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This is buck regulator I am using for 1.8 V output: TPS62067.

Input Voltage = 3.3 V

Maximum rated current = 2 A.

How the regulator will behaving if the load current increases more than 2 A ?

My understanding from the datasheet is, there will be thermal shut down when the junction temperature exceeds more than 150 C. Also module will be in shut down mode for EN pin is at logic low.

Basically I am looking for a case of over current shut-down of the module and how much time (of course in micro seconds range) it will take the module to shut down.

Edit: Added the circuit diagram, enter image description here

From the datasheet, I could not find anything as over current shutdown. Please let me know if there any further information required.

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    \$\begingroup\$ A circuit diagram is required. \$\endgroup\$ – Andy aka Apr 20 '18 at 9:51
  • \$\begingroup\$ @Andyaka, added the circuit diagram, hope this will is fine for analysis \$\endgroup\$ – vt673 Apr 20 '18 at 9:55
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From the datasheet: "The current-limit comparator also turns off the switch in case the current-limit of the high-side MOSFET switch is exceeded. After a dead time preventing shoot-through current, the low-side MOSFET rectifier is turned on and the inductor current ramps down. The current flows now from the inductor to the output capacitor and to the load. The current returns back to the inductor through the low-side MOSFET rectifier. The next cycle is initiated by the clock signal again turning off the low-side MOSFET rectifier and turning on the high-side MOSFET switch."

Sound like your normal cycle-by-cycle overcurrent limiter. You need to provide oscillograms if you mean your device is not behaving this way.

enter image description here enter image description here

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  • \$\begingroup\$ thanks for the response. I understood from your comment, maximum output rated current is 2.3 A. And as you mentioned, this is a cycle by cycle over current limiter, Is there any way we could find the speed of the cycle? Is it will be same as the switching frequency (3 Mhz) \$\endgroup\$ – vt673 Apr 20 '18 at 10:41
  • \$\begingroup\$ @vt673 They didn't use the magic phrase cycle-by-cycle, but I interpreted it that way. \$\endgroup\$ – winny Apr 20 '18 at 11:20
  • \$\begingroup\$ I understood that :-). But I was curious about the intervel at which MOSFETs are turned on and off \$\endgroup\$ – vt673 Apr 20 '18 at 12:35
  • \$\begingroup\$ 3 MHz. Says in the datasheet. \$\endgroup\$ – winny Apr 20 '18 at 12:41

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