TPS1H200A-Q1 enter image description here

  1. How is does the FAULT pin work? (from what I gathered when I(lim) threshold it hit, fault is reported as FAULT = LOW. During normal operation FAULT = HIGH (no issues)

  2. How / where is the FAULT pin connected to?

  3. enter image description here

In the above image. I understood the glitch time. As per what I stated above when I(lim) threshold is hit. FAULT is reported i.e. FAULT = LOW (to indicate an issue). As per the datasheet is VFAULT HIGH equal to 0.2V? As its low value clearly seems to be 0V. enter image description here

In this case shouldn't VFAULT be HIGH for when thic(off)?

  1. enter image description here

I did not understand the terms. Say overload or short to GND (is this at the input?)

Open load or short to battery, by open load I infer that the circuit is not completed at the Source or OUT pin of the IC. 'Short to battery' is this at the input side?

Lastly the IN and OUT columns are they Input-Output Current High or Low(s) OR Voltage at Input-Output High or Low(s).


1 Answer 1

  1. Yep that's correct.
  2. You would connect the Fault pin elsewhere in your circuit as a monitor for the health of this chip. For example you might have it connected to a GPIO pin of a microcontroller that might go into a different mode if the chip faults.
  3. The FAULT signal will go low when the current limit has been hit for a longer duration than the deglitch time. When the FAULT signal goes low, the datasheet states that the voltage of FAULT will be 0.2V. The graph shown here is illustrative and therefore will not show this 0.2V level, and instead goes to zero for simplicity of the diagram. Page 1 of the datasheet has a real capture of the FAULT signal where you can see it goes to 0.2V.
  4. This is overload or short at the output. Since a short to ground is a low resistance path to ground, there would be a lot of current flow in this event, therefore an overload or a short to ground are equivalent in terms of how the regulator will react, as they are both situations where the current will be above threshold. Short to battery and open load are referring to a different state of the output circuit, in this case it is talking about having a relatively high resistance on the output. The IN and OUT columns are referring to the voltage present at the IN and OUT pins.

Edit to answer comments: I think you're confused becuase you don't fully understand what an open is. You're exactly correct in saying that for an open load, it means that the output side of the circuit isn't fully complete.

However what that means is that not very much, (or zero) current can flow through the circuit/between the two nodes. From ohms law, this would tell us that the resistance between the two points is very high, or infinite, as resistance is voltage divided by current flow. So its possible that you can have a circuit that appears to have a complete path from positive to negative through a resistor, but if it is a very high value resistance, then it may as well not be there, and have an open circuit.

In the context of this high side switch, if there was nothing connected between OUT and ground, how much current would flow through OUT? (zero!), so we call this an open load. However what happens if we attach a really big resistance between OUT and ground? (very little/zero current again). So we can see that a high resistance is an open circuit.

For your second comment: On page 12 of the datasheet it says 'a hard short-to-GND condition (when the IN pin is enabled, a short-to-GND occurs suddenly)' This just means that the short-to-GND happens quickly and not gradually (the current flow has increased beyond the limit threshold very quickly/instantaneously, rather than a slow increase)

  • \$\begingroup\$ Thanks for the clarifications; however, I'm still conflicted by the Open load or short of the battery. Say Open load; then the load part/side of ckt isn't fully complete. How would that end up High resistance. I cant understand the correlation of how it'd be high resistance. Could you explain it in terms of voltages so I could relate it with the columns too \$\endgroup\$
    – Harkirat
    Commented Apr 17, 2023 at 13:47
  • \$\begingroup\$ There's also the use of the term 'hard short' under application curves, if possible i'd like an explanation for the term. \$\endgroup\$
    – Harkirat
    Commented Apr 17, 2023 at 15:54
  • 1
    \$\begingroup\$ I've replied as an edit as I didn't have enough characters in a comment \$\endgroup\$
    – Entropy
    Commented Apr 18, 2023 at 12:46

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