Low-input-capacitance-buffer


Posted on Oct 2, 2012

Ql and Q2 constitute a simple, high-speed FET input buffer.·Ql functions as a source follower, with the Q2 current-source load setting the drain-source channel current. The LT1010 buffer provides output drive capability for cables or whatever load is required. The LTC1052 stabilizes the circuit by comparing the filtered circuit output to a similarly filtered version of the input signal. The amplified difference between these signals is used to set Q2`s bias, and hence Ql`s channel current.


Low-input-capacitance-buffer
Click here to download the full size of the above Circuit.

This forces Ql"s V0 s to whatever voltage is required to match the circuit"s input and output potentials. The diode in Ql"s source line ensures that the gate never forward biases and the 2000-pF capacitor at Al provides stable loop compensation. The rc network in Al "s output prevents it from seeing high-speed edges coupled through Q2"s collector-base ]unction. A2"s output is also fed back to the shield around Ql "s gate lead, bootstrapping the circuit"s effective input capacitance to less than 1 pF.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Wide band 10MHz 500MHz RF amplifier
Mini Amplifier Using Lm1895N Circuit
arduino Sharp IR distance sensor outputting consistently high voltage
Serial programmer circuit for AT89Sx MCUs
battery desulphation progress
Automatic LED Emergency Light Circuit
stabilised power supply current limiting
Build a FM radio transmitter
6 Battery Tesla Switch Circuit Mosfet Solid Stat
Simple VHF FM radio
555 lights remind
Integrated voltage regulator circuit diagram 5G317 TV application
External protection signal generator by a circuit diagram TDA4866



Top