Election/Restrictions
Applicant’s election without traverse of Invention I in the reply filed on 10/21/2025 is acknowledged.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1-3, 10-13, 22 is/are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Challa et al. (US 10,411,600).
Regarding claims 1, 22, Challa et al., figs. 1, 2, 3, discloses a current-steering circuit, comprising: a first current load that is a light emitter (see the configurable load 110 includes a first load portion 115 (for example, comprising three LEDs LED1, LED2, LED3)); a second current load (see a second load portion 117 (for example, comprising two LEDs LED4, LED5)); a current source or current sink (current steering gate driver 130); and a current-steering switch (current steering gate driver 140), wherein the current-steering switch is operable to connect the first current load (CT) to the current source or current sink in a first switch mode (120) and is operable to connect the second current load (130) to the current source or current sink in a second switch mode (122) different from the first switch mode (The current steering control circuit 130 further includes current steering amplifiers 220a, 220b each having, respectively, an input 221a, 221b coupled to receive the feedback voltage dv/dt through a negative feedback element 230 and an output 222a, 222b coupled to the control terminal 122c of the switch 122. The gain of the current steering amplifiers 220a, 220b is set to be constant, and the value of resistor R1 can be changed to modify the slew rate of the switch 122. The gain of the current steering amplifiers 220a, 220b are selected such that, with maximum adjustable slew rate, the steered current is equal to the minimum of the gate driver source current (refer, for example, to arrow 201 of FIG. 2) or sink current (refer, for example, to arrow 202 of FIG. 2).
Regarding claim 2, Challa et al., figs. 1, 2, 3, discloses the current-steering circuit of claim 1, wherein the second current load is a non-light-emissive load (FIG. 3 is a schematic of a portion of the circuit of FIG. 1 including a current steering gate driver 140 coupled to the Buck-Boost switch 120, with the current steering gate driver circuit 140 shown in greater detail. It will be appreciated in light of the present disclosure that the gate driver 140 can have the same structure as gate driver 130 (see FIG. 2) and differ in their connections to the switch that they control. In some embodiments, current steering gate driver 140 may have a different structure than current steering gate driver 130 and/or may respond to a different feedback voltage dv/dt to achieve a different slew rate for the switch that the driver controls).
Regarding claim 3, Challa et al., figs. 1, 2, 3, discloses the current-steering circuit of claim 1, wherein the light emitter is a first light emitter and the second current load is a second light emitter (The configurable load 110 includes a first load portion 115 (for example, comprising three LEDs LED1, LED2, LED3) and a second load portion 117 (for example, comprising two LEDs LED4, LED5) coupled together at an intermediate node CT of the load 110).
Regarding claim 10, Challa et al., figs. 1, 2, 3, discloses the current-steering circuit of claim 1, wherein the current source or current sink is a constant-current source or constant-current sink (regulator 105 is controlled by the output 154 of driver 152 so as to adjust the output voltage VOUT 108 as necessary to maintain a substantially constant load current iLED 107 to the load 110).
Regarding claim 11, Challa et al., figs. 1, 2, 3, discloses, discloses the current-steering circuit of claim 1, wherein the constant-current source or constant-current sink is constructed such that current provided thereby is a current selected to optimize efficiency of light emission from the light emitter (regulator 105 is controlled by the output 154 of driver 152 so as to adjust the output voltage VOUT 108 as necessary to maintain a substantially constant load current iLED 107 to the load 110) (The gain of the current steering amplifiers 320a, 320b is set to be constant, and the value of resistor R1 can be changed to modify the slew rate of the switch 120).
Regarding claim 12, Challa et al., figs. 1, 2, 3, discloses, discloses the current-steering circuit of claim 1, wherein the current-steering switch comprises a current-steering transistor connected to each current load to control flow of current through the current load, the current-steering transistor responsive to a switch-control signal (see figs. 1, 3, 5, A control terminal 120c of the switch 120 is coupled to receive a control signal from the current steering gate driver 140. The Buck-Boost switch 120 can be a P-Type Metal-Oxide-Semiconductor Field Effect Transistor (PMOS) device. The second, Boost switch (N2) 122 has a first terminal 122a coupled to the second load portion 117 and a second terminal 122b coupled to a reference potential (e.g., ground). A control terminal 122c of the Boost switch 122 is coupled to receive a control signal from the current steering gate driver 130. The second Boost switch 122 can be a N-Type Metal-Oxide-Semiconductor Field Effect Transistor (NMOS) device).
