O
Opps
Guest
Hi, I am using the following basic and simple circuit to bias a sine
signal:
R3
+/\/\/\+ Vcc
/ R1
\
_+_ GND
with C=50pF and R1=50Ohm to match the impedence of the signal generator and
to avoid the DC reach its output. Well I adjust R2 and R3 for the correct
bias.
Now I need to build a current source driven proportionally with this voltage
signal.
I have signal up to 150MHz, current up to 350mA and the load is a LED. Which
transistor can I use? In which configuration? Well.... in which manner can I
optimize the LED driving considering that their resistence and capacitance
can limit the bandwidth of the circuit?
Thanks,
Ale
signal:
R3
+/\/\/\+ Vcc
\ R2-- INPUT -- ||------+------------+------------------------> OUT
C | +/\/\/\+ GND
/ R1
\
_+_ GND
with C=50pF and R1=50Ohm to match the impedence of the signal generator and
to avoid the DC reach its output. Well I adjust R2 and R3 for the correct
bias.
Now I need to build a current source driven proportionally with this voltage
signal.
I have signal up to 150MHz, current up to 350mA and the load is a LED. Which
transistor can I use? In which configuration? Well.... in which manner can I
optimize the LED driving considering that their resistence and capacitance
can limit the bandwidth of the circuit?
Thanks,
Ale