# US 2018/0026624 A1 · Half-bridge driver fault diagnostic 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 2018/0026624 A1 - Document ID: US20180026624A1 - Status: Published application - Kind: A1 - Application number: 15/218,989 - Filed: 2016-07-25 - Published: 2018-01-25 - Earliest claimed: 2016-07-25 - Assignees: Continental Automotive Systems, Inc. - Applicants: Continental Automotive Systems, Inc. - Inventors: Chung Heum Baik; Jorge Gonzalez-Amaya; Mauricio Eduardo Hernandez-Distancia - Web page: https://patentgrep.com/patent/US20180026624A1 ## CPC - G01R 31/50: Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections (testing of sparking plugs H01T13/58) - G01R 31/52: Testing for short-circuits, leakage current or ground faults - H03K 17/08122: {in field-effect transistor switches} - H03K 17/687: the devices being field-effect transistors - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) ## Abstract An apparatus for controlling the application of electrical power to a load includes a controller, a controllable high side driver electrically connected to a first electrical terminal of the load, and a controllable low side driver electrically connected to a second electrical terminal of the load. The apparatus also includes a diagnostic circuit configured to sense and identify an open load fault condition, a high-side short circuit to battery fault condition, a low-side short circuit to ground fault condition, a high-side short circuit to ground fault condition, a low-side short circuit to battery fault condition, and a short circuited load fault condition. The diagnostic circuit is also configured to sense and identify a condition wherein none of the open load, high-side short circuit to battery, low-side short circuit to ground, high-side short circuit to ground, low-side short circuit to battery, and short circuited load fault conditions are present. ## Claims ### Claim 1 An apparatus for controlling the application of electrical power to a load having a first electrical terminal and a second electrical terminal, the apparatus comprising: a controller; a high side driver electrically connected to a voltage supply and to the first electrical terminal of the load, the high side driver controllable to an on state wherein current flow from the voltage supply to the load is enabled and to an off state wherein current flow from the voltage supply to the load is disabled; a low side driver electrically connected to the second electrical terminal of the load and to a ground connection, the low side driver controllable to an on state wherein current flow from the load to the ground connection is enabled and to an off state wherein current flow from the load to the ground connection is disabled; a diagnostic circuit configured to sense a fault condition and to generate a signal indicative of the fault condition; wherein the diagnostic circuit is configured to sense and identify a first fault condition wherein the first fault condition is an open load fault condition; wherein the diagnostic circuit is configured to sense and identify a second fault condition wherein the second fault condition is a high-side short circuit to battery fault condition; wherein the diagnostic circuit is configured to sense and identify a third fault condition wherein the third fault condition is a low-side short circuit to ground fault condition; wherein the diagnostic circuit is configured to sense and identify a fourth fault condition wherein the fourth fault condition is a high-side short circuit to ground fault condition; wherein the diagnostic circuit is configured to sense and identify a fifth fault condition wherein the fifth fault condition is a low-side short circuit to battery fault condition; wherein the diagnostic circuit is configured to sense and identify a sixth fault condition wherein the sixth fault condition is a short circuited load fault condition; wherein the diagnostic circuit is configured to sense and identify a condition wherein none of the first fault condition, the second fault condition, the third fault condition, the fourth fault condition, the fifth fault condition, and the sixth fault condition are present. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein, upon sensing a fault condition that results in current through the high side driver, the low side driver, and/or the load exceeding a predetermined current threshold, a first control signal is sent to control the high side driver to its off state and a second control signal is sent to control the low side driver to its off state. ### Claim 3 (depends on 2) The apparatus of claim 2 wherein the fault condition that results in current through the high side driver, the low side driver, and/or the load exceeding the predetermined current threshold is the high-side short circuit to ground fault condition, the low-side short circuit to battery fault condition, or the short circuited load fault condition. ### Claim 4 (depends on 1) The apparatus of claim 1 wherein the diagnostic circuit comprises a high-side on-state diagnostic circuit and a low-side on-state diagnostic circuit; wherein the high-side on-state diagnostic circuit is configured to monitor a current through the high side driver from the voltage supply to the first electrical terminal of the load and to generate a high-side overcurrent logic signal indicative of whether the current through the high side driver is above or below a predetermined high-side current threshold; wherein the low-side on-state diagnostic circuit is configured to monitor a current