Learning analogue fundamentals, learning to read a datasheet (probably one of the most important skills for real electronics design!), and C for embedded systems are probably the real keys here.
For a start in electronics I know of MITx with prof. Agarwal, but it's based on his well priced book. There's a load of free texts on the basic elements and circuits. The Art of Electronics is often recommended and it seems rather comprehensive, but I have not read it yet myself - you might find it in a library. I recently read a neat report on a microcontroler based switch mode power supply. Before I found several analog chip manafucturer's application notes quite interesting and advanced. Power Supply design is pretty fundamental, too, as every application needs one. The difference between ideal current and voltage sources was one of the first things to learn for me.
The point being, to address the parent post, that high power design can be a completely different beast to mixed signal (stress on signal).
As per some college rules, there are for example computer engineering, micro electronics, motor drive electronics, telecommunication sciences,and power engineering ; which are semi related fields.
* Embedded systems: mainly involves writing software but may require understanding of the hardware architecture; examples include Arduino and MSP430
* PCB design: Eagle and KiCad are good places to start
* Digital logic design: theory of how to optimize gate-level logic and how to design common digital circuitry
* HDL development: using Verilog or VHDL to implement digital designs
* FPGA design and implementation: synthesizing your HDL design to run on an FPGA
* Digital circuit design: transistor-level implementation of digital circuits, mainly used for fine-tuning high speed circuits (e.g., adders, multipliers)
* Analog and mixed-signal circuit design: same as above, but not in the digital domain (i.e., signals are not defined as 0 or 1); mixed-signal focuses on designing converters and interfaces between the analog and digital domains
* RF circuit design: high-frequency circuit design, very high barrier to entry and extremely difficult to learn