WO2015200132A1 - Circuit and method for detecting short circuit failure of a switching transistor - Google Patents

Circuit and method for detecting short circuit failure of a switching transistor Download PDF

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Publication number
WO2015200132A1
WO2015200132A1 PCT/US2015/036701 US2015036701W WO2015200132A1 WO 2015200132 A1 WO2015200132 A1 WO 2015200132A1 US 2015036701 W US2015036701 W US 2015036701W WO 2015200132 A1 WO2015200132 A1 WO 2015200132A1
Authority
WO
WIPO (PCT)
Prior art keywords
output
circuit
gate
transistor
coupled
Prior art date
Application number
PCT/US2015/036701
Other languages
French (fr)
Inventor
Alexander Mednik
Rohit Tirumala
Mark Tan
Simon Krugly
Original Assignee
Microchip Technology Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Microchip Technology Inc. filed Critical Microchip Technology Inc.
Priority to JP2016574403A priority Critical patent/JP2017525243A/en
Priority to CN201580034099.XA priority patent/CN106797114A/en
Priority to EP15733977.1A priority patent/EP3158616A1/en
Priority to KR1020177001927A priority patent/KR20170024005A/en
Priority to TW104119975A priority patent/TWI580182B/en
Publication of WO2015200132A1 publication Critical patent/WO2015200132A1/en

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/04—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned
    • H02H3/044—Checking correct functioning of protective arrangements, e.g. by simulating a fault
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/26—Testing of individual semiconductor devices
    • G01R31/2607—Circuits therefor
    • G01R31/2621—Circuits therefor for testing field effect transistors, i.e. FET's
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/52—Testing for short-circuits, leakage current or ground faults
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/04—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
    • H02H3/093—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current with timing means

Definitions

  • a circuit and method are provided detecting a persistent short circuit in a power MOSFET for the purpose of protecting a load from over-current.
  • Figure 1 depicts a prior art protection circuit 100 for protecting a load 110 from over- current stress due to a short-circuit failure 199 of a transistor 102, the protection circuit 100 comprising a current sense resistor 103 and a circuit breaker 106.
  • the load 110 receives power from an input source of voltage 101 through the transistor 102 biased into conduction by a driver 105.
  • the circuit breaker 106 disconnects the load 110 from the input voltage source 103.
  • the prior art protection circuit 100 suffers high cost of components and is not well suited for integration in a monolithic die with the driver 105.
  • circuit breaker 106 does not provide adequate protection in a system with low headroom voltage.
  • the present invention proposes a method and circuit for detecting a short circuit failure of a switching transistor adapted for connecting a load to an input source of voltage, the method comprising: a step of detecting an over-current condition at the load; a step of biasing the switching transistor non-conductive when the over-current condition is detected; a step of a blanking delay to allow the over-current condition to clear; a step of reporting a fault status in the case of the over-current condition persisting past the blanking delay.
  • Figure 1 depicts a prior art protection circuit.
  • Figure 2 depicts one embodiment of a protection circuit according to the present invention.
  • Figure 3 depicts another embodiment of a protection circuit according to the present invention.
  • FIG. 2 depicts a detection circuit 200 of the present invention for detecting the short- circuit failure 199 of the transistor 102, the circuit 200 comprising: a current sense input CS; a driver output GT; a flag output FAULT; a comparator 201 for comparing voltage at CS to a reference REF and reporting a comparison result at an output; a driver 202 for biasing the transistor 102 non-conductive when voltage at CS exceeds REF; a circuit 203 for generating a blanking delay at the output of the comparator 201 for allowing the over-current condition to clear; a gate 204 reporting the short-circuit failure 199 at the flag output FAULT when the condition of the CS voltage exceeding REF persists past the blanking delay generated by circuit 203.
  • a short-circuit failure 199 has occurred.
  • the system can take appropriate steps in response to short-circuit failure 199. For example, the system can disable input source of voltage 101 or can disconnect load 110 from input source of voltage 101.
  • Figure 3 depicts the detection circuit 200 of Figure 2, wherein a circuit 203 generates a blanking delay at the current sense input CS allowing the over-current condition to clear before the voltage at CS propagates to the comparator 201.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Protection Of Static Devices (AREA)
  • Emergency Protection Circuit Devices (AREA)
  • Electronic Switches (AREA)
  • Power Conversion In General (AREA)

Abstract

A circuit and method are provided detecting a persistent short circuit in a power MOSFET for the purpose of protecting a load from over-current. The method determining a fault condition in a circuit comprising a switch provided with a gate, a first terminal and a second terminal, the first terminal being coupled to a load and the second terminal being coupled to a current sense element, and after a blanking delay, comparing a voltage at the current sense element with a reference voltage and asserting a signal indicating a fault condition if the voltage at the current sense element exceeds the reference voltage.

