My board can use either 2 or 3 1.5V battery cells. My input voltage is therefore between 2.6 and 4.6V. The radio module can only handle 2.4V to 3.8V, so I need to clamp this voltage to 3.8V (or preferably 3.3V).
If I use a 3.3V very low quiescent current LDO regulator, and the input voltage is 2.6V, will the pass transistor be turned on so that 2.6V (minus the LDO drop) appears on the output (at 0 - 40mA output current range)? The radio module will be asleep most of the time but when transmitting or receiving could take 18mA or so.
The LDO I'm thinking of using has versions working down to 1.2V, so I think that the logic inside will be functional and the pass transistor will turn on since the output is less than the desired output. Any thoughts?
Thanks!
Mark.
If I use a 3.3V very low quiescent current LDO regulator, and the input voltage is 2.6V, will the pass transistor be turned on so that 2.6V (minus the LDO drop) appears on the output (at 0 - 40mA output current range)? The radio module will be asleep most of the time but when transmitting or receiving could take 18mA or so.
The LDO I'm thinking of using has versions working down to 1.2V, so I think that the logic inside will be functional and the pass transistor will turn on since the output is less than the desired output. Any thoughts?
Thanks!
Mark.