JP2009264959A - Connection abnormality detection device and onboard electronic apparatus using this device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a connection abnormality detection device that precisely measures minute changes in resistance in a solder joint regardless of variations or changes over time in electronic components and early detects a connection abnormality in the solder joint; and an onboard electronic apparatus using the device. <P>SOLUTION: Voltage measuring means 108 measures the voltage of a connection point V1 between a resistivity measuring solder joint 102b and a constant-voltage supply 105 and the voltages of points V2 and V3 at both ends of a reference resistor 106. Resistance calculating means 109 calculates the resistance Rr of the resistivity measuring solder joint 102b with use of the measured voltages Vout1, Vout2 and Vout3 of the three points V1, V2 and V3. Abnormality determination means 110 determines a connection abnormality in accordance with a change in resistance ΔRr of the resistivity measuring solder joint 102b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a connection abnormality detection device for detecting a connection abnormality in a solder connection portion of a semiconductor package mounted on a circuit board used in a vehicle-mounted electronic device or the like, and a vehicle-mounted electronic device using the device.

  In recent years, package substrates have been widely used as main components of electronic devices. The package substrate is, for example, a printed circuit board on which a semiconductor package represented by a small electronic component such as a BGA (Ball Grid Array) package or a CSP (Chip Size Package) is mounted. It is. The BGA package has input / output pads arranged on the back side of the package and is widely used for surface mounting of multi-pin ICs. The CSP has the same basic structure as the BGA package and is almost the same as an IC chip. It is an ultra-small semiconductor package that realizes its size.

  A semiconductor package is generally formed using a plastic resin or a ceramic such as alumina as a main material, and is used by being mounted on a circuit board formed of an epoxy resin material or the like. At that time, temperature fluctuations repeatedly occur due to fluctuations in heat and environmental temperature generated in the IC itself constituting the semiconductor package, and mechanical stress due to the difference in linear expansion coefficient is generated between the semiconductor package and the circuit board. In addition, a connection abnormality occurs in the solder connecting the semiconductor package and the circuit board on which the semiconductor package is mounted. In order to detect this solder connection abnormality, a technology for providing a solder connection portion for confirming electrical connection near the corner of a BGA package, which has the largest mechanical stress and theoretically has a short solder connection life Is disclosed (for example, see Patent Document 1).

  Also disclosed is a technique for detecting a crack in a solder connection portion. That is, the LSI side of the solder connection portion for electrical connection confirmation is electrically connected to GND. The substrate side is pulled up with a resistor and connected to the plus side of the comparator, and the reference power supply is connected to the minus side of the comparator. When the impedance generated when the crack is generated in the solder connection portion for confirming electrical connection and the divided value of the pull-up resistor reach the reference power supply voltage, the output value of the comparator changes. This is a technique for detecting a change in the output value of the comparator and detecting a connection abnormality in the solder connection portion (see, for example, Patent Document 2).

  Furthermore, there is also a disclosure of a technique that realizes connection abnormality of a solder connection part for electrical connection confirmation by a latch circuit, an OR circuit, and a selector circuit. That is, in the BGA package, there are a plurality of solder connection portions for electrical connection confirmation, and the substrate has a wiring pattern derived from the solder connection portion of the BGA package. Then, it is a technology that takes in a potential change due to an abnormal connection of solder by a latch circuit, detects an abnormal state with an OR circuit, and identifies a solder connection portion where an abnormality has occurred from a plurality of solder connection portions with a selector circuit. (For example, refer to Patent Document 3).

Japanese Patent Laid-Open No. 10-93297 (paragraph 0020-paragraph 0029, FIG. 1) JP 2001-228191 A (paragraph 0012-paragraph 0014, FIG. 1) JP 2007-35889 A (summary column, FIG. 3)

  According to the technique disclosed in Patent Document 1 or Patent Document 2, a critical connection is made to a signal solder connection portion by providing a solder connection portion for confirming electrical connection in the vicinity of a corner of a semiconductor package and checking a crack. Abnormalities can be detected before defects occur. Further, according to the technique disclosed in Patent Document 3, it is effective at the time of failure diagnosis by recording which solder connection portion has an abnormality.

  By the way, due to the recent miniaturization of semiconductor packages and the increase in signal terminals, the solder connection part for electrical connection confirmation has to be placed close to the signal solder connection part. The closer the solder connection part for electrical connection confirmation is, the more likely an abnormality such as a crack has occurred in the signal solder connection part when an abnormality is detected in the solder connection part for electrical connection confirmation Becomes higher. In particular, when high reliability such as in-vehicle parts is required, it is necessary to detect the connection abnormality of the solder connection part for signals early and accurately. It is necessary to measure the resistance change with high accuracy.

  However, Patent Document 1 does not disclose a specific method for detecting a change in resistance value. In the disclosed technique of Patent Document 2, the threshold value can be adjusted with the reference power supply voltage, but a minute resistance change cannot be measured due to variations in pull-up resistance, temperature changes, and comparator offsets. Therefore, there is a problem that a minute resistance change at the beginning of connection abnormality cannot be detected, and early detection of abnormality is difficult. Furthermore, in the disclosed technique of Patent Document 3, a digital circuit called a latch circuit is used, and the threshold value is near the center of the power supply voltage and GND of the latch circuit. There is a problem that cannot be detected except in the case of.

  Further, as disclosed in Patent Document 1 or Patent Document 2, if an abnormality is detected only near the corner of the semiconductor package, the life is obviously wasted if the locations where the abnormality should be detected are concentrated in the center. In such a configuration, there is a problem that excessive reliability must be ensured in order to ensure a necessary life.

