NXP Semiconductors MPC852TZT80A

Overview

MPC852TZT80A from Freescale Semiconductor is a PowerPC architecture-based integrated communications controller featuring an MPC8xx core operating up to 80 MHz, 66-MHz external bus, 1.8-V core/3.3-V I/O with 5-V TTL compatibility, and integrated Fast Ethernet Controller (FEC), CPM, and memory controller. It serves as a single-chip solution for embedded networking control in CPE equipment, VoIP clients, and WiFi access points.

For engineers reviewing the MPC852TZT80A datasheet, MPC852TZT80A pinout, MPC852TZT80A application, or MPC852TZT80A equivalent, key selection criteria include confirmed 80 MHz core frequency in 2:1 bus mode, FEC compliance with IEEE 802.3 at 10 Mbps, dual-port RAM size, cache coherency implementation, and mandatory reset configuration register values per HRCW and SIUMCR.

Technical Context

The MPC852TZT80A implements a single-issue 32-bit MPC8xx core with 4-Kbyte instruction and data caches (two-way set-associative, 128 sets each), MMU with 32-entry fully associative TLBs supporting 4/16/512 KB and 8 MB page sizes, and lockable cache blocks. Its system integration unit includes JTAG debug interface, software watchdog, PIT, and clock synthesizer.

Communication subsystem comprises a RISC-based CPM with 8-Kbyte dual-port RAM, eight SDMA channels, two SCCs supporting HDLC/UART/Ethernet (SCC3/SCC4), one SMC, one SPI, and PCMCIA-ATA interface compliant with Release 2.1. The FEC supports MII interface and full 10-Mbps IEEE 802.3 operation.

Key Specifications

Pinout & Package

The MPC852TZT80A is housed in a 272-ball PBGA package (package code ZT) with 1.27 mm ball pitch, thermally enhanced construction, and exposed thermal pad. Pin assignment follows Freescale's standard MPC852T layout with dedicated VDD/VSS groups per functional block (core, I/O, PLL, FEC).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC852TZT80A, MPC866PZQ80B provides higher-speed Ethernet and USB but increases BOM cost and layout complexity, while MPC855TZQ80C adds PCI and RAM at the expense of thermal margin-both require revalidation of reset configuration and power sequencing.

Availability

MPC852TZT80A is available at Aetrix Electronics and suitable for DSL gateways, VoIP terminal adapters, WiFi access points, and industrial Ethernet bridges requiring stable component supply across extended temperature ranges (–40°C to +100°C junction).

Supply support for MPC852TZT80A 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 fabless semiconductor company specializing in embedded processors, analog, and connectivity solutions for automotive, industrial, and networking markets.

The MPC852TZT80A belongs to the PowerQUICC™ family of integrated communications controllers designed specifically for cost-sensitive, low-power embedded networking applications where single-chip integration of CPU, FEC, CPM, and memory controller reduces system-level component count.

FAQ

What is the maximum supported core frequency for MPC852TZT80A and what bus mode is required?

The MPC852TZT80A supports a maximum core frequency of 80 MHz, which requires operation in 2:1 bus mode with a 40 MHz external bus clock. This is explicitly defined in the MPC852T Hardware Specifications Rev. 4, Section 2 Features, where 80/100 MHz core frequencies are stated to support 2:1 mode only. Attempting 80 MHz operation in 1:1 mode violates timing specifications and may cause undefined behavior or failure to boot.

Does MPC852TZT80A support 100-Mbps Fast Ethernet operation?

No, the MPC852TZT80A FEC supports only 10-Mbps IEEE 802.3 Ethernet operation, as confirmed in Section 2 Features stating "Ethernet/IEEE 802.3® standard optional on SCC3 and SCC4, supporting full 10-Mbps operation." It lacks the physical layer signaling and timing circuitry required for 100-Mbps MII operation, unlike later derivatives such as MPC866P.

What are the mandatory reset configuration register settings required after HRESET deassertion for MPC852TZT80A?

After HRESET deassertion, MPC852TZT80A requires programming SIUMCR[DBGC] to binary X1 and configuring MBMR[GPLB4DIS] = 0, PAPAR/PADIR, PBPAR/PBDIR, and PCPAR/PCDIR fields per Table 6 in the Hardware Specifications. These settings are mandatory for correct GPIO initialization and debug controller operation, and failure to apply them results in undefined port behavior or inability to enter debug mode.

How does the 5-V tolerance work on MPC852TZT80A I/O pins, and which pins are covered?

MPC852TZT80A has 5-V tolerant pins including PA[0:3], PA[8:11], PB15, PB[24:25], PB[28:31], PC[4:7], PC[12:13], PC15, PD[3:15], and all JTAG/MII signals (TDI, TDO, TCK, TRST, TMS, MII_TXEN, MII_MDIO). Per Section 6 DC Characteristics, these pins tolerate up to 5.5 V but must not exceed VDDH by more than 2.5 V-so with VDDH = 3.465 V, absolute max is 5.965 V, though 5.5 V is the rated limit.

What thermal resistance values apply to MPC852TZT80A in a four-layer PCB design with 200 ft/min airflow?

In a four-layer board (2s2p) with 200 ft/min airflow, MPC852TZT80A exhibits RθJMA = 29°C/W (junction-to-ambient), RθJB = 24°C/W (junction-to-board), and ΨJT = 2°C/W (junction-to-package top). These values are specified in Table 3 of the Hardware Specifications and are critical for calculating junction temperature using TJ = TA + (RθJA × PD) or TJ = TB + (RθJB × PD) depending on whether ambient or board temperature is known.