# US 7,612,568 B2 · Open-circuit testing system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,612,568 B2 - Document ID: US7612568B2 - Status: Granted - Kind: B2 - Application number: 11/743,641 - Filed: 2007-05-02 - Published: 2008-09-11 - Granted: 2009-11-03 - Earliest claimed: 2007-03-08 - Assignees: Test Research, Inc. - Inventors: Chien-Wei Chen; Chia-Ming Chen - Web page: https://patentgrep.com/patent/US7612568B2 ## CPC - G01R 31/70: Testing of connections between components and printed circuit boards (G01R31/68 takes precedence) - G01R 31/304: of printed or hybrid circuits (G01R31/305 - G01R31/315 take precedence) - G01R 31/312: by capacitive methods - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract The invention discloses a testing system and method suitable for determining the connection state of an electronic component in an electronic device assembly. In an embodiment, the testing system comprises a signal sensing unit configured to provide a sensed signal induced by capacitive coupling in response to the output of a testing signal passing through a tested pin, a signal processor unit configured to filter and over-sample the sensed signal to obtain a digital signal, and an analyzer unit configured to compute the digital signal for determining a connection state of the test pin. ## Claims ### Claim 1 A testing method for determining a connection state of an electronic component in an electronic device assembly, the method comprising: obtaining a sensed signal induced by capacitive coupling in response to the output of a testing signal passing through a tested pin of the electronic component; applying a signal processing sequence on the sensed signal, the processing sequence including: filtering and over-sampling the sensed signal to obtain a digital signal; and applying a validation test on the digital signal to determine whether the sensed signal is an acceptable measure, wherein the validation test is applied by computing the digital signal to determine a correspondence with a predetermined capacitive coupling reference; when a result of the validation test finds no correspondence with the predetermined capacitive coupling reference from the digital signal, raising a frequency and/or amplitude of the testing signal; when a correspondence with the predetermined capacitive coupling reference is found, converting the digital signal into frequency-domain spectrum data; and determining the connection state of the tested pin based on the frequency-domain spectrum data. ### Claim 2 (depends on 1) The method according to claim 1, wherein the signal processing sequence includes amplifying the sensed signal before filtering the sensed signal. ### Claim 3 (depends on 1) The method according to claim 1, wherein the signal processing sequence includes processing the sensed signal through an anti-alias filter before over-sampling the sensed signal. ### Claim 4 (depends on 1) The method according to claim 1, wherein the signal processing sequence includes processing the digital signal through a digital filter after over-sampling the sensed signal. ### Claim 5 (depends on 4) The method according to claim 4, wherein the digital filter includes a finite impulse response filter. ### Claim 6 (depends on 1) The method according to claim 1, further comprising: obtaining a new sensed signal corresponding to the testing signal of raised frequency and/or amplitude; and applying the signal processing sequence for the new sensed signal. ### Claim 7 (depends on 1) The method according to claim 1, wherein converting the digital signal into frequency-domain spectrum data includes applying a Fast Fourier Transform to convert the digital signal into a frequency-domain spectrum data, and determining the connection state of the tested pin includes comparing the frequency-domain spectrum data against a range of reference values. ### Claim 8 A testing system suitable for determining a connection state of an electronic component in an electronic device assembly, the testing system comprising: a signal sensing unit providing a sensed signal induced by capacitive coupling in response to the output of a testing signal passing through a tested pin of the electronic component; a signal processor unit filtering and over-sampling the sensed signal to obtain a digital signal; an analyzer unit applying a processing sequence on the sensed signal, wherein the processing sequence comprises: determining whether the sensed signal is an acceptable measure by computing the digital signal to determine a correspondence with a predetermined capacitive coupling reference; and when a correspondence with the predetermined capacitive coupling reference is found, computing frequency-domain spectrum data from the digital signal for determining a connection state of the tested pin; and a controller raising a frequency and/or amplitude of the testing signal when no correspondence with the predetermined capacitive coupling reference is found from the digital signal. ### Claim 9 (depends on 8) The system according to claim 8, wherein the signal processor unit includes an anti-alias filter through which the sensed signal is processed before being over-sampled. ### Claim 10 (depends on 8) The system according to claim 8, wherein the signal processor unit includes a digital filter through which the digital signal is processed before being converted into frequency-domain spectrum data. ### Claim 11 (depends on 10) The system according to claim 10, wherein the digital filter includes a finite impulse response filter. ### Claim 12 (depends on 8) The system according to claim 8, wherein the analyzer unit applies a Fast Fourier Transform to convert the digital signal into frequency-domain spectrum data, and compares the frequency-domain spectrum data against a range of reference values for determining the connection state of the tested pin. ### Claim 13 (depends on 8) The system according to claim 8, wherein the testing signal has a frequency of about 100 kHz or higher.