Embedded Systems Conference
Breaking News
Oldest First | Newest First | Threaded View
User Rank
re: Power Tip 58: Power supply grounding--which camp are you in?
an_m   4/4/2013 6:43:14 PM
Oh yes. both are a single point star ground, one is just more distributed than the other :-) and then you have , vias and components on both sides of the board, all good fun. My mark one eye ball rule of thumb is like yours. Look at the currents, keep di/dt low. and break every other rule at some point or other

User Rank
re: Power Tip 58: Power supply grounding--which camp are you in?
Consultofactus   4/5/2013 12:21:25 PM
Much depends on the power output level of the switcher. The simplified drawing in the article shows the typical single phase SMPS chip with on-chip gate driver. With literally dozens of chips to choose from this approach reaches its practical limit around 150W. For these middle-to-lower wattage supplies a single ground consisting of a compact star ("single point") topology is adequate, but a ground plane is preferred for best EMI performance. Much above the 150W (or so) level a separate gate driver device will greatly help decouple switching transients from the SMPS chip - this is where a two-mesh power and signal ground approach is necessary. In these designs the signal ground will host the SMPS chip and associated bias and feedback scaling/filtering circuits. These larger designs also tend to be poly-phase so a separate power ground is especially important to keep the multiple high current paths away from the control circuitry. The power ground is common to the gate driver, current sense, input capacitor(s) and OVP. Of course in isolated designs like flybacks there's almost always a third isolated "ground" on the output.

User Rank
re: Power Tip 58: Power supply grounding--which camp are you in?
bikeron   4/5/2013 4:52:12 PM
Lot's of grounding issues left out in this article.. looks like a TI advert to me...

User Rank
re: Power Tip 58: Power supply grounding--which camp are you in?
Bert22306   4/5/2013 8:41:40 PM
Probabaly the reason why heated debates emerge is because no one pat rule ever seems to work across the board (ha ha, what a pun). I agree with the comment that a ground plane amounts to a large area single-point ground. Thing is, whether on a single card, or in a large system of components, I guess the one basic goal is to minimize ground currents. And the knee-jerk reaction of isolating grounds doesn't always work, to this end, because then your risk frying components when their zero volt references drift too far apart. One good solution is fiber optics.

Top Comments of the Week
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
Max Maxfield

My Mom the Radio Star
Max Maxfield
Post a comment
I've said it before and I'll say it again -- it's a funny old world when you come to think about it. Last Friday lunchtime, for example, I received an email from Tim Levell, the editor for ...

Bernard Cole

A Book For All Reasons
Bernard Cole
1 Comment
Robert Oshana's recent book "Software Engineering for Embedded Systems (Newnes/Elsevier)," written and edited with Mark Kraeling, is a 'book for all reasons.' At almost 1,200 pages, it ...

Martin Rowe

Leonard Nimoy, We'll Miss you
Martin Rowe
Like many of you, I was saddened to hear the news of Leonard Nimoy's death. His Star Trek character Mr. Spock was an inspiration to many of us who entered technical fields.

Rich Quinnell

Making the Grade in Industrial Design
Rich Quinnell
As every developer knows, there are the paper specifications for a product design, and then there are the real requirements. The paper specs are dry, bland, and rigidly numeric, making ...

Special Video Section
After a four-year absence, Infineon returns to Mobile World ...
A laptop’s 65-watt adapter can be made 6 times smaller and ...
An industry network should have device and data security at ...
The LTC2975 is a four-channel PMBus Power System Manager ...
In this video, a new high speed CMOS output comparator ...
The LT8640 is a 42V, 5A synchronous step-down regulator ...
The LTC2000 high-speed DAC has low noise and excellent ...
How do you protect the load and ensure output continues to ...
General-purpose DACs have applications in instrumentation, ...
Linear Technology demonstrates its latest measurement ...
Demos from Maxim Integrated at Electronica 2014 show ...
Bosch CEO Stefan Finkbeiner shows off latest combo and ...
STMicroelectronics demoed this simple gesture control ...
Keysight shows you what signals lurk in real-time at 510MHz ...
TE Connectivity's clear-plastic, full-size model car shows ...
Why culture makes Linear Tech a winner.
Recently formed Architects of Modern Power consortium ...
Specially modified Corvette C7 Stingray responds to ex Indy ...
Avago’s ACPL-K30T is the first solid-state driver qualified ...
NXP launches its line of multi-gate, multifunction, ...
EE Times Senior Technical Editor Martin Rowe will interview EMC engineer Kenneth Wyatt.
Flash Poll