Embedded Systems Conference
Breaking News
Newest First | Oldest First | Threaded View
User Rank
re: Calibrate a power supply with a digital potentiometer
BicycleBill   2/17/2012 9:18:34 PM
Certainly, it's not a solution to every design situation, but it gives you new degrees of freedom and flexibility--and along with that, comes responsibility!

User Rank
re: Calibrate a power supply with a digital potentiometer
sharps_eng   2/17/2012 8:05:21 PM
Agreed - replacing a hardware device with a digital pot which contains a bunch of registers, non-volatile or not, increases the state complexity of the system. It may make a better system, but it makes a different system which needs to be tested differently. The ESD /EMI compliance issue is just one manifestation of this. Also: make sure you choose the right version of the pot chip, you don't want your systems to be powered up first time, set at the wrong end of the pot when you want it to be set in the middle.

User Rank
re: Calibrate a power supply with a digital potentiometer
stricula   2/16/2012 8:54:31 PM
Had a colleague try this in a design. Worked well until ESD testing. Just wanted to present that potential pitfall. Ended up re-purposing that digital pot control output to PWM into an RC filter. The RC filter output was connected to a resistor which went into the feedback node of the regulator. The micro was always reading the voltage out of the regulator. It was an obvious solution once realized that the feedback node is ideally a fixed voltage; lower value than specified = more power commanded out. Makes for an easily configurable and adjustable power supply.

Most Recent Comments
David Ashton
sw guy
Brian Fuller2
Why Connect a Car?
May 11, 1pm EDT Monday
Overview: Battle-hardened veterans of the electronics industry have heard of the “connected car” so often that they assume it’s a done deal. But do we really know what it takes to get a car connected and what its future entails? Join EE Times editor Junko Yoshida as she moderates a panel of movers and shakers in the connected car business. Executives from Cisco, Siemens and NXP will share ideas, plans and hopes for connected cars and their future. After the first 30 minutes of the radio show, our listeners will have the opportunity to ask questions via live online chat.
Top Comments of the Week
Flash Poll
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Special Video Section
LED lighting is an important feature in today’s and future ...
Active balancing of series connected battery stacks exists ...
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 ...