Reliability Evaluation of Combinational Circuits from a Standard Cell Library

Grupo de Sistemas Digitais e Embarcados (GSDE)www.gsde.furg.br

SIM 201631st South Symposium on Microelectronics

Porto Alegre, Brazil

Reliability Evaluation of Combinational Circuits from a Standard Cell Library

Ygor Quadros de Aguiar, Alexandra Lackmann Zimpeck, Cristina Meinhardt

2/30 31st South Symposium on Microelectronics

Porto Alegre, Brazil – May/2016www.gsde.furg.br

Agenda

1. Introduction2. Motivation and Objective3. Single Event Effects4. NFAS-tool5. Experiments6. Final Remarks



Introduction

New challenges introduced by tecnology scaling:❖ process variability

❖ reliability

✓ increased device failure rates

✓ low yield



Motivation

The increasingly need of EDA (Electronic Design Automation) tools for:✓ robustness evaluation of design

✓ assessment of fault tolerant tecniques

The NFAS-tool

Stuck-OnStuck-Open

Single Event Transient



Objective

Evaluate the SET effects on combinational circuits from a Standard Cell Library to explore the features

designed at NFAS-tool (Nanotechnology Fault Analysis Simulation tool)


Single Event Effects (SEE)



Single Event Effects (SEE):

Destructive:SEL (Single Event Latchup), SEGR (Single Event Gate Rupture) ...

Non-destructive:SET (Single Event Transient): combinational cells SEU (Single Event Upset): sequential cells

Fig. Single Event Upset (SEU) and Single Event Transient (SET) (Azambuja J. R., 2014)



Single Event Transient (SET)

Figura: Schematic of energy transfer as a voltage pulse (Wang, 2008)



Single Event Transient (SET)

Figura: Schematic of energy transfer as a voltage pulse (Wang, 2008)

Linear Energy Transfer:amount of energy released by a particle per unit length crossed


NFAS-tool



Injection of Transient Faults

NFAS-tool

Circuit Parameters

Fault Parameters

Netlist File

NGSpice

Netlist under faults

Fault Analysis/Log Files

Output Files from electrical simulations

(.data)



Interface - SET Injections



Reliability Analysis

- Modelo da falha SET- Inserção de Fonte de Corrente


Experiments for SET injections



Set of analysis available by the tool:

✓ influence of operating frequency;

✓ different technologies node;

✓ different SET characteristics;

✓ reliability regarding the input vectors.

Reliability Analysis



Experiments

❖ Fault injection carried on the output nodes.

➢ worst scenario

❖ Number of faults: two injections for each circuit time slot of simulation

➢ HA_X1: 22 injections,

➢ AOI21_X1: 26 injections,

➢ NAND2_X1: 12 injections.

❖ 3 combinational logic cells from a 45nm commercial Standard Cell library:



Experiments



Operating Frequency Analysis

Technology node: 45nm High Performance PTM and LET = 1 MeV-cm2/mg

Prop

agat

ed F

aults

(%)



Prop

agat

ed F

aults

(%)

Operating Frequency Analysis

Technology node: 45nm High Performance PTM and LET = 3 MeV-cm2/mg



Technology Node Analysis

Prop

agat

ed F

aults

(%)

Half Adder (HA_X1) and LET = 1 MeV-cm2/mg



~15%

>30%

Prop

agat

ed F

aults

(%)


Half Adder (HA_X1) and LET = 1 MeV-cm2/mg



Prop

agat

ed F

aults

(%)


2-input NAND (NAND2_X1) and LET = 1 MeV-cm2/mg



~35%

~41,67%

Prop

agat

ed F

aults

(%)


2-input NAND (NAND2_X1) and LET = 1 MeV-cm2/mg



Analysis of Linear Energy Transfer

Propagated Faults (%)













~3X


Final Remarks



Increased need for EDA tools regarding reliability analysis!!

NFAS-tool

✓ evaluates the reliability of combinational logic circuits under SET faults

✓ provides a set of information about the behavior of the faulty circuit elucidating the direct influence of design parameters

✓ supports the development of fault tolerant techniques more robust and efficient

Final Remarks


SIM 201631st South Symposium on Microelectronics

Porto Alegre, Brazil

Reliability Evaluation of Combinational Circuits from a Standard Cell Library

Ygor Quadros de [email protected]

Devices & Hardware

Reliability Evaluation of Combinational Circuits from a Standard Cell Library