Regarding claim 13, Challa et al., figs. 1, 2, 3, discloses, discloses the current-steering circuit of claim 1, wherein the current-steering switch comprises a differential pair of transistors comprising sources and drains, wherein (i) the sources are connected in common to form a common connection and the drains form separate connections or (ii) the drains form a common connection and the sources form separate connections, wherein one of the differential pair of transistors is responsive to a positive switch-control signal and another of the differential pair of transistors is responsive to a negative version of the positive switch-control signal (The first, Buck-Boost switch (P1) 120 has a first terminal 120a coupled, through a diode D2, to the intermediate node CT of the load and a second terminal 120b coupled to the battery voltage VBAT 102. The second terminal 120b is not coupled to the second load portion 117 of the load 110. A control terminal 120c of the switch 120 is coupled to receive a control signal from the current steering gate driver 140. The Buck-Boost switch 120 can be a P-Type Metal-Oxide-Semiconductor Field Effect Transistor (PMOS) device. The second, Boost switch (N2) 122 has a first terminal 122a coupled to the second load portion 117 and a second terminal 122b coupled to a reference potential (e.g., ground). A control terminal 122c of the Boost switch 122 is coupled to receive a control signal from the current steering gate driver 130. The second Boost switch 122 can be a N-Type Metal-Oxide-Semiconductor Field Effect Transistor (NMOS) device).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 4, 5, is/are rejected under 35 U.S.C. 103 as being unpatentable over Challa et al. (US 10,411,600) in view of Kadwell et al. (US 7616126).
Regarding claims 4, 5, Challa et al., figs. 1, 2, 3, discloses, discloses the current-steering circuit of claim 1.
However, Challa et al. is silent about the frequency of the emitters.
Kadwell et al. (US 7616126)., discloses capture modulated light sources an analyze their frequencies an upper limit may be set on the capture time, for instance 0.5 sec, or 1 sec. to save power and, or, minimize erroneous readings from lights which may be manually switched on or off during the sample period. The optical transducer's signal may be processed by a microprocessor or by discrete components to find the frequency, if any, ambient light is modulated. Once the frequency is known the delay between a reference reading and an actual reading can be adjusted to allow the optical transducer to take readings which correspond to significantly identical phase angles on the modulated wave. In this manner variable frequency light sources can be compensated for.the case where light is modulated at a different frequency than that of the power to the particle sensor having only 2 readings may not be optimum for noise compensation.
It would have been obvious to the skilled in the art before the effective filing date of the invention to provide the second light emitter emits light that has a different frequency from light emitted by the first light emitter, and/or the second light emitter emits light that is not visible to a human visual system, in Challa et al., as suggested by Kadwell et al.., the motivation in order to lower manufacturing costs by eliminating separate component.
Claim(s) 21 is/are rejected under 35 U.S.C. 103 as being unpatentable over Challa et al. (US 10,411,600) in view of Lee et al. (US 2018/0049283).
Regarding claim 21, Challa et al., figs. 1, 2, 3, discloses, discloses the current-steering circuit of claim 1.
However, Challa et al. is silent about the current-steering display is a high-frame-rate display having a frame rate no less than 600 Hz.
Lee et al. (US 2018/0049283), discloses some LED applications require the ability to dim the LEDs. With one type of LED dimming, sometimes referred to as PWM dimming, the intensity of the LEDs is adjusted by turning the LEDs off and on in response to a PWM signal at a variable duty cycle proportional to the desired brightness and with a fixed DC current and frequency (typically 100 Hz to 1 KHz).
It would have been obvious to the skilled in the art before the effective filing date of the invention to provide the current-steering display is a high-frame-rate display having a frame rate no less than 600 Hz, in Challa et al., as suggested by Lee et al. (US 2018/0049283), in order the motivation to PWM signal may be provided to the LED driver from an external source or may be internally generated.
Allowable Subject Matter
Claims 6, 14, 15 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
None of the references cited in record disclose or suggest the current-steering circuit of claim 1, wherein the current source or current sink is a current source and the current-steering switch is operable to switch current from the current source at a frequency no less than 1 MHz or the current source or current sink is a current sink and the current-steering switch is operable to switch current to the current sink at a frequency no less than 1 MHz; and/or the current-steering circuit of claim 1, wherein the current-steering switch is responsive to a multi-bit switch-control signal comprising control bits, wherein the current-steering switch comprises successive levels of differential pairs of transistors, each successive level controlled by a different one of the control bits to provide the switch-control signal, wherein a final level of the successive levels controls current flow through the first current load and the second current load.
Claim 15 falls with parent claim.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Van N Chow whose telephone number is (571)272-7590. The examiner can normally be reached M-F 10-6PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Xiao Ke can be reached at 5712727776. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/VAN N CHOW/Primary Examiner, Art Unit 2627