Processing

Please wait...

Settings

Settings

Goto Application

1. WO2020200480 - SAR ADC WITH ALTERNATING LOW AND HIGH PRECISION COMPARATORS AND UNEVEN ALLOCATION OF REDUNDANCY


Disclaimer The image version (PDF) available on PATENTSCOPE is the official version. This online html version is provided to assist users. Despite the great care taken in its compilation to ensure a precise and accurate representation of the data appearing on the printed document/images, errors and/or omissions cannot be excluded due to the data transmittal, conversion and inherent limitations of the (optional) machine translation processes used. Hyperlinks followed by this symbol , are to external resources that are not controlled by WIPO. WIPO disclaims all liability regarding the above points.

WRITTEN OPTION OF THE INTERNATIONAL SEARCHING AUTHORITY
International application No. Applicant's or agent's file reference
PCT/EP2019/058701 P76140 WO1
International filing date (day/month/year) Priority date (day/month/year) Date of mailing (day/month/year)
05 April 2019 02 January 2020
International Patent Classification (IPC) or both national classification and IPC
     H03M 1/46 (2006.01)i; H03M 1/06 (2006.01)i; H03M 1/12 (2006.01)i
Applicant TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
1. This opinion contains indications relating to the following items:
Box No. I Basis of the opinion
Box No. II Priority
Box No. III Non-establishment of opinion with regard to novelty, inventive step and industrial applicability
Box No. IV Lack of unity of invention
Box No. V Reasoned statement under Rule 43bis.1(a)(i) with regard to novelty, inventive step and industrial applicability; citations and explanations supporting such statement
Box No. VI Certain documents cited
Box No. VII Certain defects in the international application
Box No. VIII Certain observations on the international application
2. FOR FURTHER ACTION
If a demand for international preliminary examination is made, this opinion will be considered to be a written opinion of the International Preliminary Examining Authority (“IPEA”) except that this does not apply where the applicant chooses an Authority other than this one to be the IPEA and the chosen IPEA has notified the International Bureau under Rule 66.1 bis(b) that written opinions of this International Searching Authority will not be so considered.
If this opinion is, as provided above, considered to be a written opinion of the IPEA, the applicant is invited to submit to the IPEA a written reply together, where appropriate, with amendments, before the expiration of 3 months from the date of mailing of Form PCT/ISA/220 or before the expiration of 22 months from the priority date, whichever expires later.
For further options, see Form PCT/ISA/220.
Box No. I Basis of the opinion
1. With regard to the language, this opinion has been established on the basis of:
the international application in the language in which it was filed.
a translation of the international application into ___________________________ which is the language of a translation furnished for the purposes of international search (Rules 12.3(a) and 23.1(b)).
2.
This opinion has been established taking into account the rectification of an obvious mistake authorized by or notified to this Authority under Rule 91 (Rule 43bis.1(a)).
3. With regard to any nucleotide and/or amino acid sequence disclosed in the international application, this opinion has been established on the basis of a sequence listing:
a. forming part of the international application as filed:
in the form of an Annex C/ST.25 text file.
on paper or in the form of an image file.
b. furnished together with the international application under PCT Rule 13ter.1(a) for the purposes of international search only in the form of an Annex C/ST.25 text file.
c. furnished subsequent to the international filing date for the purposes of international search only:
in the form of an Annex C/ST.25 text file (Rule 13ter.1(a)).
on paper or in the form of an image file (Rule 13ter.1(b) and Administrative Instructions, Section 713).
4.
In addition, in the case that more than one version or copy of a sequence listing has been filed or furnished, the required statements that the information in the subsequent or additional copies is identical to that forming part of the application as filed or does not go beyond the application as filed, as appropriate, were furnished.
5. Additional comments:
Box No. V Reasoned statement under Rule 43bis.1(a)(i) with regard to novelty, inventive step and industrial applicability; citations and explanations supporting such statement
1. Statement:
Novelty (N)
Claims
2, 3, 5-12, 14, 15, 17-24
YES
Claims
1, 4, 13, 16
NO
Inventive step (IS)
Claims
2, 3, 5-12, 14, 15, 17-24
YES
Claims
1, 4, 13, 16
NO
Industrial applicability (IA)
Claims
1-24
YES
Claims
 
