US 6,586,996 B2Granted

Method and system for producing a drive signal for a current steering amplifier

AssigneeBroadcom Corporation

InventorsAdel Fanous, Leonard Dauphinee, Lawrence M. Burns, Donald McMullin

Life of this patent

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Abstract

Provided is a method and system for producing a drive signal for a current steering amplifier. An exemplary method comprises receiving a supply voltage signal and a differential input signal as a circuit input. A differential amplifier drive signal is produced in response to the received supply voltage signal, the received differential input signal, and the received differential control signal. The received differential input signal is adjusted to a value where magnitudes of negative and positive components of the differential control signal become equal to one another and are within a predetermined amount of a magnitude of the supply voltage signal.

Claims10

Dependent claims

A method for providing a drive signal for an amplification circuit configured to operate based upon a received differential control signal, the method using a signal generating circuit including:

a first circuit portion configured to receive a supply voltage signal and including a first differential transistor pair, the first differential transistor pair including (i) inverting and non-inverting differential input ports configured to receive a differential input signal and (ii) first and second pairs of differential output ports configured to respectively produce first and second differential output signals, the first and second differential output signals being responsive to the differential input signal and the supply voltage signal, the first differential output signal having a first voltage magnitude and the second differential output signal having a second voltage magnitude, wherein the first and second voltage levels are offset from one another;
and
a second circuit portion including second and third differential transistor pairs, each second and third differential pair (i) being configured to receive the supply voltage signal and (ii) having first and second differential input ports;
wherein the first differential input port of the second differential pair and the second differential input port of the second differential pair is configured to receive the first differential output signal, and the second differential input port of the third differential pair and the first differential input port of the third differential pair is configured to receive the second differential output signal;
and
wherein the second circuit portion produces a differential amplifier drive signal responsive to the received first and second differential output signals and to the supply voltage signal,
the method comprising:
receiving the supply voltage signal;
receiving the differential input signal;
producing the differential amplifier drive signal in response to the received supply voltage signal, the received differential input signal, and the received differential control signal;
and
adjusting the received differential input signal to a value where magnitudes of negative and positive components of the differential control signal (i) become equal to one another and (ii) are within a predetermined amount of a magnitude of the supply voltage signal.

9 more elements

An apparatus comprising:

first and second active devices having common terminals coupled together and control terminals respectively forming first and second differential input ports, the first and second differential input ports being configured to receive a differential input signal;
first and second impedance devices, the first impedance device having a first terminal coupled to an output terminal of the first active device to form a first coupling node and the second impedance device having a first terminal coupled to an output terminal of the second active device to form a second coupling node, the first and second coupling nodes respectively forming first and second differential output ports;
and
third and fourth impedance devices, the third impedance device having a first terminal coupled to a second terminal of the first impedance device to form a third coupling node and the fourth impedance device having a first terminal coupled to a second terminal of the second impedance device to form a fourth coupling node, the third and fourth coupling nodes respectively forming third and fourth differential output ports, second terminals of the third and fourth impedance devices being configured for receiving a supply voltage signal;
wherein the first and second differential output ports are configured to produce a first differential output signal having a first voltage level, the first differential output signal being responsive to the differential input signal and the supply voltage signal;
wherein the third and fourth output terminals are configured to produce a second differential output signal having a second voltage level, the second differential output signal being responsive to the differential input signal and the supply voltage signal;
and
wherein the first and second voltage levels are offset.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/214,091Filed 8 Aug 2002 · us provisional application
Priority: 15 Aug 2001
Published: US 2003/0034842 A120 Feb 2003
Granted: 1 Jul 2003
Term ends: Not estimatedThe source records don’t support an estimate.

Classification16 codes

H03F 3/45183
Using MOSFET transistors as the active amplifying circuit: long tailed pairs
H03F 3/45201
Pl types: non-folded cascode stages
H03F 3/45475
Characterised by the way of implementation of the active amplifying circuit in the differential amplifier: using IC blocks as the active…
H03G 1/0029
The device being at least one of the amplifying solid-state elements: using field-effect transistors [FET]