NXP Semiconductors XPC850DSLCZT50BU

Overview

XPC850DSLCZT50BU from Freescale Semiconductor is a PowerQUICC™ integrated communications processor combining an embedded 32-bit MPC8xx core with a dedicated RISC communications processor (CP), dual-port RAM (8 KB), two SCCs supporting Ethernet/HDLC, USB 1.1 host/slave, I²C, SPI, and PCMCIA-ATA interface - designed for DSL access multiplexers and remote telecom gateways operating at 50 MHz.

For engineers reviewing the XPC850DSLCZT50BU datasheet, XPC850DSLCZT50BU pinout, XPC850DSLCZT50BU application, or XPC850DSLCZT50BU equivalent, key selection criteria include its dual-SCC Ethernet/ATM support, 8-KB dual-port RAM allocation for CPM offload, 3.3-V I/O with 5-V tolerance, BGA-352 package thermal resistance (θ_JA = 31°C/W), and IEEE 1149.1 JTAG debug compliance.

Technical Context

The XPC850DSLCZT50BU implements a Harvard-architecture MPC8xx core (2-KB instruction cache, 1-KB data cache) coupled with a separate 32-bit RISC communications processor (CP) executing protocol-specific microcode for serial channel management. Its CPM handles up to seven serial interfaces - including two SCCs, one USB, two SMCs, one I²C, and one SPI - freeing the main core from real-time protocol processing.

It supports dynamic voltage scaling (2.2 V at ≤25 MHz, 3.3 V at 50 MHz), four independent baud-rate generators, time-slot assigner for TDM multiplexing, and low-power modes (Doze, Sleep, Deep Sleep). The memory controller supports DRAM, SDRAM, SRAM, and flash across eight banks with programmable block sizes (32 KB–256 MB) and boot-selectable bus width (8/16/32-bit).

Key Specifications

Pinout & Package

Package: 352-ball plastic ball grid array (PBGA), 27 mm × 27 mm, 1.27-mm pitch, RoHS-compliant. Thermal pad on underside requires solder paste stencil opening per Freescale AN-1231/D guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC850SRZT50B and MPC850DEZT50B, the XPC850DSLCZT50BU uniquely combines DSL-specific ATM support with USB 1.1 and PCMCIA-ATA - making it the only variant qualified for carrier-grade DSLAM line cards requiring both broadband access aggregation and local service provisioning.

Availability

XPC850DSLCZT50BU is available at Aetrix Electronics and suitable for DSL access multiplexers, remote telecom gateways, industrial protocol gateways, and legacy network bridges requiring stable component supply across extended product lifecycles.

Supply support for XPC850DSLCZT50BU 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™ architecture for embedded communications, delivering high-integration, low-power processors for networking and telecom infrastructure.

The MPC850 family was designed specifically for cost-sensitive, remote-access, and telecommunications applications - integrating Ethernet, ATM, USB, and PCMCIA into a single chip to replace multi-chip controller solutions in DSLAMs and gateways.

FAQ

What is the maximum supported bus speed for the XPC850DSLCZT50BU?

The XPC850DSLCZT50BU supports a maximum bus speed of 50 MHz. Higher-frequency operation (e.g., 66 MHz or 80 MHz) requires half-speed bus mode configuration - meaning a 66-MHz part must be run with a 33-MHz bus clock. This limitation is enforced by internal timing margins and verified in Table 6 of the hardware specifications document.

Does the XPC850DSLCZT50BU support IEEE 1149.1 JTAG debugging?

Yes, the XPC850DSLCZT50BU includes full IEEE 1149.1 test access port (TAP) support with dedicated TMS, TCK, TDI, TDO, and TRST pins. It enables boundary-scan testing, in-circuit emulation, and real-time watchpoint debugging using eight configurable comparators for instruction/data address and value monitoring.

How much dual-port RAM is allocated to the communications processor in the XPC850DSLCZT50BU?

The XPC850DSLCZT50BU integrates 8 Kbytes of on-chip dual-port RAM shared between the MPC8xx core and the communications processor (CP). This RAM is used exclusively by the CPM for protocol descriptor tables, receive/transmit buffers, and microcode execution - enabling zero-copy data movement and deterministic latency for serial channel operations.

What power supply voltages does the XPC850DSLCZT50BU require at 50 MHz operation?

At 50 MHz operation, the XPC850DSLCZT50BU requires VDDH, VDDL, KAPWR, and VDDSYN supply voltages within 3.135 V to 3.465 V. All four supplies must be regulated to this range simultaneously; deviation outside these limits risks timing violation or functional failure per Table 5 DC electrical specifications.

Is the XPC850DSLCZT50BU pin-compatible with other MPC850 family members?

The XPC850DSLCZT50BU uses the standard MPC850 BGA-352 pinout defined in Freescale's mechanical data documentation. It shares identical pin assignments with MPC850SRZT50B and MPC850DEZT50B for power, clock, reset, JTAG, and memory interface signals - though peripheral pin functions (e.g., UTOPIA vs. DSL-specific ATM signals) differ per variant.