1. 12004 MAPLD: 141Buchner Single Event Effects Testing of the Atmel IEEE1355 Protocol Chip Stephen Buchner 1, Mark Walter 2, Moses McCall 3 and Christian Poivey 4 1 QSS Group Inc., Lanham MD 20772 2 Orbital Science Corp, Dulles VA 99999 3 NASA-GSFC, Greenbelt MD 20771 4 SGT-Inc, Greenbelt MD 20771

2. 22004 MAPLD: 141Buchner What is IEEE 1355? IEEE 1355 specifies the physical media and low level protocols for a family of serial interconnect systems. The speeds and media range from 10 Mbps to 1Gbps in both copper and optical technologies and are scalable. Data are transmitted between nodes via packets. Each packet consists of a header, a data section, and a CRC section (to flag errors). The header contains information concerning the destination node, data format, packet length, etc. The protocol is based on the “Seven-Layer Open System Interconnect Model”. Routers determine paths taken by packets through the internet.

3. 32004 MAPLD: 141Buchner IEEE 1355 Used in Solar Dynamic Observatory (SDO) Atmel ASICS located on NIC cards

4. 42004 MAPLD: 141Buchner Implementation Transmission protocols are controlled by an ASIC manufactured by Atmel. The ASIC is implemented in a 0.6  m three-level metal CMOS “Sea of Gates” technology (MG1RT). The ASIC contains logic elements, registers, memory and a phase lock loop. The device is a TSS901E Atmel chip capable of running three channels. It is mounted on a 4LINKS board that can be plugged into a computer slot.

5. 52004 MAPLD: 141Buchner Radiation Effects Ionizing particles in space produce both total ionizing dose (TID) degradation and single event effects (SEEs) in electronic circuits. TID causes a gradual degradation in performance manifested through increased leakage currents, slower operation and eventually functional failure. SEEs can take many forms. We are concerned with single event latchup (SEL) and single event upset (SEU). SEL may lead to destructive failure and SEU may halt operation. The SEU is then termed a single event functional interrupt (SEFI).

6. 62004 MAPLD: 141Buchner Previous Radiation Testing of Atmel Chip No parametric degradation up to a TID level of 40 Krad(Si). SEL threshold exceeds 120 MeV.cm 2 /mg. SEU testing of individual latches and memories only. Revealed a relatively low threshold that depended on supply voltage. (Lowest LET th = 12 MeV.cm 2 /mg.) The low LET threshold implies possible proton sensitivity. No SEU data for chip configured as an IEEE1355 protocol control circuit. Therefore, presence and consequences of SEFIs not known. Also, PLL not tested and it could exhibit a frequency dependence.

7. 72004 MAPLD: 141Buchner Hardware for SEE Testing Computer A NIC Computer B Extender Card ASIC (DUT) exposed to ion beam ASIC not exposed to ion beam Three cables

8. 82004 MAPLD: 141Buchner Hardware for Testing Atmel Asic Extender Card

9. 92004 MAPLD: 141Buchner Software for SEE Testing Step 1. Designate Master and Slave computers. Step 2. Start Master before Slave. Step 3. Master in each channel sends a “flow control character” to the Slave, requesting the Slave to send one byte of data back. Step 4. The Slave generates a packet consisting of a “Header” containing flow control characters followed by one byte of data (A5). Parity bits are added to flag any errors that may arise in the header or data parts of the packet. Step 5. Packet is transmitted from Slave to Master.

10. 102004 MAPLD: 141Buchner Irradiation Conditions IonLET (MeV.cm 2 /mg) Cu20.7 Kr29.3 Xe53.9 Au87.4 DUT configured to be Master and Slave. Frequencies: 6 MHz, 80 MHz, 100 MHz, 140 MHz. Supply voltage = 5.0 V.

11. 112004 MAPLD: 141Buchner Expected Errors Errors may occur in the packets, in either the header or data parts. This will be flagged by the extra parity bits used by the CRC. Errors in a packet can occur when the packet is temporarily stored in either one of the two FIFOs – one for transmission and one for reception. Errors may occur in the registers containing data used to configure the network. There are 96 such registers of which 40 can be read because they are fixed and only used once when communications are first established. The remaining 56 are dynamic and errors in those registers can cause SEFIs. Errors in the PLL can cause a loss of synchronization that results in a SEFI.

12. 122004 MAPLD: 141Buchner Results SEFIs observed at all LETs. However, only required a software restart and not a full power cycle. No latchup observed. Error rate independent of frequency. All errors appeared only in the Master independent of whether the DUT was configured to be the Master or the Slave. This is because only the Master detected errors while the Slave acted as a “dumb” terminal.

13. 132004 MAPLD: 141Buchner Results Communications were halted when one, two or three links were dropped. Only 40 of the 96 registers could be monitored for SEUs. The SEU threshold for those registers was greater than 29.3 MeV.cm 2 /mg The SEU cross-section for Link drops and Link errors is below 20 MeV.cm 2 /mg. The lower LET threshold is most likely due to errors in the PLL.

14. 142004 MAPLD: 141Buchner Results

15. 152004 MAPLD: 141Buchner Results

16. 162004 MAPLD: 141Buchner Summary and Conclusions Results of SEE testing of the Atmel ASIC 3-channel chip: –Not sensitive to SEL. –Upsets take the form of either link drops or register errors. –Error rate is not sensitive to frequency. –SEFIs require a software restart and not a power reset. –Errors have a low LET threshold, which means that the error rate must be calculated and methods implemented to immediately initiate a software restart.