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MT3608 voltage regulator

A happy coincidence was the arrival of a heap of MT3608 chips in different circumstances. Firstly I had re-ordered the ubiquitous voltage regulator modules, not realising at the time that the ICs at their heart also form a part of the "Pesky Padauk Programmer Project"™ (parts one, two and three).

And so a bunch of raw chips showed up as well, some of them acquired just to see if and how to I could make a DC-DC boost converter. I have blown up a few of these ready-made modules in my time, and I'm not the only one!

My goal for this IC was to first make a successful 15V boost converter from a low voltage source, and then to see if I could maybe vary the output voltage by using a pot connected to the IC itself, and then maybe by using a PWM signal (?) feeding into the IC. 

From the datasheet comes:

The freepdk programmer uses 240k as R1 and 10k as R2 and so the voltage should be 0.6x(1+240/10)=15V. 

The tiny little fella looks great shackled onto an adapter built for an entirely different chip!

The FreePDK Padauk Programmer also uses some other components to maybe output different voltages programmatically via PWM?

The BSS84 is a PNP Mosfet (-0.13 A, -50 V) and the BSS138 (0.22 A, 50 V) is an NPN Mosfet and in this configuration with control coming from the STM32 I can only assume it turns on and off the 15V, but I was curious to see if it could also limit or control the voltage through some sort of PWM. 

The circuit diagram indicates some sort of Frankenstein Mosfet Sziklai pair, but I wasn't able to find any definitive information on this type of circuit, and my own experiments remain inconclusive, at this stage.