through the low side driver from the second electrical terminal of the load to the ground connection and to generate a low-side overcurrent logic signal indicative of whether the current through the low side driver is above or below a predetermined low-side current threshold; the apparatus further including a first latch configured to capture the state of the high-side overcurrent logic signal and a second latch configured to capture the state of the low-side overcurrent logic signal. ### Claim 5 (depends on 4) The apparatus of claim 4 wherein the diagnostic circuit further comprises a high-side off-state diagnostic circuit and a low-side off-state diagnostic circuit; wherein the high-side off-state diagnostic circuit comprises at least one current source configured to be connectable to the first electrical terminal of the load so as to be able to charge and/or discharge a first capacitor connected from the first electrical terminal of the load to the ground connection, and a high-side voltage comparison means configured to indicate whether the voltage at the first electrical terminal of the load is less than a high-side low voltage threshold, between the high-side low voltage threshold and a high-side high voltage threshold, or above the high-side high voltage threshold, wherein the high-side high voltage threshold is a higher voltage than the high-side low voltage threshold; wherein the low-side off-state diagnostic circuit comprises at least one current source configured to be connectable to the second electrical terminal of the load so as to be able to charge and/or discharge a second capacitor connected from the second electrical terminal of the load to the ground connection, and a low-side voltage comparison means configured to indicate whether the voltage at the second electrical terminal of the load is less than a low-side low voltage threshold, between the low-side low voltage threshold and a low-side high voltage threshold, or above the low-side high voltage threshold, wherein the low-side high voltage threshold is a higher voltage than the low-side low voltage threshold. ### Claim 6 (depends on 5) The apparatus of claim 5 further comprising a pull-up resistor connected between a reference voltage source and the first electrical terminal of the load, and a pull-down resistor connected between the second electrical terminal of the load and ground. ### Claim 7 (depends on 6) The apparatus of claim 6 wherein the resistance values of the pull-up resistor and the pull-down resistor are preselected such that when the high side driver and the low side driver are both controlled to their respective off states the voltage at the first electrical terminal of the load is between the high-side low voltage threshold and the high-side high voltage threshold and the voltage at the second electrical terminal of the load is between the low-side low voltage threshold and the low-side high voltage threshold when the short circuited load condition is not present. ### Claim 8 (depends on 7) The apparatus of claim 7 wherein the diagnostic circuit is configured to sense and identify the first fault condition, the second fault condition, the third fault condition, the fourth fault condition, the fifth fault condition, and the sixth fault condition based on the high-side overcurrent logic signal, the low-side overcurrent logic signal, a signal from the high-side voltage comparison means, and a signal from the low-side voltage comparison means. ### Claim 9 A method of diagnosing faults in an apparatus for controlling the application of electrical power to a load having a first electrical terminal and a second electrical terminal, the apparatus comprising: a controller; a high side driver electrically connected to a voltage supply and to the first electrical terminal of the load, the high side driver controllable to an on state wherein current flow from the voltage supply to the load is enabled and to an off state wherein current flow from the voltage supply to the load is disabled; a low side driver electrically connected to the second electrical terminal of the load and to a ground connection, the low side driver controllable to an on state wherein current flow from the load to the ground connection is enabled and to an off state wherein current flow from the load to the ground connection is disabled; and a diagnostic circuit configured to sense a fault condition and to generate a signal indicative of the fault condition; the method comprising the steps of: sensing and identifying an open load fault condition when the open load fault condition is present; sensing and identifying a high-side short circuit to battery fault condition when the high-side short circuit to battery fault condition is present; sensing and identifying a low-side short circuit to ground fault condition when the low-side short circuit to ground fault condition is present; sensing and identifying a high-side short circuit to ground fault condition when the high-side short circuit to ground fault condition is present; sensing and identifying a low-side short circuit to battery fault condition when is present; sensing and identifying a short circuited load fault condition when is present; and indicating a “no fault” condition when none of the open load fault condition, the high-side short circuit to battery fault condition, the low-side short circuit to ground fault condition, the high-side short circuit to ground fault condition, the low-side short circuit to battery fault condition, and the short circuited load fault condition