Patent ID: 6088206
Filing Date: 2000-07-11
Classification: H03K

Abstract:
An off-chip driver circuit comprising:a first N-channel field effect driver transistor having a gate, a source, and a drain;input signal means coupled to the gate of said driver transistor for sending a selected signal to the gate of said driver transistor;an output connected to said drain of said driver transistor; anda clamping circuit for limiting the overdrive of said driver transistor coupled between the source and the gate of said driver transistor for minimizing ground bounce and noise on the output connected to the drain of said driver transistor comprising:a current source:a resistor with a first connection to ground and a second connection to said source of said first driver transistor for generating a source-follower potential at said source of said first driver transistor during the application of an input signal from said signal means to the gate of said first driver transistor;a second N-channel transistor having a gate, a source, and a drain, said gate and drain being interconnected to cause said second transistor to simulate a diode and said source of said second transistor being connected to ground;a third N-channel transistor for regulating the output signal of said driver transistor, said third transistor having a gate, a source, and a drain, said source of said third transistor being connected to ground;a capacitor with a first connection to said source-follower potential and a second connection to said current source and to the gates of said second and third transistors, anda connection from said drain of said third transistor to said input signal means and to said gate of said driver transistor.