltage never exceed VDDH + 2.5 V - so 3.3 V supply mandates ≤5.8 V input.

What serial communication protocols does the XPC850SRZT50BU support natively?

The XPC850SRZT50BU natively supports Ethernet (IEEE 802.3, 10 Mbps), ATM (UTOPIA Level 1), HDLC/SDLC (up to 2 Mbps), USB 1.1 (1.5/12 Mbps), UART, SPI, I²C, and TDM-based protocols (ISDN, T1, CEPT) - all implemented in hardware via its CPM and SCC/SMC peripherals without CPU overhead.