US 6,271,725 B1 · Low voltage bipolar transconductor circuit with extended dynamic range

Abstract

A low voltage bipolar transconductor circuit with extended dynamic range is disclosed. The transconductance circuit provides a differential current output signal and generally comprises a first and a second differential pair of transistors coupled to a differential input signal and to a load, and having transistors area ratios of 1:r and r:1, respectively. The transconductance circuit further comprises at least one first pair of diodes having positive nodes coupled to each other and to the load, negative nodes coupled to the first differential transistors, and a diode area ratio of r:1, and a least one second pair of diodes having positive nodes coupled to each other and to the load, negative nodes coupled to the second differential transistors, and having a diode area ratio of 1:r.

Claims14

Dependent claims

A transconductance circuit, comprising:

a first and a second differential pair of transistors having transistors area ratios of 1:r and r:1, respectively, said first and second differential pairs of transistors having bases and collectors coupled to a differential input signal and to a load, respectively, said first and second differential pair of transistors providing a differential current output signal;
a first pair of diodes having positive nodes coupled to each other, said first pair of diodes having negative nodes coupled to emitters of said first differential pair of transistors, said first pair of diodes having a diode area ratio of r:1;
and
a second pair of diodes having positive nodes coupled to each other, said second pair of diodes having negative nodes coupled to emitters of said second differential pair of transistors, said second pair of diodes having a diode area ratio of 1:r.

1 more element

A transconductance circuit, comprising:

a first and a second differential transistor having approximately equal transistors areas, said first and second differential transistors having bases coupled to a differential input signal and having collectors coupled to a load, said first and second differential transistors providing a differential current output signal;
a first pair of diodes having positive nodes coupled to each other, said first pair of diodes further having negative nodes coupled to emitters of said first and second differential transistors, said first pair of diodes having a diode area ratio of r1:r2, and
a second pair of diodes having positive nodes coupled to each other, said second pair of diodes further having negative nodes coupled to emitters of said first and second differential transistors, said second pair of diodes having a diode area ratio of r2:r1.

Dependencies are inferred from the claim text.

Low voltage bipolar transconductor circuit with extended dynamic range

Life of this patent

Low voltage bipolar transconductor circuit with extended dynamic range

Life of this patent

Abstract

Claims14