1. A device comprising:
an amplifier stage comprising a differential pair, the differential pair having a common node;
a source follower having an input terminal and an output terminal, the output terminal of the source follower coupled to an input terminal of the amplifier stage and an output terminal of the device, the input terminal of the source follower connected to the common node of the differential pair;
a resistive device having a first terminal electrically coupled to the output terminal of the device; and
a transistor electrically coupled to a second terminal of the resistive device and the amplifier stage.
2. The device of claim 1, wherein the amplifier stage includes:
a current source electrically coupled to the differential pair; and
an active load electrically coupled to the differential pair.
3. The device of claim 2, wherein:
the input terminal of the source follower is electrically coupled to a drain electrode of a first transistor of the differential pair.
4. The device of claim 2, wherein the differential pair includes:
a first P-type metal-oxide-semiconductor (PMOS) transistor having:
a source electrode electrically coupled to the current source; and
a drain electrode electrically coupled to the active load; and
a second PMOS transistor having:
a source electrode electrically coupled to the current source;
a drain electrode electrically coupled to the active load; and
a gate electrode electrically coupled to the output terminal of the source follower.
5. The device of claim 2, wherein the active load includes:
a first N-type metal-oxide-semiconductor (NMOS) transistor having:
a drain electrode electrically coupled to the differential pair; and
a second NMOS transistor having:
a drain electrode electrically coupled to the differential pair; and
a gate electrode electrically coupled to a gate electrode of the first NMOS transistor and the drain electrode of the second NMOS transistor.
6. The device of claim 5, wherein gate-aspect ratio of the source follower is greater than gate-aspect ratio of the first NMOS transistor.
7. The device of claim 1, wherein the source follower is sized to operate in a linear region.
8. A device comprising:
a first transistor;
a second transistor having:
a source electrode electrically coupled to a source electrode of the first transistor;
a third transistor having:
a drain electrode electrically coupled to a drain electrode of the first transistor;
a fourth transistor having:
a gate electrode electrically coupled to a gate electrode of the third transistor; and
a drain electrode electrically coupled to a drain electrode of the second transistor and the gate electrode of the fourth transistor;
a fifth transistor having:
a gate electrode electrically coupled to the drain electrode of the first transistor; and
a drain electrode electrically coupled to a gate electrode of the second transistor;
a sixth transistor having:
a gate electrode electrically coupled to the source electrode of the first transistor; and
a resistive device having:
a first terminal electrically coupled to a source electrode of the sixth transistor; and
a second terminal electrically coupled to the gate electrode of the second transistor.
9. The device of claim 8, wherein gate-aspect ratio of the sixth transistor is greater than gate-aspect ratio of the third transistor.
10. The device of claim 8, wherein gate-aspect ratio of the sixth transistor is greater than gate-aspect ratio of the first transistor.
11. The device of claim 8, wherein:
the first and second transistors are P-type transistors; and
the third, fourth, fifth, and sixth transistors are N-type transistors.
12. The device of claim 8, further comprising:
a second resistive device having:
a first terminal electrically coupled to a source electrode of the fifth transistor; and
a second terminal electrically coupled to a voltage supply node.
13. The device of claim 8, further comprising:
a seventh transistor having:
a drain electrode electrically coupled to the source electrode of the first transistor.
14. The device of claim 8, wherein:
the fifth transistor is sized to operate in a linear region.
15. A method comprising:
receiving an input voltage by a first input terminal of an amplifier stage;
generating an intermediate voltage at a common node of a differential pair of the amplifier stage by amplifying the input voltage by the amplifier stage; and
generating an output voltage having a substantially same voltage as the input voltage at a second input terminal of the amplifier stage by a source follower electrically coupled to the common node and the second input terminal.
16. The method of claim 15, further including:
receiving the input voltage by a gate electrode of a first transistor of the differential pair of the amplifier stage.
17. The method of claim 16, further including:
generating the intermediate voltage at a drain electrode of the first transistor.
18. The method of claim 17, further including:
generating the output voltage by a transistor electrically coupled to the amplifier stage, and a resistive device electrically coupled to the transistor and the second input terminal.
19. The method of claim 18, further including:
maintaining a first voltage difference across the first transistor that is a substantially same voltage as a sum of a second voltage difference across the transistor and a third voltage difference across the resistive device.
20. The method of claim 15, further including:
operating the source follower in a linear region.
