portable radio circuit problem

[yuenkit]

Hi,


I am looking for the circuit for superheterodyne fm radio, which can be powered by 1.2V AA rechargeable battery.

most of the circuit i found are 1.5V or 3V. I wonder, could I use a dc-dc voltage converter for it?


Thank you.

 

[Russlk]

I don't know any IC that works down to 1.2 volts, but try this circuit. It is called a blocking oscillator and is configured as a voltage boost. I don't know what the output voltage would be, you will have to experiment with values for R and C. If it doesn't work at first, try changing the connection to either the pri or sec.

 

[audioguru]

Texas Instruments' TPS61010 boost converter IC works down to 0.8V, has 100mA or more output current (for a small power amp), is very efficient and has a regulated output voltage. Digikey has stock for $2.48US.