  The present invention has been made to solve the above-mentioned problems. A small change in resistance value of a solder connection portion is accurately measured regardless of variations in electronic components, aging, and temperature fluctuations. An object of the present invention is to obtain a connection abnormality detection device that detects an abnormality at an early stage, and an in-vehicle electronic device using the device.

  The connection abnormality detection device according to the present invention is a connection abnormality detection device that detects a connection abnormality of a solder connection portion between a semiconductor package mounted on a circuit board and the circuit board, and the solder connection portion includes a constant voltage source. Including a resistance measurement solder connection portion connected to the resistance measurement solder connection portion connected to the resistance measurement solder connection portion by an internal wiring of the semiconductor package, and connected to the wiring extraction solder connection portion. When a reference resistance having a known resistance value, a connection point between the resistance measurement solder connection portion and the constant voltage source is V1, one end of the reference resistance is V2, and the other end of the reference resistance is V3, A voltage measuring means for measuring the voltage of V1, the voltage of V2, and the voltage of V3; the voltage of V1, the voltage of V2, and the voltage of V3 measured by the voltage measuring means; A resistance value calculating means for calculating a resistance value of the resistance measuring solder connecting portion using a resistance, and a connection abnormality based on a change in the resistance value of the resistance measuring solder connecting portion calculated by the resistance value calculating means. Abnormality determining means for determining.

  According to the connection abnormality detecting device according to the present invention, a minute change in resistance value of the solder connection portion is accurately measured regardless of variations in electronic components, aging, and temperature fluctuations, and the connection abnormality of the solder connection portion is detected at an early stage. Can be detected.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of a connection abnormality detection device according to the invention and an in-vehicle electronic device using the device will be described with reference to the accompanying drawings. Note that the present invention is not limited to these embodiments.

Embodiment 1 FIG.
First, the principle configuration of the connection abnormality detection device according to the present invention will be described. FIG. 1 is a block diagram showing the principle of the present invention. In FIG. 1, a semiconductor package 101 is mounted on a circuit board 103 via solder connection portions 102a, 102b, and 102c. The solder connection part 102a is a signal solder connection part, and the solder connection part 102b is a resistance measurement solder connection part to be subjected to resistance measurement for detecting a connection abnormality. The solder connection portion 102 c is a wiring connection solder connection portion, and is connected to the resistance measurement solder connection portion 102 b by the IC internal wiring 104 of the semiconductor package 101.

  The side in contact with the circuit board 103 of the resistance measurement solder connection portion 102 b is connected to the constant voltage source 105. Further, the side of the wiring connection solder connection portion 102c that is in contact with the circuit board 103 is connected to a common potential 107 common to a connection abnormality detection device such as a ground potential via a high-precision reference resistor 106.

  The voltage measuring means 108 includes a point V1 where the resistance measurement solder connection portion 102b and the constant voltage source 105 are connected, a point V2 where the wiring connection solder connection portion 102c and the reference resistor 106 are connected, and the reference resistor 106 and the common potential. The voltage at point V3 to which 107 is connected is measured. Then, the resistance calculating means 109 uses the measured voltage values Vout1, Vout2, and Vout3 of the voltage measuring points V1, V2, and V3 measured by the voltage measuring means 108, so that the resistance measurement solder connection portion 102b is used in a method described later. The resistance value Rr is calculated. Then, a connection abnormality is determined by the abnormality determination means 110 based on the resistance value Rr of the resistance measurement solder connection portion 102b. In addition, the code | symbol 111 in FIG. 1 has shown the resistance of the to-be-resisted measurement solder connection part 102b.

  The principle configuration of the connection abnormality detection device according to the present invention has been described above. Next, specific embodiments will be described. FIG. 2 is a block diagram for explaining a connection abnormality detection device according to Embodiment 1 of the present invention, and parts common to FIG. In the following embodiments, a case where a solder ball is used as the solder connection portion will be described as an example.

  Since the resistance-measured solder ball 102b is a resistance value measurement target, the mechanical stress due to the thermal expansion difference between the semiconductor package 101 and the circuit board 103 is the largest, and theoretically the solder connection life is as shown in FIG. It is located at the outermost periphery, which is supposed to be short. The resistance measuring solder ball 102b is not necessarily located at the outermost peripheral portion of the semiconductor package 101, but may be located farther from the center of the semiconductor package 101 than the signal solder ball 102a. By making the resistance measurement solder ball 102b and the signal solder ball 102a close to each other, it is possible to accurately detect the connection abnormality of the signal solder ball 102a, and it is not necessary to ensure excessive reliability and is relatively inexpensive. Long service life can be ensured by simple life design.

  The solder ball 102c for wiring extraction is located at the center of the semiconductor package 101 with relatively high connection reliability. This is because the closer to the center, the smaller the displacement due to the difference in thermal expansion between the semiconductor package 101 and the circuit board 103 and the smaller the mechanical stress applied to the solder ball 102. Note that the solder ball for wiring extraction 102c is not necessarily located at the center of the semiconductor package 101, but may be located closer to the center of the semiconductor package 101 than the resistance measurement solder ball 102b. In this case, the solder balls at the center of the semiconductor package 101 are assigned for signals. Further, by connecting a plurality of wiring take-out solder balls 102c and connecting them by the IC internal wiring 104 and the circuit board 103, the connection reliability of the wiring take-out solder balls 102c is increased, and the resistance value of the resistance-measurement solder balls 102b is increased. It is possible to accurately detect the connection error.

