Resistorless voltage controlled oscillator

摘要

The VCO (16) includes a capacitor (44) which receives an input voltage level at a first terminal and a first voltage supply at the second terminal. A first transistor (46) receives the first voltage supply at a first current electrode with a control electrode coupled to the first terminal of the capacitor and a second terminal coupled to an intermediate node. A current source (50) is coupled to the intermediate node and is responsive to a first control signal. A current sink (62) is coupled to the intermediate node and is responsive to a second control signal. A current controlled oscillator (74) is coupled to the intermediate node and generates a periodic clocking signal in response to the current sourced at the intermediate node.