Parallel high-speed current driver circuit diagram composed of OPA660

The figure shows a parallel high-speed current drive circuit . The input signal Vin is added to the base B (pin 3) of the equivalent special transistor OTA in the OPA 660 device through a 180Ω resistor . The two collectors C (pin 8) are directly connected and connected to the load, while providing current to the load. , so the current flowing through the load is twice that of a single OTA, because the maximum output current of the OTA in the OPA660 is ±15mA, and the maximum output current that the parallel circuit can provide is ±30mA. When larger current is required, multiple OPA660 operational amplifiers can be connected in parallel to obtain the required load current. The external 180Ω resistor at the input end (B pole) has a current limiting effect, which can also prevent the amplifier from self-oscillation and reduce the peaking phenomenon of the frequency characteristics. The negative feedback resistor RE (tens of ohms to hundreds of ohms) connected to the emitter can improve the linearity, input impedance and stability of the amplifier and many other dynamic indicators, but the transconductance of the OTA will decrease. It can be seen from this that, Appropriately changing the resistance of RE can adjust the output current.