Electronic – Improve RF range with a boost converter

boostRF

This might be a stupid idea, but I will try anyways:

I have a RF 433MHz TX module (datasheet) which can be supplied with 1.5V…12V. My understanding is the range increases with higher voltage as the module can draw more power.

My power supply is a 5V 10W wall adapter. Suppose I cannot simply change that to a 12V adapter.

If I increase the voltage from 5V to 12V using a boost converter, or a charge pump, would that have the same effect as having a 12V supply in the first place? Can the RF TX really draw more power through a boost converter?

Best Answer

To answer your questions: yes, you can, in general, deliver more power to a load, if you insert a boost converter between source and load and yes, in this specific case, the RF module will probably transmit with a higher RF power, if you insert such converter. It is hard to tell, because the datasheet is quite poor. However, both switching and (especially) charge-pump converters produce a lot of noise, at their outputs. Forget about charge pumps. If I used a switching converter there, I'd probably insert a low-dropout linear regulator (LDO) between the switching converter and the RF transmitter, to have a cleaner supply.

Also, by inserting a boost converter, you do increase the power that you can deliver to the load, but only up to the limit given by maximum power that your wall adapter may deliver (10 W in your case). In this case, the maximum power that the RF module may admit at its input (which is 12 V ยท 8 mA = 96 mW) is well below that 10 W limit, so that number will not limit anything.