Description

CIRCUIT AND METHOD FOR DETECTING SHORT CHICOT FAILURE OF A
SWITCHING TRANSISTOR
CROSS REFERENCE TO RELATED APPLICATION
[0001] This patent application claims priority to U.S. Application No. 14/743,945, filed on June 18, 2015, and titled "Circuit and Method for Detecting Short Circuit Failure of a Switching Transistor," which claims priority to U.S. Provisional Application No. 62/016,090, filed on June 23, 2014, and titled "Circuit and Method for Detecting Short Circuit Failure of a Switching Transistor, ," which are incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] A circuit and method are provided detecting a persistent short circuit in a power MOSFET for the purpose of protecting a load from over-current.
BACKGROUND OF THE INVENTION
[0003] Figure 1 depicts a prior art protection circuit 100 for protecting a load 110 from over- current stress due to a short-circuit failure 199 of a transistor 102, the protection circuit 100 comprising a current sense resistor 103 and a circuit breaker 106. The load 110 receives power from an input source of voltage 101 through the transistor 102 biased into conduction by a driver 105. In operation, when a voltage threshold is exceeded across the sense resistor 103, the circuit breaker 106 disconnects the load 110 from the input voltage source 103.
[0004] The prior art protection circuit 100 suffers high cost of components and is not well suited for integration in a monolithic die with the driver 105. In addition, circuit breaker 106 does not provide adequate protection in a system with low headroom voltage.
[0005] What is needed is an improved circuit and method for performing direct detection of the transistor failure.
SUMMARY OF THE INVENTION
[0006] The present invention proposes a method and circuit for detecting a short circuit failure of a switching transistor adapted for connecting a load to an input source of voltage, the method comprising: a step of detecting an over-current condition at the load; a step of biasing the switching transistor non-conductive when the over-current condition is detected; a step of a blanking delay to allow the over-current condition to clear; a step of reporting a fault status in the case of the over-current condition persisting past the blanking delay.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 depicts a prior art protection circuit.
[0008] Figure 2 depicts one embodiment of a protection circuit according to the present invention.
[0009] Figure 3 depicts another embodiment of a protection circuit according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0010] Figure 2 depicts a detection circuit 200 of the present invention for detecting the short- circuit failure 199 of the transistor 102, the circuit 200 comprising: a current sense input CS; a driver output GT; a flag output FAULT; a comparator 201 for comparing voltage at CS to a reference REF and reporting a comparison result at an output; a driver 202 for biasing the transistor 102 non-conductive when voltage at CS exceeds REF; a circuit 203 for generating a blanking delay at the output of the comparator 201 for allowing the over-current condition to clear; a gate 204 reporting the short-circuit failure 199 at the flag output FAULT when the condition of the CS voltage exceeding REF persists past the blanking delay generated by circuit 203. Thus, when the flag output FAULT is asserted, a short-circuit failure 199 has occurred. The system can take appropriate steps in response to short-circuit failure 199. For example, the system can disable input source of voltage 101 or can disconnect load 110 from input source of voltage 101.
[0011] Figure 3 depicts the detection circuit 200 of Figure 2, wherein a circuit 203 generates a blanking delay at the current sense input CS allowing the over-current condition to clear before the voltage at CS propagates to the comparator 201.

