Patent ID: 7119600

Claim:
A receiver circuit with a high supply voltage and operable with additional circuits operating at a low supply voltage, the receiver circuit comprising: a first differential input signal controlling a first current switch; a second differential input signal associated with the first differential input signal controlling a second current switch; a top current supply connected to the high supply voltage for providing a current to be passed either through a first current path containing the first current switch and a first bottom current supply, or a second current path containing the second current switch and a second bottom current supply; a first current-to-voltage converter connected to the low supply voltage and in series with the first bottom current supply; and a second current-to-voltage converter connected to the low supply voltage and in series with the second bottom current supply; wherein the top current supply, the first and second bottom current supplies are controlled to assure the current passing either the first or second bottom current supply is higher than the current passing the top current supply, thereby ensuring a first voltage drop across the first current-to-voltage converter to generate a first differential output signal, and a second voltage drop across the second current-to-voltage converter to generate a second differential output signal; and wherein the at least one of the first or the second current switches is a thick oxide transistor and at least one of the first or the second bottom current supplies is a thin oxide transistor.