Features
• 3000 Dhrystone 2.1 MIPS at 1.3 GHz
• Selectable Bus Clock (30 CPU Bus Dividers up to 28x)
• 13 Selectable Core-to-L3 Frequency Divisors
• Selectable MPx/60x Interface Voltage (1.8V, 2.5V)
• Selectable L3 Interface of 1.8V or 2.5V
• PD Typical 12.6W at 1 GHz at VDD = 1.3V; 8.3W at 1 GHz at VDD = 1.1V, Full Operating
Conditions
• Nap, Doze and Sleep Modes for Power Saving
• Superscalar (Four Instructions Fetched Per Clock Cycle)
• 4 GB Direct Addressing Range
PowerPC®
7447/7457
• Virtual Memory: 4 Hexabytes (252)
• 64-bit Data and 36-bit Address Bus Interface
• Integrated L1: 36 KB Instruction and 32 KB Data Cache
• Integrated L2: 512 KB
• 11 Independent Execution Units and Three Register Files
• Write-back and Write-through Operations
• fINT Max = 1 GHz (1.2 GHz to be Confirmed)
• fBUS Max = 133 MHz/166 MHz
PC7447/57
Preliminary
Description
This document is primarily concerned with the PowerPC PC7457; however, unless
otherwise noted, all information here also applies to the PC7447. The PC7457 and
PC7447 are implementations of the PowerPC microprocessor family of reduced
instruction set computer (RISC) microprocessors. This document describes pertinent
electrical and physical characteristics of the PC7457.
The PC7457 is the fourth implementation of the fourth generation (G4) microproces-
sors from Freescale. The PC7457 implements the full PowerPC 32-bit architecture
and is targeted at networking and computing systems applications. The PC7457 con-
sists of a processor core, a 512 Kbyte L2, and an internal L3 tag and controller which
support a glueless backside L3 cache through a dedicated high-bandwidth interface.
The PC7447 is identical to the PC7457 except it does not support the L3 cache
interface.
The core is a high-performance superscalar design supporting a double-precision
floating-point unit and a SIMD multimedia unit. The memory storage subsystem sup-
ports the MPX bus interface to main memory and other system resources. The L3
interface supports 1, 2, or 4M bytes of external SRAM for L3 cache and/or private
memory data. For systems implementing 4M bytes of SRAM, a maximum of 2M bytes
may be used as cache; the remaining 2M bytes must be private memory.
Note that the PC7457 is a footprint-compatible, drop-in replacement in a PC7455
application if the core power supply is 1.3V.
Rev. 5345C–HIREL–07/05