  The output of the switch 201 serving as a voltage selection unit is controlled by a control signal such as an analog switch or a relay. The switch 201 includes a voltage Vout1 at a point V1 where the resistance 111 of the resistance-measured solder ball 102b and the constant voltage source 105 are connected, a voltage Vout2 at a point V2 where the wiring connection solder connection portion 102c and the reference resistor 106 are connected, It is possible to select and input three voltages Vout3 at the point V3 where the reference resistor 106 and the common potential 107 are connected, and the output is input as an analog signal to the amplifier 202 which is an amplifying means and amplified. The The analog signal amplified by the amplifier 202 is converted into a digital signal by the AD converter 203 which is AD conversion means.

  The signal converted into a digital signal by the AD converter 203 is processed by the microcontroller 204. The microcontroller 204 includes a control unit 205 that controls the switch 201, a memory 206 that records the voltage Vout1, the voltage Vout2, the voltage Vout3, and the resistance value Rr of the resistance measurement solder ball 102b, and data recorded in the memory 206. The resistance change Rr is calculated using the resistance value calculation unit 207 that calculates the resistance value Rr based on the resistance value, the resistance value Rr calculated by the resistance value calculation unit 207, and the initial resistance value Rr0 stored in the memory 206 in advance. A resistance change calculation unit 208 and an abnormality determination unit 209 that outputs a connection abnormality determination signal based on the resistance change ΔRr calculated by the resistance change calculation unit 208 are configured.

  FIG. 3 shows the equivalent circuit of FIG. In FIG. 3, the semiconductor package 101, the solder ball 102, the circuit board 103, and the IC internal wiring 104 are omitted, and only the resistance 111 of the resistance measurement solder ball 102b is displayed.

  The connection abnormality detection device according to the first embodiment is configured as described above. Next, a method for measuring the resistance value Rr of the resistance-measured solder ball 102b, which is a resistance value measurement target, will be described using mathematical expressions. .

  First, the amplifier 202 will be described supplementarily with reference to FIG. FIG. 4 shows a general configuration example of the amplifier 202. In general, the amplifier 202 is often configured by an operational amplifier 401 and resistors 402 and 403. In this case, the amplification factor is determined by a resistance value ratio of the resistor 402 and the resistor 403.

  Next, the voltage measurement points V1, V2, and V3 and the output of the AD converter 203, that is, the voltages Vout1, Vout2, and Vout3 stored in the memory 206 of the microcontroller 204 will be described with reference to FIGS. Assuming that the resistance value between the voltage measurement points V1, V2, and V3 and the common potential 107 is a variable r, the voltage Vout is expressed by the following equation (1).

Here, each symbol in Formula 1 represents the following.
E: voltage of the constant voltage source 105,
ΔE: voltage error of the constant voltage source 105,
Rr: resistance value of the resistance 111 of the resistance measurement solder ball 102b,
Rref: resistance value of the reference resistor 106,
Voff_amp: the offset voltage of the operational amplifier 401,
A: amplification factor of the amplifier 202,
ΔA: gain error of amplifier 202,
Voff_adc: offset voltage of the AD converter 203

  Among the symbols constituting Equation 1, the voltage E of the constant voltage source 105, the resistance value Rref of the reference resistor 106, and the amplification factor A of the amplifier 202 are known by design values, whereas the constant voltage source A voltage error ΔE 105, an offset voltage Voff_amp of the operational amplifier 401, an amplification factor error ΔA of the amplifier 202, and an offset voltage Voff_adc of the AD converter 203 are unknown numbers that fluctuate due to manufacturing variations, ambient temperature changes, or secular changes. The amplification factor error ΔA of the amplifier 202 is also affected by the resistance error of the resistors 402 and 403 constituting the amplifier 202.

  When formula 1 is developed and arranged into terms that include variable r, which is a measured resistance, and terms that do not include it, the following formula 2 is obtained.

When the coefficient of the variable r, which is the measurement resistance of the first term in the equation 2, is a, and the second term is b, the following equation 3 is obtained.
Vout = a · r + b (Formula 3)

  It can be seen from Equation 3 that the voltage Vout recorded in the memory 206 of the microcontroller 204 is expressed by a linear equation of the measuring resistance r. By obtaining the constant terms a and b of Equation 3, the resistance value Rr of the resistance-measured solder ball 102b can be obtained with high accuracy.

Next, a method of calculating the resistance value Rr of the resistance measurement solder ball 102b will be described. Output values Vout1, Vout2, and Vout3 of the voltage observed at the voltage measurement points V1, V2, and V3 from the AD converter 203 are expressed as the following Expression 4, Expression 5, and Expression 6.
Vout1 = a · (Rr + Rref) + b (Formula 4)
Vout2 = a · Rref + b (Formula 5)
Vout3 = a · 0 + b = b (Formula 6)
From Equations 5 and 6, the values of a and b are expressed by the following Equation 7.
b = Vout3
a = (Vout2-Vout3) / Rref (Formula 7)
The resistance value Rr of the resistance-measurement solder ball 102b is expressed by the following expression 8 according to the expressions 4, 5 and 7.

  As described above, the resistance value Rr of the resistance-measured solder ball 102b can be measured with high accuracy within the error range of the resistance value Rref of the reference resistor 106 from the equation (8).

  Next, the operation of the connection abnormality detection device according to the first embodiment will be described with reference to the flowchart of FIG. 5 with reference to the equivalent circuit of FIG.

  First, in order to measure the voltage value of the point V1 in step S501, the switch 201 is set to A by the control signal of the control unit 205 of the microcontroller 204. In step S502, the output Vout1 of the AD converter 203 at this time is stored in the memory 206.

  Next, in order to measure the voltage value of the point V <b> 2 in step S <b> 503, the switch 201 is set to B by the control signal of the control unit 205 of the microcontroller 204. In step S504, the output Vout2 of the AD converter 203 at this time is stored in the memory 206.

