I have a 9V carbon-zinc battery and the ICs in my circuit works on two vaoltage levels
RF modules work on 2.7v to 3.3v
microcontroller works on 5v
I want an IC to which i can give this 9v input and get my desired out put for my ICs.
I searched the net but confused in terminologies Linear regulator,LDO,DC-DC converters and many more
Can some one help me in selecting this IC?
if a single IC can do both conversions its good but if not 2 seperate ICs can also be used but either it is 1 IC or 2 ICs the total cost for this conversion should not be more than $6.
I will be purchasing these ICs from www.Digikey.com so if possible plz confirm that the IC you are suggesting is available with the distributor(They have very good online database)
The linear regulators will work for your system. The low drop out will allow the battery to be used longer. Linear regulators are not very efficient. Switching regulators are more efficient but cost more and take more skill to design and test.
If you use linear regulators. You can use the 7805 (fixed 5 volts regulator). There are many variations, just select one according to the current you need. If it is low enough you can use a 78L05.
For the other voltages one choice is the LM317 ( adjustable from 1.2 volts and up).
These are available anywhere including digikey.
Or you may use Low Dropout units. Same concept but they require less input voltage to deliver the output voltage.
K
i would suggest that you should use LDO regulators as what your application(wireless) required.
LM317(adjustable reg) and 78L05(fixed 5V reg) are cheap and easy to use, BUT they are linear regs that consumes more power compared to LDO/ISR(switching regulators).