We are evaluating using the MP100L
The issue we have seen that the MP100L will not start-up with resitive load of 2.2 komh (Vout is 3.3V without this load - only 26kohm feedback resistor load)
In our application we have 230VAC input that is full-wave rectified
Vin on the MP100L Vin (pin 8) is connected to this full rectified voltage
(a 47nF x2 capacitor is connected between line and neutral before the full-bridge)
VB/VD (pin 3/5) is connected to 4*10uF 50V/X7R capacitors (effective capacitance for the charging voltage ~20uF).
The ouptut voltage (3.3V) is set using 16kohm resitor between Vout(pin 4) and VFB (pin6) and a 10kohm resitor between VFB (pin7) and GND.
Vout is also connected to a 1uF output capacitor.
With no load (apart from the feedback resistors) the output voltge rise to ~3.3V
If a 2.2 kohm resitor is connected between the Vout and GND the output voltage rise to about 0.4V.
It seems that there are some internal over-current or something not mentioned in the datasheet that stop regulation of the output voltage to the valid value of 3.3V.
The output current of a 2.2komh resistor at 3,3V is 1.5mA, the values used in our application should really be able to support this
Any suggestions ?