Hi,

I wish to switch off (less than a couple uA) an IC when not in use. I am currently using a MOSFET, but it's expensive for my design. I have never seen a BJT used for this purpose before. Is there any reason I cannot do so? See the circuit Below:



Basically, Vcc is 15VDC. The IC is a MOSFET driver that switches a motor at high speed. I believe the driver uses about 10mA during normal use. The inputs (DRV1 and DRV2) don't matter to my question. ON is a +10VDC drive and OFF when near 0V. The BJT can be any transistor, but operation is fairly infrequent (once every few hours). I think something like a 2n3904 can supply way more than 10mA that I need.

Can a general purpose BJT be used without adding noise or other negative effects? I know that the Vcc voltage level may decrease a little to the IC, but this is OK.

Thanks for your help
Bruce