Patent ID: 7239184
Filing Date: 2007-07-03
Classification: G05F,H03F

Abstract:
1. A voltage-to-current (V/I) converter comprising: a positive supply rail; an input terminal operable to receive a control voltage; an output terminal operable to provide an output current corresponding to the control voltage; an op-amp including an inverting input terminal, a non-inverting input terminal, and an output terminal; a transistor including a gate terminal, a source terminal, and a drain terminal, wherein the gate terminal is coupled to the output terminal of the op-amp; a first voltage divider circuit including a first resistor, a second resistor, a third resistor, and a fourth resistor, wherein the source terminal of the transistor is coupled to a junction of the third and fourth resistors, wherein the fourth resistor is also coupled to the positive supply rail, wherein the inverting input terminal of the op-amp is coupled to a junction of the second and third resistors, and wherein the second resistor is coupled to the first resistor and the first resistor is coupled to the input terminal of the V/I converter; and a protection circuit coupled to the transistor to prevent over-voltage and over-current conditions, the protection circuit including: