Atlas insertion loss installation – (View large image or Delta-L 3 testing video)

PCB insertion loss test:  (For Delta-L 4.0 with Eigenvalue method please refer to Atlas Si for VNA)
Supports Delta-L, Delta L 3 Line, SPP, SET2DIL & SET2SEIL test methods for differential and single ended insertion loss
– including Bidirectional SET2DIL.

(Click Atlas Delta-L 3 testing if you are unable to view the video above)

The Atlas insertion loss measurement system

The Atlas insertion loss measurement system is designed to assist PCB fabricators in the accurate and repeatable measurement of PCB transmission line losses in a PCB production environment. The system comprises Atlas Si for TDR or Atlas Si for VNA.

New customers requiring insertion loss testing should consider Atlas Si for VNA.

Testing transmission line losses in the production environment

Polar Atlas software enables PCB fabricators to test PCB transmission line losses in a tightly controlled production environment. Atlas employs mathematical processing techniques** to extract frequency dependent loss characteristics when used in conjunction with suitably designed test coupons and Atlas precision GHz probe assemblies.

Atlas packages interface either with (* now discontinued) industry standard Tektronix DSA8300 or DSA8200 oscilloscope TDRs. Fabricators can choose to add Atlas to their existing Tek DSA or alternatively Polar can supply a turnkey package.

Atlas supports multiple test methods including Delta-L, Delta-L 3 Line, SET2DIL (Single-Ended TDR to Differential Insertion Loss) for extraction of differential insertion loss and effective Er from a single ended test and suitably designed coupon, SET2SEIL method (Single-Ended TDR to Single-Ended Insertion Loss) for single ended insertion loss testing and SPP (Short Pulse Propagation) methods as called for in IPC-TM-650

Atlas includes a high reliability intelligent ESD protection module with dynamic probe contact sensing and uses 26GHz high reliability RF relays to ensure optimum signal integrity.

Atlas 800 SET2DIL & SPP ESD Protection Module (click to view original size)

At GHz frequencies the measurement of PCB transmission line losses becomes inherently more challenging and in order to extract accurate measurements the signal integrity of the whole measurement system needs to be taken into account, from measurement instrumentation through the signalling cable and probe interconnect and finally through the launch structure of the test coupon and test trace itself.

The Atlas insertion loss measurement system

Atlas software is designed to assist PCB fabricators in the accurate and repeatable measurement of PCB transmission line losses in a PCB production environment.

Atlas is available in multiple configurations, for Delta-L, Delta-L 3 Line, SET2DIL, SPP and bundled SET2DIL & SPP; each configuration contains all the cables, probes and accessories including a set of 5 known good SET2DIL coupons for initial setup and training. Please contact Neil Chamberlain for more assistance.

Ergonomic probe housing:

Feedback from early adopters of Atlas has led us to tool up for a new "mouse style" ergonomic probe housing (pictured below) for the precision GGB probe.

Ergonomic GGB probe housing – (click to view original size)

Bandwidth monitoring

Unlike testing lossless controlled impedance traces, where measurement is broadly independent of system rise time, the testing of insertion loss lines means that system rise time becomes critical to quality high frequency measurements; Atlas tracks system risetime and monitors the system bandwidth. Atlas uses mathematical techniques to extract insertion losses (Sdd21) on ultra high speed differential PCB traces.

Test methods for insertion loss (attenuation) measurement

New high speed silicon families, such as XAUI, PCI Express Gen2.0, USB 3.0 and other high speed silicon increasingly deploy high speed differential signaling techniques that push system speeds above the traditional ceiling for FR4. Advanced signal processing is used to recover the signals from PCB traces which will lose most of the signal energy in transit across the PCB. Designers need to ensure the losses remain within the signal extraction capabilities of their chosen chipset. This has led to an industry requirement for a consistent test capability for insertion loss.

Delta-L

Atlas supports the Delta-L technique (v16_04 fully incorporates rev2p31 of Delta-L with the current settings and parameters) which uses long-line short-line measurement combined with innovative via de-embedding techniques, Delta-L provides a sound method for removing the via effects from differential (mixed mode) s-parameters when characterising raw PCBs for insertion loss.

SET2DIL/SET2SEIL

Atlas test methods also include both the SET2DIL (Single-Ended TDR to Differential Insertion Loss) and SET2SEIL (Single-Ended TDR to Single-Ended Insertion Loss) test methods for extracting differential insertion loss from single ended measurements.

SPP – Short Pulse Propagation

SPP allows extraction of PCB electrical characteristics that impact signal propagation; it uses your existing TDR/TDT equipment and produces frequency dependent parameters such as the propagation constant (alpha, attenuation and beta, phase constant) and effective dielectric constant along with the characteristic impedance (including even and odd mode impedance.) Atlas measurements include launch point extrapolation/long line regression fit.

In addition, SPP is available with physical or emulated IFNs (Impulse forming networks). The emulated IFNs increase usability, give enhanced signal / noise ratio and overall a reduction in package price. Please consult the board specifier before ordering in case the design authority mandates the use of physical IFNs.

Controlled impedance test

Atlas GHz test software is also capable of traditional lossless controlled impedance test; however, Polar recommends the CITS880s as your primary solution for lossless impedance test owing to the lower inherent running costs. (The fast risetimes dictated to measure insertion loss at multi GHz speeds mean that ESD control needs to be of the highest level in an Atlas environment to minimise the running costs – precision fast rise time TDR sampling heads are sensitive and more easily damaged by ESD.)

PC Specifications: See Application Note AP605 for Atlas software system requirements.

Atlas Licensing: FlexNet key protected.

Availability: Atlas Si is now released and shipping. Consult AP608 for the latest version.