Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

What happens of DCDC module is operated outside of Vin range?

Status
Not open for further replies.
T

treez

Guest
Hi
Does anyone know what would happen if the NXJ1S1215 DCDC module is operated with Vin between 13.2V and 15V? (the datasheet says that the recommended operating range for Vin is 10.8V to 13.2V)
We never operate the device above a third of its maximum power. Most of the time we have it on 10% load.
The datasheet states that 15V is the absolute maximum for Vin.
The datasheet does not state whether the limitation to less than 13.2V comes from potential device premature failure, or just whether its output goes out of regulation or out of ripple spec. (we don’t mind loads of ripple, and we dont mind if the Vout has wide tolerance)

NXJ1S1215 DCDC module datasheet
https://power.murata.com/data/power/ncl/kdc_nxj1.pdf
 

Ask Murata for advice. Clearly they specify the voltage range for a reason, it is probably more to do with internal component voltage ratings than overheating so I doubt if duty cycle plays much part in it's rating.

Brian.
 
  • Like
Reactions: treez

    T

    Points: 2
    Helpful Answer Positive Rating
The output voltage can't go "out of regulation" because the modules are unregulated. Output voltage is proportional to input in the first order.

Apart from this point, I won't expect a useful answer.
 
  • Like
Reactions: treez

    T

    Points: 2
    Helpful Answer Positive Rating
Hi,

I assume they are unregulated DCDC converters. (see: Line Regulation)
Less input voltage --> less output voltage.
higher input voltage --> higher output voltage.

But higher voltage may also cause:
* core saturation (increased current peaks, spikes, higher noise higher EMI, maybe overheat...)
* any semiconductor or capacitor may be out of voltage specification.


Klaus
 
  • Like
Reactions: treez

    T

    Points: 2
    Helpful Answer Positive Rating
Low line at some point will enter undervoltage lockout; there
may also be some region where UVLO starts to "motorboat",
toggling in and out of operation.

High line is probably a stackup of reliability ratings from the
active and passive components set; everything from the
ICs and FETs, to the filter caps has to be respected in
the assembly rec max / abs max ratings.
 

If (and I mean IF) it works, very likely it will see its operating life significantly reduced.
 

Hi,

The circuit is like mobile charger.. same transformer methodology is used here i think (see REPEATED HIGH-VOLTAGE ISOLATION TESTING)
So there may be direct impact on the xformer out by VIN, also the ratings of components is crucial.. Datasheet is not talking about whats inside..
You know that working on absolute maximum limit may cross it, which will directly damage or reduce its life..
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top