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For the green LED, I'm using a 20 kΩ resistor. I have these diagrams that suggests the green LED should be connected to VOUT- and VOUT+:

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And then this diagram suggests it should be connected to TRIG/PWM and VOUT-:

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Which is the right one? Should it be connected to VOUT- and VOUT+ or TRIG/PWM and VOUT-?

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This is also the completed diagram that I came up with. I'm hoping it's correct.

The MOSFET board is this one: 15A 400W MOSFET Trigger Switch Drive Module PWM Regulator Control Panel

It looks like this:

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enter image description here

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The trigger source for the VOUT+ is rated at between DC 3.3 V - 20 V).

LEDs I'm using:

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    \$\begingroup\$ Can you draw a schematic with the tool, that diagram is hard to read, edit your question and click on the circuit editor button \$\endgroup\$
    – Voltage Spike ♦
    Commented Jan 5, 2023 at 20:17
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    \$\begingroup\$ Can you draw a proper circuit diagram including all the dead-bug ICs in the upper block and please show where the MOSFET is meant to be and what connects to its gate. What is a MOSFET board btw? \$\endgroup\$
    – Andy aka
    Commented Jan 5, 2023 at 20:30
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    \$\begingroup\$ Seems like a personal preference type thing. Since the green LED just indicates when the device is ON. You could connect it to TRIG/PWM and VIN- or connect to VOUT- and VOUT-. Both would achieve same goal. Current limit resistor depends on current you need, voltage source you have. Note that connecting LED from TRIG/PWM and VOUT- would also work but not very typical arraignment. \$\endgroup\$
    – Leoman12
    Commented Jan 5, 2023 at 21:34
  • \$\begingroup\$ Ok, I got it. Thanks. And for the momentary push button switch/tactile switch, the negative wire should go to TRIG/PWM and positive goes to VIN+? \$\endgroup\$
    – rumpled105
    Commented Jan 5, 2023 at 21:38
  • \$\begingroup\$ Yeah that should work fine for the momentary button. \$\endgroup\$
    – Leoman12
    Commented Jan 5, 2023 at 22:14

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The LED should be connected to VOUT+(Anode) and VOUT-(Cathode). The TRIG will "open" and "close" the MOSFET. The actual circuit probably looks something like this (need LED part number and VOUT+ for exact circuit limiting resistor):

schematic

simulate this circuit – Schematic created using CircuitLab

You first need to make sure the LED is rated for your VOUT+ though. If it isn't, then use Trig (that's probably a 3.3v or 5V signal) maybe. just need to make sure whatever is producing the "TRIG" siganl, can source the amount of current that the gate of the MOSFET and your green LED will consume. Part numbers for all of these items would be helpful, as well as the voltage level of VOUT+

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  • \$\begingroup\$ Okay, and for the momentary push button switches, negative wire should go to TRIG/PWN and positive goes to VIN+? \$\endgroup\$
    – rumpled105
    Commented Jan 5, 2023 at 20:58
  • \$\begingroup\$ I believe the Vout- would really be the drain terminal of mosfet. \$\endgroup\$
    – Leoman12
    Commented Jan 5, 2023 at 21:24
  • \$\begingroup\$ @Leoman12 if it is a low side switch using a Nchannel MOSFET, the potential difference of the source has to be lower then the drain. \$\endgroup\$
    – PhippsTech
    Commented Jan 6, 2023 at 4:36
  • \$\begingroup\$ @Code Phipps, Yes true. What I meant is that it looks like based on the configuration of the PCB, they have VOUT- as the Drain terminal since they connect a LOAD device from VOUT+ to VOUT-. If VOUT- was simply GND terminal, MOSFET would serve no purpose since LOAD is connected directly to power rails always and not in series with low side switch. see here m.media-amazon.com/images/I/41pgmQthDRL.jpg \$\endgroup\$
    – Leoman12
    Commented Jan 6, 2023 at 14:37
  • \$\begingroup\$ @Leoman12 The DC- and DC+ is your DC supply voltage and VOUT+ and VOUT- is your load connections. The MOSFET is in series with VOUT+ and VOUT- . Makes no sense for you the VOUT- to be tied to the drain. "-" in DC systems usually points to a ground connection. Therefore, MOSFET will not operate if the Drain is more negative than the source. \$\endgroup\$
    – PhippsTech
    Commented Jan 9, 2023 at 20:32

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