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Copyright © Infineon Technologies 2005. All rights reserved. Analog Workshop 2005 TU München Christian Münker Infineon Technologies AG A Compact Multi-Tone Test Generator for RF ICs
Page 1 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Analog Workshop 2005 TU München
Christian MünkerInfineon Technologies AG
A Compact Multi-Tone Test Generator for RF ICs
Page 2 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Outline
BIST Concept for RF TransceiversBIST Concept for RF Transceivers
Test-Tone GeneratorTest-Tone Generator
Simulation ResultsSimulation Results
MotivationMotivation
Page 3 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Motivation for Test Improvements in RF Tranceivers
Growing contribution of test costs to production costs!!!
ReasonsSOC: more system tests have to be performed by
chip makerSlow and expensive RF – testsFalling production costs (smaller chips) but constanttester costs
Page 4 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
- Matching Chip – Board – Tester Output Power
- No direct access to supply voltages(integrated regulator) and LO signal
- Lots of failure modes (multiple VCO – Bands and division ratios)
VCO / Divider Functionality
ChallengeTest
- Difficult to measure directlyPLL Loop Bandwidth
- Long averaging times
- Complex signal analysis
- Dynamic range
Out-of-Band Spectrum (Phase Noise, Spurs)
- Long averaging times
- Complex signal analysisModulation Spectrum (Mask Conformity)
Critical Productiontests for RF Transmitters
Page 5 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Targets for RF IC BIST / BISC
Get rid of expensive and slow RF test equipmentDo not interfere with critical RF paths on-chipGenerate little area overheadDo not generate additional failure modes in test circuitry, make test circuitry testableModern CMOS technologies (130nm → 65 nm) favordigital over analog implementations
Mainly digital implementation!
BIST: Built-In Self TestBISC: Built-In Self Calibration
Page 6 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Outline
BIST Concept for RF TransceiversBIST Concept for RF Transceivers
Test-Tone GeneratorTest-Tone Generator
Simulation ResultsSimulation Results
MotivationMotivation
Page 7 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Built-In Self Test Concept for RF Transceivers
Page 8 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Test Signal Generation Using Sigma-Delta PLL
Page 9 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Simple Pattern Generator Using LFSR
PRBS generator with a sequence length of 29-1 made from a 9 Bit LFSR:
LFSR: Linear Feedback Shift RegisterPRBS: Pseudo-Random Binary Sequence
Can be easily configured for generation of shortdeterministic sequences like 01, 0001 as well!
Page 10 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Outline
BIST Concept for RF TransceiversBIST Concept for RF Transceivers
Test-Tone GeneratorTest-Tone Generator
Simulation ResultsSimulation Results
MotivationMotivation
Page 11 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Lossless Digital Integrator Oscillator
2 N x N Multipliers2 N-Bit Accumulators
Page 12 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Replace Multiplier by Sigma-Delta Attenuator
PLL has low-pass characteristic – no additional low-pass filter (LPF) needed in our case!
Page 13 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Replace N x 1 Bit Multiplier by Multiplexor
Page 14 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Digital Tone Generator Using SDM Attenuator
1 Bit Shifter (fixed)4 N Bit Accumulators
2 N-Bit Adders1 N-Bit 2:1 Multiplexor
Page 15 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Digital Multi-Tone Generator Using SDM Attenuator
Use time-division multiplexing to share hardware forseveral tones4 extra N-Bit registers needed per tone
Page 16 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Outline
BIST Concept for RF TransceiversBIST Concept for RF Transceivers
Test-Tone GeneratorTest-Tone Generator
Simulation ResultsSimulation Results
MotivationMotivation
Page 17 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Two-Tone Spectrum of Digital Sine Generator (Parallel Out)
SFDR
: ca.
60 d
B
N = 15
Page 18 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
SFDR
: ca.
60 d
B
Two-tone Spectrum of Digital Sine Generator (SDM Out)
N = 15
Page 19 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Measure Loop Characteristics Using Two-Tone Signal
Two-Tone Spectrum at PLL Output
Loop Characteristic(f3dB = 100kHz)
Page 20 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
Results
A completely digital two-tone test oscillator was implemented in a 130 nm CMOS processThe oscillator allows measurement of PLL loopcharacteristic and marker generationAdditional area forN=15 Bit, fS= 26 MHz, fOUT = 30 … 300 kHz:– 1 Tone Generator A = 0.01 mm2
– 2 Tone Generator A = 0.015 mm2
Page 21 of 21
Christian Münker
08-Mar-2005Copyright © Infineon Technologies 2005. All rights reserved.