  In step S505, the switch 201 is set to C by the control signal of the control unit 205 of the microcontroller 204 in order to measure the voltage value at the point V3. In step S506, the output Vout3 of the AD converter 203 at this time is stored in the memory 206.

  In this embodiment, the switch 201 is set in the order of A, B, and C, and the output of the AD converter 203 is stored in the memory 206 in the order of Vout1, Vout2, and Vout3. However, it is necessary to switch the switch 201 in this order. The switch 201 may be switched in any order.

  In step S507, the resistance value calculation unit 207 of the microcontroller 204 determines the resistance value of the resistance-measured solder ball 102b from the Vout1, Vout2, and Vout3 stored in the memory 206 and the known resistance value Rref of the reference resistor 106 in the above process. Rr is calculated according to Equation 8 above.

  In step S508, the resistance change calculation unit 208 of the microcontroller 204 calculates the difference between the resistance value Rr of the resistance-measured solder ball 102b calculated by the resistance value calculation unit 207 and the initial resistance value Rr0 as the resistance change ΔRr. The initial resistance value Rr0 and the processing in step S511 will be described later.

  In step S509, the abnormality determination unit 209 of the microcontroller 204 compares the resistance change ΔRr with a preset resistance change allowable value stored in the memory 206, and if the resistance change ΔRr is equal to or smaller than the resistance change allowable value. There is no connection abnormality, and the process returns to step S501. If the resistance change ΔRr is equal to or greater than the resistance change allowable value, it is determined that there is a connection abnormality, and a connection abnormality detection signal is output in step S510.

  In step S511, it is selected whether the resistance value Rr of the resistance measurement solder ball 102b calculated by the resistance value calculation unit 207 of the microcontroller 204 is stored in the memory 206 as the initial resistance value Rr0. In step S508, by calculating the difference between the resistance value Rr at the time of measurement and the initial resistance value Rr0 measured before and stored in the memory 206, the wiring connected to the resistance-measured solder ball 102b and the reference resistor 106 It is possible to cancel the resistance, and only the change in resistance value of the resistance-measured solder ball 102b is recorded, and based on this, the connection abnormality can be determined in step S509.

  The storage of the initial resistance value Rr0 in the memory 206 in step S512 is performed, for example, before the semiconductor package 101 and the circuit board 103 are repeatedly subjected to thermal cycle stress, that is, at the initial startup of the electronic device on which the semiconductor package 101 is mounted.

  In step S513, after the initial resistance value Rr0 is stored, the initial resistance value Rr0 is compared with the preset initial resistance allowable value stored in the memory 206, and the initial resistance value Rr0 is equal to or greater than the initial resistance allowable value. If so, a connection abnormality detection signal is output (step S510). Thereby, an initial failure can be found.

  As described above, according to the connection abnormality detection device according to the first embodiment, a minute resistance value change in the solder connection portion is accurately measured regardless of variations in electronic components, aging, and temperature fluctuations. Can be detected early.

Embodiment 2. FIG.
Next, a connection abnormality detection apparatus according to Embodiment 2 of the present invention will be described. FIG. 6 is a configuration diagram for explaining the connection abnormality detection device according to the second embodiment, and is an expanded embodiment that can measure the resistance values of a plurality of resistance measurement solder balls 102b provided at the corners of the semiconductor package. FIG.

  6, parts common to FIG. 1 are denoted by the same reference numerals, and description thereof is omitted. Further, for the sake of simplification, the display of the signal solder balls is omitted. In FIG. 6, resistance-measurement solder balls 102 b 1, 102 b 2, 102 b 3, and 102 b 4 to be measured for resistance values are provided at the corners of the semiconductor package 101. The resistance measurement solder balls 102b1, 102b2, 102b3, 102b4 are connected to one wiring extraction solder ball 102c near the center of the semiconductor package 101 by the IC internal wiring 104. The wiring extraction solder ball 102c is connected to the circuit board wiring. It is connected to the reference resistor 106 via 601. By using a common solder ball 102c for wiring extraction, it is possible to save a solder ball near the center of the semiconductor package 101 that is generally used for a signal line, and one high-precision reference resistor 106 that is usually expensive. There are advantages that can be realized.

  The resistance measurement solder balls 102b1, 102b2, 102b3, and 102b4 are connected to a wiring selection switch 603b, which is a wiring selection unit, via a circuit board wiring 602. The wiring selection switch 603b is for selecting which resistance measurement solder ball of the resistance measurement solder balls 102b1, 102b2, 102b3, 102b4 is to be measured.

  The circuit board wiring 602 is also connected to a potential selection switch 603a which is a wiring selection means. The potential selection switch 603a switches the voltage V11, V12, V13, V14 of the resistance measuring solder balls 102b1, 102b2, 102b3, 102b4 and the voltage V2, V3 across the reference resistor 106 to be measured. . Both the potential selection switch 603a and the wiring selection switch 603b are controlled by a control signal from the control unit 205 of the microcontroller 204. In this embodiment, since the internal resistance of the wiring selection switch 603b can be included as a voltage error of the constant voltage source 105 that does not require accuracy, there is no need to consider the internal resistance of the wiring selection switch 603b.

  Next, the operation of the connection abnormality detection device according to Embodiment 2 will be described with reference to FIG.

  First, in step S701, an initial value 1 is substituted into a counter variable i indicating which resistance measurement solder ball 102b is observed.

  In step S702, the wiring selection switch 603b is set to A1 and the potential selection switch 603a is set to A1 according to the control signal of the control unit 205 of the microcontroller 204. In step S703, the output value Vout1 of the AD converter 203 at that time is stored in the memory 206.

  In step S704, the wiring selection switch 603b is set to B and the potential selection switch 603a is set to B according to the control signal of the control unit 205 of the microcontroller 204. In step S705, the output value Vout2 of the AD converter 203 at that time is stored in the memory 206.

