DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Information Disclosure Statement
The Information Disclosure Statement filed on 11/04/2024 has been acknowledged and considered by examiner.
Response to Arguments
Applicant’s arguments for the rejection of claims under 35 U.S.C. § 103 have been fully considered but are moot because the new ground of rejection does not rely on any reference(s) applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claims 1-10, 14, 16, 19, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Wuppermann (US 2006/0258319) in view of Magers (US 2021/0143817).
With regards to claim 1, Wuppermann teaches a test and measurement instrument (oscilloscope input channel; [0001]) having an integrated analog front end (attenuating-and-amplifying circuit 100; [0013]), comprising:
one or more amplifiers, the one or more amplifiers implemented on a high-speed amplifier integrated circuit die (amplifier 106 comprises a plurality of differential pair amplifier units 122(1)… 122(X) fabricated on a single silicon integrated circuit; [0013], [0017]; fig. 1);
a controlled-impedance signal path between an input and a reference voltage (voltage divider 104 connected between input 102 and a low voltage terminal 112; [0013]-[0014]; Fig. 1), the controlled-impedance signal path including one or more signal taps and one or more controlled-impedance attenuator stages (a string of series resistors 114 and tapping nodes 116; [0013]-[0014]; fig. 1), the one or more controlled-impedance attenuator stages implemented on the amplifier integrated circuit die (fig. 1).
Wuppermann does not teach a switching network structured to selectively couple a signal tap of the controlled-impedance signal path to a respective amplifier of the one or more amplifiers, the switching network implemented on the amplifier integrated circuit die.
However, Magers teaches a switching network structured to selectively couple a signal tap of the controlled-impedance signal path to a respective amplifier of the one or more amplifiers (a non-reflective switching circuit topology between signal paths; switching elements 302, 304, 306, 308; figs. 3A-3B; [0061]-[0063]), the switching network implemented on the amplifier integrated circuit die (implementation on integrated circuit; [0070]; fig. 8).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the amplifying circuit tapping node connections of Wuppermann to incorporate the switching network taught by Magers wherein a switching network structured to selectively couple a signal tap of the controlled-impedance signal path to a respective amplifier of the one or more amplifiers, the switching network implemented on the amplifier integrated circuit die to prevent the parasitic capacitance of the “off” paths from reflecting high frequency signals back into the transmission line and degrading the bandwidth of the oscilloscope front end ([0040]-[0042] Magers).
With regards to claim 2, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches further comprising a multiplexer (only the selected amplifier unit is activated to conduct current to the output while the non-selected amplifier units are deactivated; [0019]) having inputs coupled to the outputs of the one or more amplifiers and structured to output an amplified signal from a selected amplifier of the one or more amplifiers (the outputs of the plurality of switchable amplifier units 122(1)…122(X) are wired together to a common signal path 126 and a shared output resister 118; [0017]; fig. 1).
With regards to claim 3, Wuppermann as modified teaches the test and measurement instrument of claim 2. Wuppermann further teaches wherein the multiplexer is implemented on the amplifier integrated circuit die (the entire attenuating-and-amplifying circuit 100, including the common signal path 126 and load resistors 118 is fabricated on a single silicon IC; [0013]; fig. 1).
With regards to claim 4, Wuppermann as modified teaches the test and measurement instrument of claim 2. Wuppermann further teaches further comprising a controller (bipolar transistor 240) structured to control operation of the switching network and the multiplexer (control signals are applied to the base of bipolar transistor 240 of the switchable current source 138 to selectively activate/deactivate the units; [0025]).
With regards to claim 5, Wuppermann as modified teaches the test and measurement instrument of claim 4. Wuppermann further teaches in which the controller is configured to turn off power to non-selected amplifiers of the one or more amplifiers (deactivated differential pair amplifier units do not conduct current due to the current source 138 being turned off via the control signal; [0019], [0022]).
With regards to claim 6, Wuppermann as modified teaches the test and measurement instrument of claim 1. Magers further teaches wherein the switching network comprises a switching circuit associated with each amplifier of the one or more amplifiers, the switching circuit comprising a PIN diode (the switching network used to selectively couple the high-frequency signal paths comprises PIN diodes; [0003], [0038]).
