I am using a CRD (Current limiting Diode to Bias an opamp into class a and i wish to use somthing better than a resistor in series with the diode to buffer the capacetence of the Current source and i was considering a cascode type like, as Detailed in the Burr Brown AB-007 Note. Has any one done this and what results did you get. I would like to keep the Drop-out Voltage of the curent source as low as i can since the Amp is battery operated. TIA.
Thank you for your reply. I am using a 1k resistor in series with a 1N5298 Current regulator Diode to Supply about 1.0 Ma of constant Current into the Opamp's output stage. The Opamp is driving the Input of a Open loop Buffer.My concern is that at large AC Voltage swings the CRD will drop out and Thus create more Distortion that the Class A Biasing would eliminate. So far the CRD and a 1K resistor works right up to the point of Clipping.I am also concerned that 1K may not be large enough to isolate the Capacitence.
This is why i am considering a casscode aproch to the Problem since this Topology has low Capacitence to start with and the Capacitence is more or less Constant with changing Voltage. TIA PPL
This is why i am considering a casscode aproch to the Problem since this Topology has low Capacitence to start with and the Capacitence is more or less Constant with changing Voltage. TIA PPL
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