Claims

What is claimed is:
1. A method of determining a fault condition in a circuit, comprising:
turning off a switch comprising a gate and a first terminal and a second terminal, the first terminal coupled to a load and the second terminal coupled to a current sense element; and
after a blanking delay, comparing a voltage at the current sense element with a reference voltage and asserting a signal indicating a fault condition if the voltage at the current sense element exceeds the reference voltage.
2. The method of claim 1, wherein the fault condition is a short circuit failure of the switch.
3. A protection circuit, comprising :
a switching transistor having a first terminal, a second terminal, and a gate;
a current sense element coupled to the switching transistor;
a comparator with a first input terminal, a second input terminal, and an output, the first input terminal coupled the current sense element and the second input terminal coupled to a reference voltage;
a gate driver with an input coupled to the output of the comparator and with an output coupled to a gate of the transistor, wherein the output of the gate driver is high during normal operation to turn on the transistor and low during a mode to determine whether a fault exists in the transistor;
a blanking circuit for generating a blanking delay, the blanking circuit having an input coupled to the output of the comparator and an output; and
a logic gate for receiving the output of the blanking circuit and the output of the gate driver, wherein the logic gate outputs a signal indicating a fault condition in the transistor.
4. The circuit of claim 3, wherein the fault condition is a short circuit failure of the transistor.
5. The protection circuit of claim 3 , wherein the logic gate is an AND gate comprising: an inverting input for receiving the output of the gate driver; and a non-inverting input for receiving the output of the blanking circuit.
6. The protection circuit of claim 4, wherein the logic gate is an AND gate comprising:
an inverting input for receiving the output of the gate driver; and a non-inverting input for receiving the output of the blanking circuit.
7. A protection circuit, comprising:
a switching transistor having a first terminal, a second terminal, and a gate;
a current sense element coupled to the switching transistor;
a blanking circuit for generating a blanking delay, the blanking circuit having an input coupled to the current sense element and an output;
a comparator with a first input terminal, a second input terminal, and an output, the first input terminal coupled to the output of the blanking circuit and the second input terminal coupled to a reference voltage;
a gate driver with an input coupled to the output of the comparator and with an output coupled to a gate of the transistor, wherein the output of the gate driver is high during normal operation to turn on the transistor and low during a mode to determine whether a fault exists in the transistor; and
a logic gate for receiving the output of the comparator and the output of the gate driver, wherein the logic gate outputs a signal indicating a fault condition in the transistor.
8. The circuit of claim 7, wherein the fault condition is a short circuit failure of the transistor.
9. The protection circuit of claim 7, wherein the logic gate is an AND gate comprising:
an inverting input for receiving the output of the gate driver; and
a non-inverting input for receiving the output of the comparator.
10. The protection circuit of claim 8, wherein the logic gate is an AND gate comprising:
an inverting input for receiving the output of the gate driver; and
a non- inverting input for receiving the output of the comparator.
PCT/US2015/036701 2014-06-23 2015-06-19 Circuit and method for detecting short circuit failure of a switching transistor WO2015200132A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
JP2016574403A JP2017525243A (en) 2014-06-23 2015-06-19 Circuit and method for detecting short circuit failure of switching transistor
CN201580034099.XA CN106797114A (en) 2014-06-23 2015-06-19 For the circuit and method of detection switch transistor short trouble
EP15733977.1A EP3158616A1 (en) 2014-06-23 2015-06-19 Circuit and method for detecting short circuit failure of a switching transistor
KR1020177001927A KR20170024005A (en) 2014-06-23 2015-06-19 Circuit and method for detecting short circuit failure of a switching transistor
TW104119975A TWI580182B (en) 2014-06-23 2015-06-22 Circuit and method for detecting short circuit failure of a switching transistor

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US201462016090P 2014-06-23 2014-06-23
US62/016,090 2014-06-23
US14/743,945 US9658276B2 (en) 2014-06-23 2015-06-18 Circuit and method for detecting short circuit failure of a switching transistor
US14/743,945 2015-06-18

Publications (1)

Publication Number Publication Date
WO2015200132A1 true WO2015200132A1 (en) 2015-12-30

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2015/036701 WO2015200132A1 (en) 2014-06-23 2015-06-19 Circuit and method for detecting short circuit failure of a switching transistor

Country Status (7)

Country Link
US (1) US9658276B2 (en)
EP (1) EP3158616A1 (en)
JP (1) JP2017525243A (en)
KR (1) KR20170024005A (en)
CN (1) CN106797114A (en)
TW (1) TWI580182B (en)
WO (1) WO2015200132A1 (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9392460B1 (en) 2016-01-02 2016-07-12 International Business Machines Corporation Continuous user authentication tool for mobile device communications
CN108616108A (en) * 2016-12-12 2018-10-02 中国航空工业集团公司西安航空计算技术研究所 A kind of current foldback circuit of tracking failure severity
CN107370117B (en) * 2017-07-11 2019-04-30 深圳金三立视频科技股份有限公司 A kind of output overcurrent and short-circuit protection circuit and a kind of electronic equipment
US10782347B2 (en) * 2017-10-23 2020-09-22 Nxp B.V. Method for identifying a fault at a device output and system therefor
CN110446285B (en) * 2018-05-02 2022-02-25 佛山市顺德区美的电热电器制造有限公司 Electric cooking device and electromagnetic heating system for electric cooking device
US10965215B2 (en) * 2019-08-15 2021-03-30 Microchip Technology Incorporated Constant on-time buck converter with calibrated ripple injection having improved light load transient response and reduced output capacitor size
KR102456560B1 (en) 2020-08-25 2022-10-19 (주) 트리노테크놀로지 Power semiconductor device with improved short-circuit property
CN112968429B (en) * 2021-02-04 2023-02-28 高新兴物联科技股份有限公司 Switch short-circuit protection circuit based on P-channel MOS tube
US11929698B2 (en) 2021-03-23 2024-03-12 Snap-On Incorporated Short circuit protection for a BLDC motor
CN116990655B (en) * 2023-09-26 2023-12-19 安徽大学 Transistor short circuit detection circuit and method based on drain-source voltage change rate

