Design and key Parameter Analysis of High Speed and Large Current Pulse Width Adjustable Pulse Constant-Current Source

By studying the working principle of constant current source circuit for airbag ignition test, a pulse constant current source with negative feedback of base current and voltage is designed. The key parameters in the analysis period include: the influence of the voltage swing rate of the operational amplifier, the parasitic capacitance of the MOS tube and the on-off resistance on the establishment time of the output current of the pulse constant current source. The experiment shows that the selection of appropriate devices can meet the requirements of airbag ignition test, the output characteristics of constant current source circuit can meet the requirements of 0-10A adjustable, the frequency 0-5khz adjustable, and the establishment time is less than 50 µ s