Just a quick schematic of the project:

View attachment 128889

Just connect the pot wiper (not shown) to common.

 

Or you could put 560 ohms where D2 is.
Or make the pot 2K and place that in series with 8.2K 5% or 8.87K 1% for a finer range of adjustment.

These are not important changes. Just options, mostly to demonstrate the kind of fine tuning methods that come from experience in designing analog circuits.

Thanks, that'll be v2.0 I think.

 

Just connect the pot wiper (not shown) to common.

Thanks, yes, I did read up on that but didn't show it on the diagram, I only used a generic resistor diagram

 

Just a quick question while i'm here, the n-channel mosfet, the 3 pins are S, D & G.

I can see the G goes to GATE but am I correct in thinking that the D goes to V-OUT & S to V-IN?

 

If the drawing is right, source is the output. Source is always where the elbow of the gate is drawn...and the connection to the little pointy thing.

 

I can see the G goes to GATE but am I correct in thinking that the D goes to V-OUT & S to V-IN?

That would be true for a P-MOSFET but this is an N-MOSFET so the source (S) is the output (as shown).
The LTC4365 has a built-in charge pump to generate the required gate voltage above the input voltage to fully turn on the N-MOSFET in a source output configuration.

 

...little pointy thing.

love it, thanks chap.

 

Just connect the pot wiper (not shown) to common.

Is this correct - pins labelled for ease?

 

Is this correct - pins labelled for ease?View attachment 128902

The wiper can be connected as shown or to ground.
Typically you want a clockwise turning of the pot knob to increase the trip voltage (reduce the resistance).
For that you need to know towards which end (1 or 3) the wiper moves with rotation (usually shown in the pot data sheet).
If you don't care which pot knob direction increases the voltage then the connection shown will certainly work.

 

The wiper can be connected as shown or to ground.
Typically you want a clockwise turning of the pot knob to increase the trip voltage (reduce the resistance).
For that you need to know towards which end (1 or 3) the wiper moves with rotation (usually shown in the pot data sheet).
If you don't care which pot knob direction increases the voltage then the connection shown will certainly work.

Looks like it's clockwise from 1 to 3: http://docs-europe.electrocomponents.com/webdocs/15aa/0900766b815aa64c.pdf

So I am good yeah?

Would it function any differently connecting the wiper to GND?

 

Looks like it's clockwise from 1 to 3: http://docs-europe.electrocomponents.com/webdocs/15aa/0900766b815aa64c.pdf

So I am good yeah?

Would it function any differently connecting the wiper to GND?

Connecting as you show will increase the resistance for a clockwise rotation, reducing the trip point voltage.

Connecting the wiper to ground will do the opposite.

 

Connecting as you show will increase the resistance for a clockwise rotation, reducing the trip point voltage.

Connecting the wiper to ground will do the opposite.

Thank you.