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1693942A1 (en) * 2005-02-21 2006-08-23 Yazaki Corporation Overcurrent detecting device
US20070247774A1 (en) * 2006-04-21 2007-10-25 Cheng Xiao-Chang Noise immune over current protection with inherent current limiting for switching power converter
EP2146430A1 (en) * 2007-05-14 2010-01-20 Yasaki Corporation Overcurrent protection device
US20130214806A1 (en) * 2012-02-21 2013-08-22 Hamilton Sundstrand Corporation Self-test of over-current fault detection
US20130342938A1 (en) * 2012-06-20 2013-12-26 Fairchild Korea Semiconductor Ltd. Short sensing circuit, short sensing method and power supply device comprising the short sensing circuit

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2734974B1 (en) * 1995-05-31 1997-07-18 Sgs Thomson Microelectronics MICROCONTROLLER FOR IMAGE DISPLAY APPLICATIONS ON TUBE WITH CATHODE DISPLAY.
US6185082B1 (en) * 1999-06-01 2001-02-06 System General Corporation Protection circuit for a boost power converter
US7593245B2 (en) * 2005-07-08 2009-09-22 Power Integrations, Inc. Method and apparatus to limit maximum switch current in a switching power supply
US8018694B1 (en) * 2007-02-16 2011-09-13 Fairchild Semiconductor Corporation Over-current protection for a power converter
JP5110700B2 (en) * 2008-03-27 2012-12-26 太平洋セメント株式会社 Combustion waste fuel conversion system and fuel conversion method
US7986149B2 (en) * 2008-08-19 2011-07-26 Infineon Technologies Austria Ag System and method for adaptive load fault detection
JP5315155B2 (en) * 2009-07-23 2013-10-16 日立オートモティブシステムズ株式会社 Semiconductor element control device, automotive electrical system
JP5307660B2 (en) * 2009-07-30 2013-10-02 新日本無線株式会社 Short circuit protection circuit for switching drive circuit
JP2012010577A (en) * 2010-05-28 2012-01-12 Panasonic Corp Overcurrent protection circuit and overcurrent protection method
US8331072B1 (en) * 2010-08-25 2012-12-11 Maxim Integrated Products, Inc. Timer controlled, short and open circuit fault detection with slew-rate boosted output driver
JP5724913B2 (en) * 2012-03-15 2015-05-27 トヨタ自動車株式会社 Power converter
EP2712084B1 (en) * 2012-09-20 2019-11-06 Infineon Technologies AG Semiconductor device including short-circuit protection with a variable threshold
US9520879B2 (en) * 2014-06-18 2016-12-13 Texas Instruments Incorporated Adaptive blanking timer for short circuit detection

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1693942A1 (en) * 2005-02-21 2006-08-23 Yazaki Corporation Overcurrent detecting device
US20070247774A1 (en) * 2006-04-21 2007-10-25 Cheng Xiao-Chang Noise immune over current protection with inherent current limiting for switching power converter
EP2146430A1 (en) * 2007-05-14 2010-01-20 Yasaki Corporation Overcurrent protection device
US20130214806A1 (en) * 2012-02-21 2013-08-22 Hamilton Sundstrand Corporation Self-test of over-current fault detection
US20130342938A1 (en) * 2012-06-20 2013-12-26 Fairchild Korea Semiconductor Ltd. Short sensing circuit, short sensing method and power supply device comprising the short sensing circuit

Also Published As

Publication number Publication date
US20150369854A1 (en) 2015-12-24
CN106797114A (en) 2017-05-31
EP3158616A1 (en) 2017-04-26
JP2017525243A (en) 2017-08-31
KR20170024005A (en) 2017-03-06
US9658276B2 (en) 2017-05-23
TWI580182B (en) 2017-04-21
TW201613269A (en) 2016-04-01

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