For my senior design project, I am trying to generate two voltage levels or rails from a battery powered circuit (12 V and 3.3 V.)
I am using an adjustable boost converter for the 12V rail and a fixed one for the 3.3 V.
The battery is a Li-ion 3.7 V_nom, 2200 mAh from Tenergy.
The boost converter is the ADP1613 and I also have a backup, the LM2735.
The 3.3 V is the LD3985M33R (buck.)
The loads I will be powering with the 12 V rail are:
An electromagnet that draws a max of 450 mA according to the manufacturer (but in testing measured 150 mA)
4 strings of of 4 LEDs, running at 20 mA each, which puts each string at around 80 mA (the forward voltage is around 2 V for each LED)
The bias voltage of an audio amplifier, the LM386N.
The 3.3 V is powering:
An LED driver.
When I connect any load to my boost converter, the voltage output drops significantly.
For the electromagnet, it drops to around 4 to 5 V.
With the LEDs, it drops to around 7 to 8 V.
For the audio amplifier, it drops to around 6 to 7 V.
Unloaded, the boost converter provides around 12 V.