  In step S706, it is determined whether the counter variable i is 2 or more. If the counter variable i remains 1, the process proceeds to step S707. If the counter variable i is 2 or more, Vout3 is all resistance-measurement solder balls 102b. , The step of recording Vout3 is omitted. That is, step S707 and step S708 described later are omitted.

  In step S707, the wiring selection switch 603b is set to C and the potential selection switch 603a is set to C by the control signal of the control unit 205 of the microcontroller 204. In step S708, the output value Vout3 of the AD converter 203 at that time is recorded in the memory 206. In this embodiment, Vout1, Vout2, and Vout3 may be stored in any order.

  In step S709, the resistance value calculation unit 207 of the microcontroller 204 calculates the resistance value Rr1 of the resistance measurement solder ball 102b1, and the resistance change calculation unit 208 calculates the resistance with the initial resistance value Rr01 of the resistance measurement solder ball 102b1. A change ΔRr1 is calculated.

  In step S710, the resistance change ΔRr1 and the counter variable i are stored in the memory 206. The resistance calculation process and the initial resistance value storage process at this time are the same as those described with reference to the flowchart of FIG.

  In step S711, the resistance change ΔRr1 is compared with the resistance change allowable value stored in the memory 206 in advance. If the resistance change ΔRr1 is within the resistance change allowable value, in step S712, the counter variable i is incremented to measure the resistance value of the next resistance-measured solder ball 102b2, and the process proceeds to step S713, where the resistance change ΔRr1 is the resistance change. If it is not within the allowable value for change, the process proceeds to step S714.

  In step S713, the above processing is repeated for the resistance measuring solder balls 102b2, 102b3, and 102b4, that is, until the counter variable i becomes 4. When the resistance values of all the resistance measurement solder balls 102b1, 102b2, 102b3, and 102b4 are measured, the counter variable i becomes 5. Therefore, 1 is substituted for i and the above processing is repeated.

  In step S714, if the resistance change ΔRr in any of the resistance measurement solder balls 102b1, 102b2, 102b3, 102b4 is equal to or greater than the resistance change allowable value recorded in advance in the memory 206, the connection is made. An abnormality detection signal is output.

  In the above description, the case where the resistance measurement solder balls 102b1, 102b2, 102b3, and 102b4 are four positions has been described as an example. However, by increasing the number of wiring selection switches 603b and potential selection switches 603a, an arbitrary number of It is possible to record the resistance value of the resistance-measured solder ball 102b and detect a connection abnormality. Further, although the resistance value of the resistance-measured solder ball 102b was measured from 102b1 to 102b4 in order, it is not always necessary to be in this order.

  As described above, according to the connection abnormality detection device of the second embodiment, which resistance measurement solder ball 102b is measured by recording the counter variable i in the memory 206 in step S710 of FIG. This is an advantage that the failure location can be specified at the time of acceptance inspection. Further, if the resistance change ΔRr is recorded, it is possible to refer to the resistance change of the other resistance-measured solder ball 102b as well as the connection abnormality portion as a profile, which has an advantage that is useful when investigating the cause of the failure.

  In the above description, the voltage between the resistance measurement solder balls 102b1, 102b2, 102b3, 102b4 and the constant voltage source 105 is the same as the resistance measurement solder balls 102b1, 102b2, 102b3, 102b4 and the wiring selection switch 603b. Although the configuration for extracting from the voltages V11, V12, V13, and V14 has been described, the voltage V1 between the wiring selection switch 603b and the constant voltage source 105 may be extracted as shown in FIG. Thus, there is an advantage that the potential selection switch 603a can be reduced, and this is effective when the accuracy is sufficient to prevent the temperature change or aging change of the internal resistance of the wiring selection switch 603b.

Embodiment 3 FIG.
Next, a connection abnormality detection apparatus according to Embodiment 3 of the present invention will be described. FIG. 9 is a configuration diagram illustrating the connection abnormality detection device according to the third embodiment, and the same parts as those in FIG. 3 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 9, in the connection abnormality detection device according to the third embodiment, a voltage drop resistor 901 is inserted between a solder ball resistor 111 and a constant voltage source 105. The voltage V1 at the point where the solder ball resistor 111 and the voltage drop resistor 901 are connected and the voltages V2 and V3 across the reference resistor 106 are measured by the method described later. In this embodiment, by inserting the voltage drop resistor 901, the potential of the voltage V1 is lowered, and the amplifier 202 is not saturated even if the constant voltage source 105 and the power source of the amplifier 202 are shared. That is, a power supply circuit for generating the voltage of the constant voltage source 105 is not necessary. In this case, the formula 1 becomes the following formula 9.

  Here, R is a resistance value of the voltage drop resistor 901, and ΔR is a resistance value error of the voltage drop resistor 901. Further, R is a known design value, and ΔR is an unknown value due to a resistance value error due to element variation, temperature change, and secular change. If the above equation 9 is arranged into a term including the measurement resistance r and a term not including it, the following equation 10 is obtained.

  From Equation 10, it can be seen that the voltage Vout recorded in the memory 206 of the microcontroller 204 is expressed by a linear expression of the measurement resistor r even when the voltage drop resistor 901 is added. Therefore, the resistance value Rr of the resistance-measured solder ball 102b can be accurately measured by the same calculation formula as the formula 8. At this time, accuracy is not required for the voltage drop resistor 901.

  The configuration of the connection abnormality detection device according to the third embodiment can also be applied to the connection abnormality detection device according to FIG. 6 described in the second embodiment. In this case, for example, if the voltage drop resistor 901 is inserted between the wiring selection switch 603b and the constant voltage source 105, one additional voltage drop resistor 901 may be added. In addition, the internal resistance of the wiring selection switch 603b is an error of the voltage drop resistor 901 that does not require accuracy, and thus does not affect the calculation result.