21. The device of claim 1, wherein the device is suitably configured, when powered, to have a first voltage at the input terminal of the source follower and a second voltage at the common node of the differential pair, the first voltage and the second voltage comprising a same voltage.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An apparatus, comprising:
a means for generating a large plurality of interspersed output light sources from an input light beam of wavelength \u03bb, at least some of the large plurality of interspersed output light sources having a first one of at least two phases fixed with respect to the phases of each other of the large plurality of interspersed output light sources, and at least some of the large plurality of interspersed output light sources having a second one of the at least two phases; and
a controller for separately controlling the amplitude of each of the large plurality of interspersed fixed phase output light sources;
wherein the large plurality of interspersed output light sources produce a large plurality of diffracting output light beams which combine to form an output light beam having amplitudes of real and imaginary parts of the output light beam controlled by the controller in a spatial and time resolved manner over the cross section of the output light beam;
wherein the controller for separately controlling the amplitude of each of the large plurality of interspersed output light beams is an array of micromirrors; and
wherein each reflecting surface of each of the micromirrors in a first state is coplanar with either a first plane or a second plane, the first and the second plane spaced a distance apart of approximately \u03bb8;
wherein the reflecting surfaces of each micromirror in the first state in one of the two planes are arranged randomly or pseudorandomly in an array.
2. An apparatus, comprising:
a means for generating a large plurality of interspersed output light sources from an input light beam of wavelength \u03bb, at least some of the large plurality of interspersed output light sources having a first one of at least two phases fixed with respect to the phases of each other of the large plurality of interspersed output light sources, and at least some of the large plurality of interspersed output light sources having a second one of the at least two phases; and
a controller for separately controlling the amplitude of each of the large plurality of interspersed fixed phase output light sources;
wherein the large plurality of interspersed output light sources produce a large plurality of diffracting output light beams which combine to form an output light beam having amplitudes of real and imaginary parts of the output light beam controlled by the controller in a spatial and time resolved manner over the cross section of the output light beam; and
wherein the controller for separately controlling the amplitude of each of the large plurality of interspersed output light beams is an array of micromirrors;
wherein a patterned layer of transparent material is applied adjacent the array of micromirrors,
wherein the patterned layer is patterned to provide one of at least two phase delays for light proceeding to and thence reflected from each micromirror, wherein the phase delays for each micromirror are fixed with respect to the phase delays of each other micromirror.
3. An apparatus, comprising:
a means for generating a large plurality of interspersed output light sources from an input light beam of wavelength \u03bb, at least some of the large plurality of interspersed output light sources having a first one of at least two phases fixed with respect to the phases of each other of the large plurality of interspersed output light sources, and at least some of the large plurality of interspersed output light sources having a second one of the at least two phases; and
a controller for separately controlling the amplitude of each of the large plurality of interspersed fixed phase output light sources;
wherein the large plurality of interspersed output light sources produce a large plurality of diffracting output light beams which combine to form an output light beam having amplitudes of real and imaginary parts of the output light beam controlled by the controller in a spatial and time resolved manner over the cross section of the output light beam:
wherein the controller for separately controlling the amplitude of each of the large plurality of interspersed output light beams is an array of micromirrors; and
wherein the controller for separately controlling and the means for generating are separately located on at least two different devices.
4. The apparatus of claim 3, wherein the controller for separately controlling is an array of micromirrors.
5. The apparatus of claim 4, wherein a patterned layer is attached to a device separated from the array of micromirrors, and wherein the patterned layer spatially separates light incident on the patterned layer into a large plurality of interspersed output light beams, each of the interspersed output light beams having one of at least two phases fixed with respect to the phases of each of the other interspersed output light beams, and wherein an optical system focuses each of the interspersed light beams on to a separate micromirror, and wherein each micromirror modulates the amplitude of each of the interspersed light beams reflected from the micromirror.
6. The apparatus of claim 5, wherein the patterned layer spatially separates light incident on the patterned layer into a large plurality of interspersed light beams, each of the interspersed light beams having one of four phases fixed with respect to the phases of each of the other interspersed light beams, the four phases differing in phase by one of approximately 90\xb0, 180\xb0 or 270\xb0.
7. The apparatus of claim 4, wherein a patterned layer is attached to a device separated from the array of micromirrors, and wherein each micromirror modulates the amplitude of each interspersed output light beam reflected from the micromirror, and wherein an optical system focuses each of the interspersed output light beams on tothe patterned layer, wherein the interspersed light beams have phases controlled by the patterned layer so that each of the interspersed light beams has one of at least two phases fixed with respect to the phases of each of the other interspersed light beams.
8. The apparatus of claim 7, wherein the patterned layer spatially separates light incident on the patterned layer into a large plurality of interspersed output light beams, each of the interspersed output light beams having one of four phases fixed with respect to the phases of each of the other interspersed output light beams, the four phases differing in phase by one of approximately 90\xb0, 180\xb0 or 270\xb0.
9. An apparatus, comprising:
an array of separately controllable micromirrors for separately controlling the amplitude of real and imaginary parts of a diffracted output light beam of wavelength \u03bb, wherein approximately equal numbers of micromirrors of the array have a reflecting surface in a first state coplanar with one of four parallel planes, the four parallel planes spaced a distance approximately \u03bb8 apart,
wherein the reflecting surfaces of each micromirror in the first state in one of the two planes are arranged randomly or pseudorandomly in an array.
10. The apparatus of claim 9, wherein the separately controlled amplitude is either zero or one.