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Jan 21, 2025 | 
signalintegrityjournal.com | Heidi Barnes |Steve Sandler |Benjamin Dannan
Hardware engineers are learning the hard way that power integrity (PI) requires electromagnetic (EM) simulation of the printed circuit board (PCB) power delivery network (PDN). Traditional rules-of-thumb and leveraging data sheet examples are not an option as designs move from hundreds of Amps (A) to thousands. 1000 A across a 100 microhm (µΩ) PCB PDN is still 100 millivolts (mV) of IR drop and 100 Watts (W) of power dissipating as heat.
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Nov 13, 2024 | 
signalintegrityjournal.com | Steve Sandler
Recently, Picotest has had several questions from customers working to measure battery impedance. There are numerous publications and articles about testing battery impedance, even from VNA manufacturer’s such as OMICRON Lab, including a useful 2017 application note guide from Florian Hammerle.1This article will discuss some of the reasons for measuring battery impedance.
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Aug 5, 2024 | 
signalintegrityjournal.com | Steve Sandler
Core power rails are now routinely in the 1 kAmp to 2 kAmp range, requiring a power distribution network (PDN) impedance in the range of 20 µΩ to 30 µΩ. I am known for saying “Measure something you know before measuring something you do not; and of the same order of magnitude.” This makes sense. It provides a validation of your measurement setup, and it assures that the measurements you are going to make are within the dynamic range of the setup.
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Aug 1, 2024 | 
signalintegrityjournal.com | Steve Sandler |Benjamin Dannan |Heidi Barnes |Idan Ben Ezra
Designing a power distribution network (PDN) for a scalable 2000 Amp power supply presents numerous challenges. This paper will address these challenges while demonstrating how to design, simulate, and validate a scalable core power rail with a current of 2000 Amp. The most common architectures for high-current power rails utilize a 48 VDC input to reduce the current to a more manageable level.
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Mar 6, 2024 | 
electronicdesign.com | Steve Sandler |Charles Hymowitz |Rohan Phadke
Ultra-Low Impedance Test: Possibilities for the FutureWhile Picotest's P2102A probe can measure ultra-low impedances in the sub-100-µΩ range, it faces limitations. But the high ground loop resistance of the probe can be overcome using a very-high-CMRR low-noise isolator in conjunction with an ideal SHORT. Employing either a separate amplifier to boost the signal-to-noise ratio (SNR) or a vector network analyzer (VNA) with a higher dynamic range could help improve the measurement even further.
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Jan 23, 2024 | 
signalintegrityjournal.com | Benjamin Dannan |Steve Sandler
Continuing our discussion from the last two blogs, we discussed how much CMRR is required to make this measurement, and we demonstrated this measurement with a Bode 100 VNA. To recap, before making a 40 µΩ measurement, we had to create our DUT. Figure 1 depicts the DUT that was created to support this low-impedance measurement with the 2-port probe. However, when this DUT was made, it was not known precisely what the impedance of the copper on this PCB mount was.
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Jan 4, 2024 | 
signalintegrityjournal.com | Benjamin Dannan |Steve Sandler
This article is part of a two-part series. Please find part one of the series here. Let’s continue our discussion from where we left off in our last blog. If you recall, after we defined how much CMRR is required to measure a 40 µΩ (2000 Amp) PDN with a 2-port probe, we said we would show you how to make a 40 µΩ impedance measurement with the 2-port probe. Before making a 40 µΩ measurement, we need to create a DUT.
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Dec 28, 2023 | 
signalintegrityjournal.com | Benjamin Dannan |Steve Sandler
Most of us are aware of the ground loop in the 2-port measurement. Most of us are also aware that we need to introduce a ground loop isolator to correct the error. If not, we’ve published plenty on the subject. But how much CMRR do you need to add? How does the use of a probe impact this requirement? Rest assured, this measurement can be successfully performed, as shown in Figure 1, and we’ll show you how to determine much CMRR it takes in this blog.
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Nov 28, 2023 | 
signalintegrityjournal.com | Steve Sandler |Benjamin Dannan |Heidi Barnes |Christian Yots
In the world of power electronics, the focus is on the power supply, and the load is modeled as a simple resistor. In the world of power integrity, the focus is on the decoupling capacitors required for the digital load and the power supply is modeled as a simple resistor in series with an inductor.
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Feb 14, 2023 | 
dispatchist.com | Steve Sandler
Sandler was selected by his peers due to his contributions in the power integrity field, including his contributions to now standard power integrity methodologies, state-space VRM modeling, stability and worst-case analysis.'Steve's presence in the power systems industry has been felt for years, and his direction of the industry has been instrumental in the power integrity field,' says Suzanne Deffree, Group Event Director.'They are doing really great things in the power integrity sector and...