  Moreover, it is also possible to apply to the connection abnormality detection apparatus according to FIG. 8 described in the second embodiment. In this case, for example, if a voltage drop resistor 901 is inserted between the potential measurement point V1 and the constant voltage source 105, the same effect as described above can be obtained.

Embodiment 4 FIG.
Next, a connection abnormality detection apparatus according to Embodiment 4 of the present invention will be described. FIG. 10 is a block diagram for explaining a connection abnormality detection device according to the fourth embodiment. The same parts as those in FIG. 3 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 10, in the connection abnormality detection device according to the fourth embodiment, a current conduction switch 1001 that is a current conduction means is added between the reference resistor 106 and the common potential 107. The current conduction switch 1001 is controlled by a control signal from the control unit 205 of the microcontroller 204 and is turned on when measuring the resistance value Rr of the solder ball for resistance measurement. By adopting this embodiment, current flows only when measuring the resistance value Rr of the solder ball for resistance measurement, so that current consumption can be reduced. For example, if the current conduction switch 1001 is turned on and the initial check is performed only when the power supply of the electronic device in which the present invention is installed is turned on and turned off after the connection abnormality is determined, the current is consumed only at the time of the initial check. .

  If the current conduction switch 1001 is turned OFF when, for example, the measurement voltages Vout1, Vout2, and Vout3 output from the AD converter 203 are stored in the memory 206, the voltage measurement point V1 from the constant voltage source 105 in the subsequent processing. , V2 and V3, the current does not flow in the path to the common potential 107, and as a result, the current consumption when detecting the connection abnormality of the solder ball for resistance measurement can be reduced.

  Further, the current conduction switch 1001 may be turned ON only when measuring the voltages at the three voltage measurement points V1, V2, and V3. At this time, when the measured voltages Vout1, Vout2, and Vout3 output from the AD converter 203 are stored in the memory 206 from the register of the AD converter 203, the common potential passes from the constant voltage source 105 through the voltage measuring points V1, V2, and V3. No current flows in the path to 107, and a further effect of reducing current consumption can be obtained.

  In this embodiment, the current conduction switch 1001 is inserted between the reference resistor 106 and the common potential 107. However, the current conduction switch 1001 may be inserted between the resistance measurement solder ball 111 and the constant voltage source 105. Similar effects can be obtained.

  In addition, even when this embodiment is used in combination with the second embodiment or the third embodiment, the same effect can be obtained. In the case of the second embodiment, if the current conduction switch 1001 is inserted between the constant voltage source 105 and the wiring selection switch 603b in FIG. 6, only one current conduction switch 1001 is required and the ON resistance is not required to be accurate. It can be included in the voltage error of the constant voltage source 105.

Embodiment 5 FIG.
Next, a connection abnormality detection apparatus according to Embodiment 5 of the present invention will be described. In the embodiments described so far, the embodiment in which the solder ball 102c for wiring extraction is in the central region of the semiconductor package 101 has been described. In the connection abnormality detection device according to the fifth embodiment, as shown in FIG. 11, solder balls for wiring removal 102 c are provided near the corners of the semiconductor package 101. FIG. 11 corresponds to FIG.

  According to the present embodiment, it is possible to assign a solder ball near the center having theoretically high connection reliability to the signal solder ball 102a. In this case, it is impossible to measure the resistance value Rr1 of the resistance-measured solder ball 102b alone, but the solder connection failure near the corner of the semiconductor package 101 is caused by the resistance value Rr1 of the resistance-measurement solder ball 102b alone and the solder for taking out the wiring. This can be detected as an increase in series resistance with the resistance value Rr2 of the ball 102c.

  FIG. 12 is a configuration diagram for calculating the resistance value of each resistance measurement solder ball 102b using a plurality of resistance measurement solder balls 102b near the corner of the semiconductor package 101. FIG. A plurality of resistance measurement solder balls 102 b 1, 102 b 2, 102 b 3, 102 b 4 are arranged near the corners of the semiconductor package 101. The resistance measurement solder balls 102 b 1, 102 b 2, 102 b 3 and 102 b 4 are connected by the IC internal wiring 104.

  The plurality of resistance measurement solder balls 102b1, 102b2, 102b3, and 102b4 are each a first wiring selection switch 1202 as a first wiring selection means and a second wiring as a second wiring selection means by a circuit board wiring 1201. It is connected to the selection switch 1203. The first wiring selection switch 1202 is connected to the constant voltage source 105, and the second wiring selection switch 1203 is connected to the reference resistor 106. By switching the first wiring selection switch 1202 and the second wiring selection switch 1203, the combined resistance value of two different resistance-measured solder balls 102b is calculated.

  The microcontroller 204 includes a resistance measurement solder ball 102b to be measured and a resistance value selection unit 1204 that selects a combined resistance value related to the resistance, and each resistance measurement solder ball 102b1 and 102b2 from the selected combined resistance value. , 102b3 and 102b4, a resistance value separation unit 1205 for adding resistance values is added. The configuration other than the above is the same as in FIG. 3, and the resistance value between V1 and V2 is calculated with high accuracy from the three voltage measurement points V1, V2, and V3.

  Next, the principle of obtaining the resistance values of the respective resistance-measured solder balls 102b1, 102b2, 102b3, 102b4 from the measured resistance values will be described.

