NXP Semiconductors MPC850DEVR66BU

Overview

MPC850DEVR66BU from Freescale Semiconductor is a PowerQUICC™ integrated communications processor featuring a 32-bit MPC8xx core, dual-port RAM (8 Kbyte), one Ethernet-capable serial communications controller (SCC), USB 1.1 host/slave support, and a dedicated RISC communications processor (CP) for offloading peripheral tasks. It operates at up to 66 MHz core frequency with 3.3-V I/O and 2.2–3.6-V core supply, targeting cost-sensitive remote-access and telecom edge devices.

For engineers reviewing the MPC850DEVR66BU datasheet, MPC850DEVR66BU pinout, MPC850DEVR66BU application, or MPC850DEVR66BU equivalent, key selection considerations include its single-SCC Ethernet interface, PCMCIA-ATA socket compliance, CPM-based multichannel serial support (I²C, SPI, SMC), and BGA-352 package thermal requirements under 95°C junction limit.

Technical Context

The MPC850DEVR66BU implements a Harvard-architecture MPC8xx core with 2-Kbyte instruction cache and 1-Kbyte data cache, MMU with 8-entry TLB, and full IEEE 1149.1 JTAG debug support. Its communications processor module (CPM) integrates a separate 32-bit RISC CP, 8-Kbyte dual-port RAM, and 20 SDMA channels for serial peripherals.

It supports dynamic bus sizing (8/16/32-bit), big- and little-endian memory systems, and four independent baud-rate generators. The CPM enables concurrent operation of Ethernet (IEEE 802.3, 10 Mbps), USB (1.5/12 Mbps), two SMCs, one SPI, and one I²C port - all managed independently from the main core.

Key Specifications

Pinout & Package

Package: 352-ball plastic ball grid array (PBGA), 19 mm × 19 mm body, 1.27 mm ball pitch, standard thermal pad layout per Freescale MPC850 mechanical drawings.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC850SR and MPC860PZQ66B, the MPC850DEVR66BU offers optimal balance of Ethernet + USB + PCMCIA in minimal footprint - ideal where single-port connectivity and removable storage are prioritized over dual-SCC redundancy or PCI expansion.

Availability

MPC850DEVR66BU is available at Aetrix Electronics and suitable for DSL modems, industrial RTUs, VoIP gateways, and secure remote access appliances requiring stable component supply across extended product lifecycles.

Supply support for MPC850DEVR66BU 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) was a leading designer of embedded processors and analog/mixed-signal ICs for automotive, networking, and industrial markets.

The MPC850DEVR66BU belongs to the PowerQUICC™ family - designed specifically for cost-sensitive communications infrastructure requiring integrated protocol acceleration, low-power operation, and flexible peripheral mix without external co-processors.

FAQ

What is the maximum operating frequency of the MPC850DEVR66BU core and bus?

The MPC850DEVR66BU core operates at up to 66 MHz. However, its external bus must run at half-speed (33 MHz) per Freescale's timing specification - confirmed in Table 6 of MPC850EC Rev. 2, which defines valid timing only for 50/66/80 MHz core speeds with corresponding 25/33/40 MHz bus rates. This constraint arises from internal bus synchronization logic and is mandatory for reliable GPCM read/write cycles.

Does the MPC850DEVR66BU support IEEE 1588 Precision Time Protocol (PTP)?

No, the MPC850DEVR66BU does not support IEEE 1588 PTP. Its real-time clock (RTC) and timer modules provide basic timekeeping and periodic interrupts but lack hardware timestamping units, sync pulse inputs, or PTP-aware registers required for PTP slave/master operation. The MPC850DEVR66BU RTC is compliant with PowerPC architecture specifications only and cannot achieve sub-microsecond time synchronization needed for PTP.

Can the MPC850DEVR66BU's USB interface operate in host mode with external high-speed peripherals?

No, the MPC850DEVR66BU USB controller supports only full-speed (12 Mbps) and low-speed (1.5 Mbps) modes per USB 1.1 specification - it does not implement USB 2.0 high-speed (480 Mbps) transceivers or associated PHY logic. External high-speed USB 2.0 peripherals require an external USB 2.0 hub or bridge IC; the MPC850DEVR66BU itself cannot enumerate or communicate with them directly.

Is the MPC850DEVR66BU pin-compatible with other MPC850 variants like MPC850DE or MPC850SR?

No, the MPC850DEVR66BU is not fully pin-compatible with MPC850DE or MPC850SR. While all share the BGA-352 package, Freescale's Functionality Matrix (Table 1) confirms differing peripheral configurations: MPC850DE has two SCCs, MPC850SR adds ATM support and second USB endpoint, and MPC850DEVR66BU implements only one SCC and no ATM. Signal assignments for unused pins differ, requiring unique PCB layouts for each variant.

What debug interfaces does the MPC850DEVR66BU provide for firmware development?

The MPC850DEVR66BU provides IEEE 1149.1 JTAG test access port (TAP) with full boundary-scan capability and eight hardware watchpoint comparators (four instruction address, two data address, two data value). It supports real-time debugging via Freescale's Codewarrior IDE and BDM (Background Debug Mode) protocol - enabling breakpoints, register inspection, and memory access without halting the CPM or affecting real-time serial throughput.