PA-7200
Encyclopedia
The PA-7200 code-named Thunderbird' , is a microprocessor
that implements the PA-RISC 1.1
instruction set architecture (ISA) developed by Hewlett-Packard
(HP). It was introduced in early 1995, debuting in systems from HP. The PA-7200 was not sold openly and the only third-party users were Convex Computer
and Stratus Computer, both members of the Precision RISC Organization (PRO). It was developed for small multiprocessing
systems with two or four microprocessors. The microprocessor was first described at the Compcon and IEEE International Solid-State Circuits Conference
(ISSCC) conferences.
and was improved adding a second integer unit, enabling it to issue up to two integer instructions per cycle. The second integer unit was not identical to the first, and only was only capable of executing simple but more frequently used instructions.
The PA-7200 contained 1.3 million transistor
s and measured 14.0 mm by 15.0 mm (210 mm2). It was fabricated by Hewlett-Packard in their CMOS14A process which they co-developed with Analog Devices
. CMOS14A was a 0.55 µm, three-level interconnect, complementary metal–oxide–semiconductor (CMOS) process.
The microprocessor uses an unusual 4.4 V power supply as a result of its development. It was designed in the 0.8 µm CMOS26B process and leveraged circuits and layouts from the PA-7100, which was also designed for CMOS26B. The completed design was then shrunk for the 0.55 µm CMOS14A process. This process has 120-angstrom
gate oxide that did not tolerate 5.0 V operation. A 3.3 V power supply did not enable the microprocessor to achieve the intended clock frequency, so 4.4 V was chosen as a compromise.
Microprocessor
A microprocessor incorporates the functions of a computer's central processing unit on a single integrated circuit, or at most a few integrated circuits. It is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and...
that implements the PA-RISC 1.1
PA-RISC
PA-RISC is an instruction set architecture developed by Hewlett-Packard. As the name implies, it is a reduced instruction set computer architecture, where the PA stands for Precision Architecture...
instruction set architecture (ISA) developed by Hewlett-Packard
Hewlett-Packard
Hewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...
(HP). It was introduced in early 1995, debuting in systems from HP. The PA-7200 was not sold openly and the only third-party users were Convex Computer
Convex Computer
Convex Computer Corporation was a company that developed, manufactured and marketed vector minisupercomputers and supercomputers for small-to-medium-sized businesses. Their later Exemplar series of parallel computing machines were based on the Hewlett-Packard PA-RISC microprocessors, and in 1995,...
and Stratus Computer, both members of the Precision RISC Organization (PRO). It was developed for small multiprocessing
Multiprocessing
Multiprocessing is the use of two or more central processing units within a single computer system. The term also refers to the ability of a system to support more than one processor and/or the ability to allocate tasks between them...
systems with two or four microprocessors. The microprocessor was first described at the Compcon and IEEE International Solid-State Circuits Conference
International Solid-State Circuits Conference
International Solid-State Circuits Conference is a global forum for presentation of advances in solid-state circuits and Systems-on-a-Chip. The Conference offers a unique opportunity for engineers working at the cutting edge of IC design to maintain technical currency, and to network with leading...
(ISSCC) conferences.
Description
The PA-7200 was mostly derived from the PA-7100PA-7100
The PA-7100 is a microprocessor developed by Hewlett-Packard that implemented the PA-RISC 1.1 instruction set architecture . It is also known as the PCX-T and by its code-name Thunderbird. It was introduced in early 1992 and was the first PA-RISC microprocessor to integrate the floating-point unit...
and was improved adding a second integer unit, enabling it to issue up to two integer instructions per cycle. The second integer unit was not identical to the first, and only was only capable of executing simple but more frequently used instructions.
The PA-7200 contained 1.3 million transistor
Transistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
s and measured 14.0 mm by 15.0 mm (210 mm2). It was fabricated by Hewlett-Packard in their CMOS14A process which they co-developed with Analog Devices
Analog Devices
Analog Devices, Inc. , known as ADI, is an American multinational semiconductor company specializing in data conversion and signal conditioning technology, headquartered in Norwood, Massachusetts...
. CMOS14A was a 0.55 µm, three-level interconnect, complementary metal–oxide–semiconductor (CMOS) process.
The microprocessor uses an unusual 4.4 V power supply as a result of its development. It was designed in the 0.8 µm CMOS26B process and leveraged circuits and layouts from the PA-7100, which was also designed for CMOS26B. The completed design was then shrunk for the 0.55 µm CMOS14A process. This process has 120-angstrom
Ångström
The angstrom or ångström, is a unit of length equal to 1/10,000,000,000 of a meter . Its symbol is the Swedish letter Å....
gate oxide that did not tolerate 5.0 V operation. A 3.3 V power supply did not enable the microprocessor to achieve the intended clock frequency, so 4.4 V was chosen as a compromise.
Further reading
- Rashid, E.; et al. (1994). "A CMOS RISC CPU with on-chip parallel cache". ISSCC Digest of Technical Papers.