First, three solder balls including the resistance measurement solder ball 102b to be measured are selected (for example, 102b1, 102b2, and 102b3 are selected). When the resistance value of the resistance measurement solder ball 102b1 is Rr1, the resistance value of the resistance measurement solder ball 102b2 is Rr2, and the resistance value of the resistance measurement solder ball 102b3 is Rr3, the first wiring selection switch 1202 and the second wiring The combined resistance value Rr12 measured with the selection switch 1203 set to D2 and E1, respectively, is given by the following equation 11.
Rr12 = Rr1 + Rr2 + ron (Formula 11)
Here, ron is an error between the internal resistance of the first wiring selection switch 1202 and the internal resistance of the second wiring selection switch 1203.

Similarly, the combined resistance values Rr23 and Rr31 measured by setting the first wiring selection switch 1202 and the second wiring selection switch 1203 to D3 and E2, and D1 and E3, respectively, are expressed by the following expressions 12 and 13. become.
Rr23 = Rr2 + Rr3 + ron (Formula 12)
Rr31 = Rr3 + Rr1 + ron (Formula 13)
When the resistance values Rr1, Rr2, and Rr3 of the resistance-measured solder ball 102b1 are obtained by using the equations 11, 12, and 13, the following equations 14, 15, and 16 are obtained.
Rr1 = (Rr12−Rr23 + Rr31 + ron) / 2 (Formula 14)
Rr2 = (Rr23−Rr31 + Rr12 + ron) / 2 (Formula 15)
Rr3 = (Rr31−Rr12 + Rr23 + ron) / 2 (Formula 16)

  Regarding the error ron of the internal resistance, for example, the first wiring selection switch 1202 is set to D1, the second wiring selection switch 1203 is set to E1, and the resistance measurement solder ball 102b and the IC internal wiring 104 are not passed through. It can be determined by measuring the value. Further, the resistance value Rr4 of the remaining resistance-measured solder balls 102b4 is obtained as follows.

That is, when the first wiring selection switch 1202 is set to any one of D1, D2, and D3 (for example, D3) and the second wiring selection switch 1203 is set to E4, the resultant combined resistance value R34 is expressed by the following equation (17). It becomes.
Rr34 = Rr3 + Rr4 + ron (Formula 17)
In the above equation 17, since R34 has been calculated for both the measured value, Rr3 and ron, the resistance value Rr4 of the resistance measurement solder ball 102b4 is obtained by the following equation 18.
Rr4 = Rr34-Rr3-ron (Formula 18)

  Next, the operation of the connection abnormality detection device according to the fifth embodiment will be described with reference to the flowcharts of FIGS. 13 and 14. In this flowchart, the resistance measurement solder balls 102b4 are calculated after the resistance values of the resistance measurement solder balls 102b1, 102b2, 102b3 are calculated for the four resistance measurement solder balls 102b1, 102b2, 102b3, 102b4. Show. Also, FIG. 12 will be referred to for explaining the operation.

  First, in step S1301, the first wiring selection switch 1202 is set to D1, and the second wiring selection switch 1203 is set to E2.

  In step S1302, the combined resistance value Rr12 is calculated and stored in the memory 206 of the microcontroller 204. The calculation method of the combined resistance value Rr12 is the same as that in steps S501 to S507 in the flowchart of FIG.

  Next, in step S1303, the first wiring selection switch 1202 is set to D2, and the second wiring selection switch 1203 is set to E3.

  In step S1304, the combined resistance value Rr23 is calculated and stored in the memory 206 of the microcontroller 204.

  Similarly, in step S1305, the first wiring selection switch 1202 is set to D3, and the second wiring selection switch 1203 is set to E1.

  In step S1306, the combined resistance value Rr31 is calculated and stored in the memory 206 of the microcontroller 204.

  In step S1307, the first wiring selection switch 1202 is set to D3, and the second wiring selection switch 1203 is set to E4.

  In step S1308, the combined resistance value Rr34 is calculated and stored in the memory 206 of the microcontroller 204.

  In step S1309, the first wiring selection switch 1202 is set to D1, and the second wiring selection switch 1203 is set to E1.

  In step S1310, the error ron of the internal resistance is calculated and stored in the memory 206 of the microcontroller 204.

  In step S1311, the combined resistance values Rr12, Rr23, and Rr31 stored in the memory in the above processing are selected by the resistance value selection unit 1204, and the combined resistance values Rr12, Rr23, Rr31, and the internal resistance error ron are used to calculate the above-described Expressions 14 and 15. According to Equation 16, the resistance values Rr1, Rr2, and Rr3 of the respective resistance measurement solder balls 102b1, 102b2, and 102b3 are calculated and stored in the memory 206.

  In step S1312, the calculated combined resistance value Rr34 and resistance value Rr3 are selected by the resistance value selection unit 1204, and the combined resistance value Rr34, resistance value Rr3, and error ron of the internal resistance are used to measure the resistance-measured solder ball 102b4 according to the above equation 18. The resistance value Rr4 is calculated.

  The processing after step S1313 is to calculate a resistance change ΔRr and compare it with the initial resistance value Rr0 to determine a connection abnormality. Since this is the same as the processing from step S508 to step S513, the description is omitted.

  In the above description, which resistance measurement solder ball 102b is calculated in which order may be determined in advance, or may be dynamically determined by the resistance value selection unit 1204.

  In the present embodiment, four examples of the resistance measurement solder balls 102b are shown. However, by increasing the number of the first wiring selection switches 1202 and the second wiring selection switches 1203, five or more resistances are measured. The resistance of the measurement solder ball 102b can also be measured. Further, the order of obtaining the resistance values of the plurality of resistance-measured solder balls 102b may be any order. Furthermore, the first wiring selection switch 1202 and the second wiring selection switch 1203 can be switched as long as they pass through the two resistance-measured solder balls 102b for measuring the resistance value (for example, the first wiring selection switch). 1202 and the second wiring selection switch 1203 are the same when D1 and E2, and when D2 and E1).