NO
2. Citations and explanations :
see separate sheet
Box No. VII Certain defects in the international application
The following defects in the form or contents of the international application have been noted:
see separate sheet
Box No. VIII Certain observations on the international application
The following observations on the clarity of the claims, description, and drawings or on the question whether the claims are fully supported by the description, are made:
see separate sheet
Continuation of:
Re Item V
Reasoned statement with regard to novelty, inventive step or industrial applicability; citations and explanations supporting such statement
Reference is made to the following documents:
D1 LIU SHAOLONG ET AL: "A 125 MS/s 10.4 ENOB 10.1 fJ/Conv-Step Multi-Comparator SAR ADC with Comparator Noise Scaling in 65nm CMOS",
ESSCIRC 2018 - IEEE 44TH EUROPEAN SOLID STATE CIRCUITS CONFERENCE (ESSCIRC), IEEE, 3 September 2018 (2018-09-03), pages 22-25, XP033420658,
DOI: 10.1109/ESSCIRC.2018.8494253
[retrieved on 2018-10-16]
D2 CHANG KWUANG-HAN ET AL: "A 12 bit 150 MS/s 1.5 mW SAR ADC with adaptive radix DAC in 40 nm CMOS",
2016 IEEE ASIAN SOLID-STATE CIRCUITS CONFERENCE (A-SSCC), IEEE, 7 November 2016 (2016-11-07), pages 157-160, XP033061284,
DOI: 10.1109/ASSCC.2016.7844159
ISBN: 978-1-5090-3699-8
[retrieved on 2017-02-06]
 
[1] Novelty
Insofar as the subject-matter of claims can be understood (see objections under section VIIIbelow), the present application does not meet the criteria of article 33(1) PCT, because the subject-matter of claims 1,4,13 and 16is not new in the sense of Article 33(2) PCT.
Document D1 discloses (see section I.C;figure 4, the references in parentheses applying to this document)
[1.1] Independent claim 1
A method of performing a Successive Approximation Register, SAR, Analog to Digital Converter, ADC, process, using a SAR ADC (figure 4) comprising a first comparator set (x4,x3), each comparator in the first comparator set having substantially a same first precision and first noise level (see the table of figure 4c listing the different comparator's parameters, first row), and a second comparator set (x2), each comparator in the second comparator set having substantially a same second precision which is greater than the first precision, and second noise level which is lower than the first noise level (table of figure 4c, second row), the method comprising, for each analog value conversion:
performing a first decision cycle using one of the first and second comparator sets (see figure 4b, last clk3 pulse) against a first range (resulting range after the first 7 SAR iterations), resulting in an indication of a first subrange (resulting range after the eight iteration) ;
[strikethrough>selecting a redundancy amount for a successive decision cycle in response to whether the first decision cycle is performed using the first or second comparator set <strikethrough](see section VIII, features found unclear cannot contribute to the assessment of novelty and inventive step) ; and
performing a second decision cycle immediately after the first decision cycle (see figure 4b, first clk3 pulse operating on x3), using the other of the first and second comparator sets (x2) against a second range (resulting range after the eight iteration) [strikethrough>greater than the first subrange by the selected redundancy amount <strikethrough](unclear as a consequence of the unclear definition of the redundancy amount, see section VIII, point 11)
[1.2] Independent claim 13
The subject-matter of independent claim13 corresponds in terms of apparatus features to that of independent claim1. Therefore the objections raised in respect of the latter also apply, mutatis mutandis, to independent claim13 which is thus not allowable under Article 33(2) PCT for lack of novelty of its subject-matter.
[1.3] D1 further discloses the subject-matter of claims 4 and 16being all the comparators of D1 single-bit comparators.
[2] Inventive step
The subject-matter of claim 2 (and correspondently claim 14), once properly clarified by including all the essential features (see section VIII) seems neither known from, nor rendered obvious by the available prior art cited in the international search report and appears to represent an alternative solution to the problem of improving the speed of a SAR converter, thus involving an inventive step (Article 33(3) PCT) for the following reasons:
[2.1] Compensating the use of a "high noise comparator" by adding redundancy is per-se known in the art (see e.g. D2, page 158, left-hand column ,second paragraph).
[2.2] However in the prior art the comparators with higher noise are always used before the low-noise comparators and there is no track of alternating noisy and less noisy comparators (in particular using a noisy comparator after a less-noisy one) while allocating more redundancy to decision cycles immediately following the use of the noisy comparators, thus allowing to mitigate the lost of redundancy margin during the SAR conversion. Even combining D1 and D2 such solution would not be reached.
[2.3] The same reasoning applies, mutatis-mutandis to the subject-matter of claim 14 that, once clarified, would be considered as new and inventive.
[2.4] Claims 3,5-12 and 15,17-24 when made dependent respectively on such clarified claims 2 and 14, would also meet the requirements of the PCT with respect to novelty and inventive step.
[2.5] It is noted that this suggestion is only for assisting the applicant in his decision on how to proceed. It in no way precludes consideration of alternative solutions submitted by the applicant. The responsibility for determining the text of the application and in particular for defining the subject-matter for which protection is sought remains with the applicant.
 
