Power Supply Design for Portable Animal Device: 3.3V, ±1.5V, ±20V, Efficiency, PCB Size

I need help designing a power supply for a portable medical research device for animals. My problem is designing a configuration for multiple voltages with pcb size and power efficiency in mind. I need 3.3 V, +/- 1.5 V, and +/- 20 V.

Below I’ve listed device info and estimated current consumption of both the analog and digital components.

*Device Info*: My device will be worn by small rodents and used to (1) amplify low-voltage and low frequency (< 15 kHz) analog signals, (2) output 100uA@20V constant current pulses, and (3) communicate with PC via BT. This device will be small (2’x2’ double sided pcb) and light weight. Thus, efficiency and pcb footprint are extremely important. Component cost isn’t much of a concern.

*Digital Components*:
1. MCU: 10 mA at 3.3 V (Supply Range: 1.7 - 5.0 V )
2. Bluetooth Module: 15 mA at 3.3V (Supply Range: 3.0 - 3.6 V, peak current 50mA)

*Analog Components*: All analog components use dual power supplies (+/-).
1. Section A: 1mA at +/- 1.5 V (

If you have regulated voltage levels above the supply voltage, or the need to generate negative voltages from positive supply voltages, you need a switching supply (I'll include charge pumps in this catagory). Linear regulators are used for several reasons such as simplicity, low part count, lower noise, and when you are not necessarily concerned with efficiency. Board area could be better or worse depending on how much heat is generated and how it is dissipated. LDO are linear regultors used when you don't have much headroom between your supply voltage and the regulated output.

What is your engineering background?