With regards to claim 7, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches wherein each amplifier of the one or more amplifiers has a different gain (the switchable current sources 138 can be configured and operated to conduct different amounts of current; [0023]).
With regards to claim 8, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches wherein at least one of the one or more amplifiers has a predetermined gain (the amplification is determined by the fixed components of the differential pair amplifier units; [0019]-[0020]).
With regards to claim 9, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches wherein at least one of the one or more amplifiers has a programmable gain (the overall gain of the circuit is adjustable/programmable by selectively activating and deactivating different combinations of the differential pair amplifier units; [0019]).
With regards to claim 10, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches wherein each attenuator stage of the one or more attenuator stages has a different attenuation factor (because the tapping nodes 116(1)…116(N) are positioned at different locations along the series resistors, each tapping node provides a different voltage divider ratio depending on the voltage drop; [0016]).
With regards to claim 14, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches wherein a first signal tap is connected to the controlled-impedance signal path between the input and a first attenuator stage to selectively couple an unattenuated input signal to a respective first amplifier (tapping node 116(1) is positioned between the resistor 114(1) and the input 102 to provide the lowest divider ratio (unattenuated signal); [0015]-[0016]; fig. 1).
With regards to claim 16, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches wherein the reference voltage is ground (the low voltage terminal 112 is ground; [0014]).
With regards to claim 19, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann further teaches wherein the test and measurement instrument comprises an oscilloscope ([0001], [0014]).
With regards to claim 20, Wuppermann teaches an integrated circuit providing an analog front end for an oscilloscope (attenuating-and-amplifying circuit 100; [0001], [0013]), comprising:
one or more amplifiers (amplifier 106 comprises a plurality of differential pair amplifier units 122(1)… 122(X) fabricated on a single silicon integrated circuit; [0013], [0017]; fig. 1);
a controlled-impedance signal path between an input and a reference voltage (voltage divider 104 connected between input 102 and a low voltage terminal 112; [0013]-[0014]; Fig. 1), the controlled-impedance signal path including one or more signal taps and one or more controlled-impedance attenuator stages (a string of series resistors 114 and tapping nodes 116; [0013]-[0014]; fig. 1).
Wuppermann does not teach a switching network structured to selectively couple a signal tap of the controlled-impedance signal path to a respective amplifier of the one or more amplifiers.
However, Magers teaches a switching network structured to selectively couple a signal tap of the controlled-impedance signal path to a respective amplifier of the one or more amplifiers (a non-reflective switching circuit topology between signal paths; switching elements 302, 304, 306, 308; figs. 3A-3B; [0061]-[0063]).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the amplifying circuit tapping node connections of Wuppermann to incorporate the switching network taught by Magers wherein a switching network structured to selectively couple a signal tap of the controlled-impedance signal path to a respective amplifier of the one or more amplifiers to prevent the parasitic capacitance of the “off” paths from reflecting high frequency signals back into the transmission line and degrading the bandwidth of the oscilloscope front end ([0040]-[0042] Magers).
Claims 11, 12, and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Wuppermann (US 2006/0258319) in view of Magers (US 2021/0143817) and further in view of Pollock et al. (hereinafter, “Pollock”; US 7402991).
With regards to claim 11, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann as modified does not teach wherein the one or more attenuator stages comprise multiple progressive attenuation stages each having progressively lower impedances.
However, Pollock teaches wherein the one or more attenuator stages comprise multiple progressive attenuation stages each having progressively lower impedances (a wide bandwidth input attenuation circuit where the signal moves from a high-impedance probing tip (R1) through a controlled impedance transmission line (32) to a "termination resistive element (RT)"; FIG. 3; Col. 3, line 56 - Col. 4, line 9; and the resistive values of the series components (RA) are "at least an order of magnitude higher" than the resistive values of the termination stage (RT); Col. 4, lines 23-25).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the attenuator stages of Wuppermann as modified by incorporating the teachings of Pollock wherein the one or more attenuator stages comprise multiple progressive attenuation stages each having progressively lower impedances to ensure that the RC time constant at the final termination (RT) is minimized, thereby reducing interconnect parasitics and maintain high frequency response (Col. 1, lines 33-35; Pollock).
With regards to claim 12, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann as modified does not teach wherein the one or more attenuator stages are structured to have less attenuation at higher frequencies.