Re Item VII
Certain defects in the international application
In case the current International Application would enter the European regional phase, the following objections under the EPC are expected to be raised:
[1] The independent claims should be drafted in two-part form comprising a precharacterising and a characterising portion (Rule 43(1) EPC). The precharacterising portion should indicate the technical features which, in combination, are part of the prior art according to D1 (Rule 43(1 )(a) EPC).
[2] Documents D1-D2, which appear to represent the most relevant prior art, should be acknowledged in the description (Rule 42(1) (b) EPC).
 
Re Item VIII
Certain observations on the international application
The application does not meet the requirements of Article 6 PCT, because claims 1 and 13 are not clear.
[1] The expression of claim 1 "selecting a redundancy amount for a successive decision cycle in response to whether the first decision cycle is performed using the first or second comparator set" is unclear as it does not allow to determine how to select the redundancy amount.
[2] Moreover, it is clear from the description on page 5, lines 23-28 that, in order to compensate the use of a lower accuracy comparator, it is essential to:
allocate more redundancy to decision cycles immediately following the use of a lower accuracy/higher noise comparators (or sets)(see e.g. claim 2) .
[2.1] Furthermore the description states on page 5, lines 23-28 "Whatever the mix of comparators used in the early (MSB) decision cycles, lower noise (higher accuracy) comparators are deployed for a plurality of the last (LSB) decision cycles." as also evident from all the embodiments shown at figures 5,8,9,10,11 however no mention to LSB decision cycles is present in claim 1.
[2.2] Moreover, from the description (page 12, lines 13-15) it appears that the advantage provided by alternating noisy and less-noisy comparators respect to alternating the same kind of comparators is related to an increased speed assuming that the the noisy comparators are faster that the less-noisy comparators. Considering that a noisy comparator is not implicitly faster then a less-noisy comparator, such feature is also considered essential.
[2.3] Since independent claims 1 and 13 do not contain these features they do not meet the requirement following from Article 6 PCT taken in combination with Rule 6.3(b) PCT that any independent claim must contain all the technical features essential to the definition of the invention.
[3] Furthermore, in the expression of claim 1 "performing a second decision cycle [...]" (last three lines of claim 1), it is unclear whether "a second decision cycle" refers to "a second decision cycle" previously mentioned in the claim or it is a new decision cycles. A consistent terminology should be used.
[4] The relative term "substantially" used in claims 1 and 13 has no well-recognized meaning and leaves the reader in doubt as to the meaning of the technical features to which it refers, thereby rendering the definition of the subject-matter of said claims unclear, Article 6 PCT.
 
 
Name and mailing address of the ISA/:
European Patent Office
P.B. 5818, Patentlaan 2, 2280 HV Rijswijk,
Netherlands
Telephone No. +31 (0)70 340-2040
Facsimile No. +31 (0)70 340-3016
Date of completion of this opinion:
17 December 2019
Authorized officer:
Galardi, Leonardo
Telephone No. +31 (0)70 340-8031