are present. ### Claim 10 (depends on 9) The method of claim 9 further comprising the steps of: sensing if a fault condition results in current through the high side driver, the low side driver, and/or the load exceeding a predetermined current threshold, and sending a first control signal to control the high side driver to its off state and a second control signal to control the low side driver to its off state when a fault condition that results in current through the high side driver, the low side driver, and/or the load exceeding a predetermined current threshold is sensed. ### Claim 11 (depends on 10) The method of claim 10 wherein the fault condition that results in current through the high side driver, the low side driver, and/or the load exceeding the predetermined current threshold being sensed is the high-side short circuit to ground fault condition, the low-side short circuit to battery fault condition, or the short circuited load fault condition. ### Claim 12 (depends on 9) The method of claim 9, further comprising the steps of: monitoring a current through the high side driver from the voltage supply to the first electrical terminal of the load and generating a high-side overcurrent logic signal indicative of whether the current through the high side driver is above or below a predetermined high-side current threshold; monitoring a current through the low side driver from the second electrical terminal of the load to the ground connection and generating a low-side overcurrent logic signal indicative of whether the current through the low side driver is above or below a predetermined low-side current threshold; providing a first latch configured to capture the state of the high-side overcurrent logic signal; and providing a second latch configured to capture the state of the low-side overcurrent logic signal. ### Claim 13 (depends on 12) The method of claim 12, further comprising the steps of: providing at least one current source configured to be connectable to the first electrical terminal of the load so as to be able to charge and/or discharge a first capacitor connected from the first electrical terminal of the load to the ground connection, providing a high-side voltage comparison means configured to indicate whether the voltage at the first electrical terminal of the load is less than a high-side low voltage threshold, between the high-side low voltage threshold and a high-side high voltage threshold, or above the high-side high voltage threshold, wherein the high-side high voltage threshold is a higher voltage than the high-side low voltage threshold, providing at least one current source configured to be connectable to the second electrical terminal of the load so as to be able to charge and/or discharge a second capacitor connected from the second electrical terminal of the load to the ground connection, and providing a low-side voltage comparison means configured to indicate whether the voltage at the second electrical terminal of the load is less than a low-side low voltage threshold, between the low-side low voltage threshold and a low-side high voltage threshold, or above the low-side high voltage threshold, wherein the low-side high voltage threshold is a higher voltage than the low-side low voltage threshold. ### Claim 14 (depends on 13) The method of claim 13, further comprising the steps of: providing a pull-up resistor connected between a reference voltage source and the first electrical terminal of the load, and providing a pull-down resistor connected between the second electrical terminal of the load and ground. ### Claim 15 (depends on 14) The method of claim 14 further comprising the step of preselecting the resistance values of the pull-up resistor and the pull-down resistor such that when the high side driver and the low side driver are both controlled to their respective off states the voltage at the first electrical terminal of the load is between the high-side low voltage threshold and the high-side high voltage threshold and the voltage at the second electrical terminal of the load is between the low-side low voltage threshold and the low-side high voltage threshold when the short circuited load condition is not present. ### Claim 16 (depends on 15) The method of claim 15 wherein the steps of: sensing and identifying an open load fault condition when the open load fault condition is present, sensing and identifying a high-side short circuit to battery fault condition when the high-side short circuit to battery fault condition is present, sensing and identifying a low-side short circuit to ground fault condition when the low-side short circuit to ground fault condition is present, sensing and identifying a high-side short circuit to ground fault condition when the high-side short circuit to ground fault condition is present, sensing and identifying a low-side short circuit to battery fault condition when is present, sensing and identifying a short circuited load fault condition when is present, and indicating a “no fault” condition when none of the open load fault condition, the high-side short circuit to battery fault condition, the low-side short circuit to ground fault condition, the high-side short circuit to ground fault condition, the low-side short circuit to battery fault condition, and the short circuited load fault condition are present are based on the high-side overcurrent logic signal, the low-side overcurrent logic signal, a signal from the high-side voltage comparison means, and a signal from the low-side voltage comparison means.