The following are portions of a recent NASA press release:

PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011

Mars Polar Lander Mission Status

January 3, 1999

"Mars Polar Lander -- due to become the first spacecraft to set down near the edge of Mars' southern polar cap -- pierced through a blustery, cloud-covered Florida sky at 3:21 p.m. Eastern Standard Time today atop a Delta II launch vehicle from Cape Canaveral Air Station's Launch Complex 17B. The spacecraft, launched successfully on the first day of the launch period, is equipped with a robotic arm to dig beneath the layered terrain of the Martian polar region and two microprobes to crash into the planet's surface and conduct two days of soil and water experiments up to 1 meter (3 feet) below the Martian surface."

"Mars Polar Lander is the second of two spacecraft launched to the red planet during the December 1998-January 1999 Mars launch opportunity. Mars Climate Orbiter was launched December 11, and is scheduled to reach Mars next September 23. Onboard Mars Polar Lander are two microprobes developed as the Deep Space 2 project under NASA's New Millennium Program. The Deep Space 2 probes will smash into the Martian surface as a test of new technologies for future planetary descent probes."

TAG was responsible for the design of a CMOS mixed signal integrated circuit which is carried by each of the two microprobes as well as a companion thin film resistor chip. Each CMOS monolithic integrated circuit contains analog multiplexers, references and regulators, an analog-to-digital converter and eight 10-bit digital-to-analog converters. The devices also carry microprocessor interface electronics and power management circuits. The circuits must operate at an ambient temperature of approximately -120C and consume minimum power to prolong the life expectancy of the battery powered experiment.

Further information can be obtained from the JPL/NASA web site: http://www.jpl.nasa.gov.

The the two Deep Space 2 vehicles will free fall into Mars. During decent they will measure barometric pressure, temperature and deceleration. At impact they will measure deceleration and impact-shock. Measurements will continue as long as battery power lasts. The TAG designed integrated circuit contains a forty eight channel analog multiplexer. Thirty five channels (two banks of sixteen plus three spares) are available for system use. The remaining channels are used to monitor the output of eight 10-bit digital-to-analog converters on the chip as well as internal reference voltages and a thermometer circuit. Selected user channels are routed to an analog-to-digital converter on the chip. Input/output data are passed to a companion microprocessor over a 12-bit digital bus.

When the microprobes impact Mars at a speed of approximately 400 MPH, the aft body remains at the surface and the fore body penetrates into the Martian soil for as much as a meter or more. A cable is played out between the fore body and the aft body which contains a radio transceiver as well as other scientific experiments. Data are transmitted to the orbiting vehicle to be relayed to earth.

The microcontroller project involved major contributions from several contractors including Mission Research Corporation, Boeing and GE -- to name just a few. Many more companies were involved in the overall microprobe project.




The level of integration in the project is illustrated in the image of the micro-controller board at the right which contains a microprocessor, Non-volatile Read/Write Memory, Random Access Memory, clock and power electronics. The only features that are visible in the image are power supply bypass capacitors and electrical connections at the edge of the board. The TAG chip, microprocessor, memory devices, etc. are buried in the multi-chip-module assembly (green board).

Artwork for this web page has been obtained from the NASA project site. The content of this page is for information only is not meant to imply NASA endorsement of TAG or any of the other participants in the project.



The following are portions of a recent TRW press release:

Tuesday August 18, 10:30 am Eastern Time

Company Press Release

TRW Delivers Initial F-22 Avionics System

"SAN DIEGO--(BUSINESS WIRE)--Aug. 18, 1998--TRW has reached an important milestone by successfully delivering a communications, navigation and identification (CNI) avionics system to the Air Force to be used on the F-22 fighter jet, which began the flight test phase of the program in 1997."

"This unique design approach uses integrated electronics, with multiple processing and radio functions performed by a robust, wideband set of general purpose electronics. The system is capable of reconfiguring its components to counteract faults and failures -- even those caused by battle damage -- enabling pilots to
continue their mission and return safely."

TAG participated with LSI Logic in the development of a VLSI CMOS mixed signal integrated circuit used in this program. The TAG design includes an analog multiplexer and analog-to-digital converter that is used in the health monitoring subsystem.