Fast slewing amplifier using dynamic current mirrors

摘要

An amplifier input stage solves the problem of response to large signal (slewing) conditions being limited by the amplifier being dependent on constant current to charge capacitances at certain nodes in the amplifier. In general, in order to achieve faster slewing one must undesirably provide more quiescent current. Instead, by providing dynamic current sources for driving transistors in the amplifier input stage, a low level of quiescent current is maintained while a high output level of current is provided during slewing. This allows rapid charging/discharging of the capacitances at nodes in the amplifier signal path, while conserving power.