However, Pollock teaches wherein the one or more attenuator stages are structured to have less attenuation at higher frequencies (while DC/low-frequency signals are attenuated by resistive pairs (RA, RB), as frequency increases, the "capacitive reactance of CA and CB decreases" causing the signal to bypass the resistors; Col. 5, lines 16-19. This creates a frequency dependent impedance where the attenuation factor of the RC network is lower at higher frequencies than its attenuation factor at DC).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the attenuator stages of Wuppermann as modified by incorporating the teachings of Pollock wherein the one or more attenuator stages are structured to have less attenuation at higher frequencies to allow the attenuator to counteract high-frequency roll-off and "extend the bandwidth" (Col. 5, lines 3-6; Pollock).
With regards to claim 17, Wuppermann as modified teaches the test and measurement instrument of claim 16. Wuppermann as modified does not teach wherein the controlled-impedance signal path includes a termination resistor to ground.
However, Pollock teaches wherein the controlled-impedance signal path includes a termination resistor to ground (the resistive termination elements RTP and -RTN are coupled to ground; Col. 5, lines 57-58).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the controlled-impedance signal path of Wuppermann as modified to incorporate a termination resistor to ground at the end of the path as taught by Pollock to improve the high speed termination design, allowing termination on an integrated circuit implementation of the design (Col. 7, lines 56-59; Pollock).
Claims 13 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Wuppermann (US 2006/0258319) in view of Magers (US 2021/0143817) and further in view of Cao (US 2007/0025435).
With regards to claim 13, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann as modified does not teach wherein the controlled-impedance signal path includes one or more continuous time linear equalizers (CTLEs).
However, Cao teaches wherein the controlled-impedance signal path includes one or more continuous time linear equalizers (CTLEs) (integrated C3MOS wideband data amplifier/equalizer circuit stage which utilizes a switchable RC network 332 connected between the sources of the differential input transistors to act as a CTLE; [0055]; fig. 8A).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the differential amplifiers of Wuppermann as modified to incorporate the wideband data amplifier circuit stage taught by Cao to counteract high-frequency roll-off and inter-symbol interference in the data path thereby extending the bandwidth of the oscilloscope AFE ([0032]; Cao).
With regards to claim 15, Wuppermann as modified teaches the test and measurement instrument of claim 1. Wuppermann as modified does not teach wherein the controlled-impedance signal path includes an inductive peaking circuit at each signal tap.
However, Cao teaches wherein the controlled-impedance signal path includes an inductive peaking circuit at each signal tap (placing series input impedances 321, 322 composed only of series connected inductors directly at the inputs of the differential transistor pair; [0039]; fig.3).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the controlled-impedance signal path of Wuppermann as modified to incorporate the series inductive peaking circuits of Cao wherein the controlled-impedance signal path includes an inductive peaking circuit at each signal tap to extend the bandwidth of the amplifier and improve the input reflection ([0036]; Cao).
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Wuppermann (US 2006/0258319) in view of Magers (US 2021/0143817) and further in view of Gilbert (US 2013/0241653).
With regards to claim 18, Wuppermann as modified teaches the test and measurement instrument of claim 1. While Wuppermann as modified teaches terminating the reference voltage to ground, Wuppermann as modified does not teach wherein the amplifier integrated circuit die includes a pin structured to receive a programmable termination voltage as the reference voltage.
However, Gilbert teaches wherein the amplifier integrated circuit die includes a pin structured to receive a programmable termination voltage as the reference voltage (a “slideback feature” implemented by applying a digital word to a DAC to inject a programmable offset/centering signal to a reference node; [0027]).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the amplifying circuit of Wuppermann to incorporate the programmable reference voltage pin taught by Gilbert to enable the user to center the signal or view fine levels of detail in small signals that are riding on top of larger DC signal levels thereby improving the dynamic range and measuring capability of the oscilloscope AFE ([0027] Gilbert).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to OSAMAH MURSHED whose telephone number is (571)272-9534. The examiner can normally be reached Monday - Friday, 11 a.m. 8 p.m. ET..
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/OSAMAH MURSHED/ Examiner, Art Unit 2858
/JUDY NGUYEN/ Supervisory Patent Examiner, Art Unit 2858
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