NXP Semiconductors MPC857TZQ100B

Overview

MPC857TZQ100B from Freescale Semiconductor is a PowerQUICC™ family integrated communications processor combining a 32-bit MPC8xx PowerPC core, Communications Processor Module (CPM), and System Integration Unit (SIU) in a single PBGA package. It delivers 100 MHz CPU operation, 4 KB instruction/4 KB data cache, single Fast Ethernet controller (FEC) with MII support, one SCC (SCC1) for Ethernet/ATM, and one SMC (SMC1) for UART - targeting DSL access multiplexers and ATM edge devices.

For engineers reviewing the MPC857TZQ100B datasheet, MPC857TZQ100B pinout, MPC857TZQ100B application, or MPC857TZQ100B equivalent, this page provides verified functional identity, confirmed thermal/power specs at 100 MHz, validated package mapping to 357-pin PBGA, real-world timing constraints for bus and FEC interfaces, and two documented alternative parts with precise technical and application-level distinctions.

Technical Context

The MPC857TZQ100B implements a single-issue 32-bit PowerPC architecture core with MMU (32-entry ITLB/DTLB), branch prediction, and physically addressed caches. Its CPM executes serial protocols independently via 10 SDMA channels and dual-port RAM, while the SIU integrates memory controller (8 banks), 4 timers, IEEE 1149.1 JTAG, and clock synthesizer.

It supports enhanced SAR (ESAR) mode for ATM OAM/PM, UTOPIA Level 2 (half-duplex), simultaneous MII and UTOPIA operation, and AAL2/VBR functionality stored in ROM. Unlike MPC862 variants, it omits TSA, second SMC, and multi-SCC support - confirming its targeted role in cost-optimized DSL termination equipment.

Key Specifications

Pinout & Package

Package: 357-pin plastic ball grid array (PBGA), RoHS-compliant, 27 mm × 27 mm footprint, 1.27 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPC857TZQ100B, MPC857TZQ100B has identical silicon and qualification - the 'Z' prefix reflects Freescale's internal traceability coding. Against MPC857DSLZQ100B, MPC857TZQ100B trades multi-PHY UTOPIA for integrated MII Ethernet, making it superior for hybrid DSL/management platforms requiring both ATM data plane and IP control plane.

Availability

MPC857TZQ100B is available at Aetrix Electronics and suitable for DSL access multiplexers, ATM edge concentrators, residential gateway controllers, and industrial protocol converters requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MPC857TZQ100B 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 MPC857TZQ100B belongs to the PowerQUICC™ family - engineered specifically for cost-sensitive, high-reliability communications infrastructure where integrated ATM, Ethernet, and serial protocol acceleration reduce system-level complexity.

FAQ

What is the maximum operating frequency of the MPC857TZQ100B?

The MPC857TZQ100B is rated for 100 MHz CPU operation in 2:1 bus mode (CPU clock twice the bus clock). At this frequency, it delivers 1.35 W typical power dissipation and requires junction temperature monitoring to stay within the 115 °C extended limit. The device must be configured for half-speed bus timing (e.g., 50 MHz bus) when running at 100 MHz CPU - confirmed in Section 9 of the MPC862/857T/857DSL Hardware Specifications Rev. 3. This timing constraint directly impacts memory controller setup and peripheral interface synchronization in MPC857TZQ100B designs.

Does the MPC857TZQ100B support IEEE 1149.1 JTAG debugging?

Yes, the MPC857TZQ100B includes full IEEE 1149.1 test access port (TAP) support as part of its System Integration Unit (SIU), enabling boundary-scan testing, real-time core debugging, and CPM register inspection. Pins TMS, TCK, TDI, TDO, and TRST are dedicated to JTAG functionality and operate at 3.3 V logic levels. This capability is documented in Section 10 of the MPC862/857T/857DSL Hardware Specifications Rev. 3 and is functionally identical across all members of the MPC862/857T/857DSL family, including MPC857TZQ100B.

What type of cache does the MPC857TZQ100B implement?

The MPC857TZQ100B implements a 4 KB two-way set-associative instruction cache and a 4 KB two-way set-associative data cache, both physically addressed with LRU replacement and lockable on a 4-word (128-bit) block basis. Cache coherency is maintained automatically for both instruction and data paths. These values are explicitly defined in Table 1 and Section 2 of the MPC862/857T/857DSL Hardware Specifications Rev. 3 and distinguish MPC857TZQ100B from the MPC862P (16 KB/8 KB caches) and MPC862T (4 KB/4 KB, same as MPC857TZQ100B).

Can the MPC857TZQ100B support multiple Ethernet PHYs simultaneously?

No, the MPC857TZQ100B supports only one Fast Ethernet controller (FEC) with MII interface - limiting it to a single 10/100Base-T PHY connection. It does not provide UTOPIA Level 2 multi-PHY capability like the MPC857DSL variant. Section 1 of the MPC862/857T/857DSL Hardware Specifications Rev. 3 confirms MPC857TZQ100B has "1" Ethernet instance, and Figure 2 shows no UTOPIA PHY multiplexing logic. For multi-PHY ATM aggregation, MPC857DSLZQ100B is the appropriate variant - not MPC857TZQ100B.

What is the thermal resistance (RθJA) for the MPC857TZQ100B in natural convection?

The MPC857TZQ100B has a junction-to-ambient thermal resistance (RθJA) of 37 °C/W under natural convection on a single-layer board (1s), as specified in Table 3 of the MPC862/857T/857DSL Hardware Specifications Rev. 3. With 1.54 W maximum power dissipation at 100 MHz, this yields a theoretical junction-to-ambient delta of 57 °C - meaning ambient must remain below 58 °C to meet the 115 °C junction limit. This value assumes standard JEDEC JESD51-2 test conditions and is critical for heatsink selection in MPC857TZQ100B-based DSLAM designs.