  Further, in this embodiment, although calculation processing is increased to obtain each of the resistance values of the plurality of resistance-measured solder balls 102b with high accuracy, a solder ball near the center having a high connection reliability is theoretically taken out. There is no need to assign to the solder ball for signal 102c, and it can be assigned to the solder ball for signal 102a.

  As described above in detail, according to the connection abnormality detection device according to each embodiment of the present invention, it is caused by the influence of variation of electronic parts constituting the circuit for detecting the solder connection abnormality, temperature change, and aging. Therefore, the resistance value of the solder connection portion can be measured with high accuracy. Moreover, the connection abnormality of a solder connection part can be detected early and correctly by the result.

  In particular, when the connection abnormality detection device according to each embodiment of the present invention is used in an in-vehicle electronic device that requires high reliability, it is possible to detect a connection abnormality in a severe usage environment at an early stage. , Reliability can be improved.

  By the way, although the example about the semiconductor package which has a solder ball was shown in each said embodiment, this invention can anticipate the same effect also in the semiconductor package using a pin member, a gull-wing-type lead, or a J-type lead.

  Further, although the resistance measurement method described above has been described for measuring the resistance value of the solder connection portion, it goes without saying that it can also be used for the resistance measurement of other things.

  The connection abnormality detection device according to the present invention and a vehicle-mounted electronic device using the device can be used to detect a connection abnormality of a solder connection portion in the vehicle-mounted electronic device.

It is a principle block diagram of this invention. It is a block diagram explaining the connection abnormality detection apparatus which concerns on Embodiment 1. FIG. It is the equivalent circuit of FIG. 4 is a general configuration example of an amplifier shown in FIG. 3. 4 is a flowchart for explaining the operation of the connection abnormality detection device according to the first embodiment. It is a block diagram explaining the connection abnormality detection apparatus which concerns on Embodiment 2. FIG. 10 is a flowchart for explaining the operation of the connection abnormality detection device according to the second embodiment. It is a block diagram explaining the other example of the connection abnormality detection apparatus which concerns on Embodiment 2. FIG. It is a block diagram explaining the connection abnormality detection apparatus which concerns on Embodiment 3. FIG. It is a block diagram explaining the connection abnormality detection apparatus which concerns on Embodiment 4. It is a principle block diagram of the connection abnormality detection apparatus which concerns on Embodiment 5. It is a block diagram explaining the connection abnormality detection apparatus which concerns on Embodiment 5. FIG. 10 is a flowchart for explaining the operation of the connection abnormality detection device according to the fifth embodiment. 10 is a flowchart for explaining the operation of the connection abnormality detection device according to the fifth embodiment.

Explanation of symbols

101 Semiconductor Package 102a Signal Solder Connection 102b, 102b1, 102b2, 102b3, 102b4 Resistance Measurement Solder Connection 102c Wiring Extraction Solder Connection 103 Circuit Board 104 IC Internal Wiring 105 Constant Voltage Source 106 Reference Resistance 107 Common Potential 108 Voltage Measurement unit 109 Resistance value calculation unit 110 Abnormality determination unit 111, 1101 Solder connection unit resistance 201, 603a, 603b, 1202, 1203 Switch 202 Amplifier 203 AD converter 204 Microcontroller 205 Control unit 206 Memory 207 Resistance value calculation unit 208 Resistance change Calculation unit 209 Abnormality determination unit 401 Operational amplifier 402, 403 Resistor 601, 602, 1201 Circuit board wiring 603a Potential selection switch 603b Wiring selection switch 901 Voltage drop resistor 1201 Road board wiring 1202 first wire selection switch 1203 second wire selection switch 1204 resistance value selector 1205 resistance separation unit

Claims (45)

A connection abnormality detection device for detecting a connection abnormality of a solder connection portion between a semiconductor package mounted on a circuit board and the circuit board,
The solder connection portion includes a resistance measurement solder connection portion connected to a constant voltage source, and a wiring connection solder connection portion connected to the resistance measurement solder connection portion by an internal wiring of the semiconductor package,
A reference resistance having a known resistance value connected to the solder connection portion for wiring extraction, and
When the connection point between the resistance measurement solder connection part and the constant voltage source is V1, one end of the reference resistor is V2, and the other end of the reference resistor is V3, the voltage of V1 and the voltage of the V2; And voltage measuring means for measuring the voltage of V3, respectively.
A resistance value calculating means for calculating a resistance value of the resistance-measured solder connection portion using the voltage of V1, the voltage of V2, and the voltage of V3 measured by the voltage measuring means;
An abnormality determination means for determining a connection abnormality based on a change in resistance value of the resistance measurement solder connection portion calculated by the resistance value calculation means;
A connection abnormality detection device comprising:   2. The resistance measurement solder connection portion is provided at a position farther from the center of the semiconductor package than a corner region of the semiconductor package or a signal solder connection portion of the semiconductor package. Connection abnormality detection device.   3. The wiring connection solder connection portion is provided in a central region of the semiconductor package or in a position closer to the center of the semiconductor package than the resistance measurement solder connection portion. The connection abnormality detection device described.   The connection abnormality detection device according to claim 1, wherein the wiring connection solder connection portion connects a plurality of solder connection portions. The voltage measuring means includes
Voltage selection means for selecting the voltage of V1, the voltage of V2, and the voltage of V3;
Amplifying means for amplifying the voltage selected by the voltage selecting means;
AD conversion means for digitally converting the voltage amplified by the amplification means;
A control unit for controlling selection of a voltage by the voltage selection unit;
The connection abnormality detection device according to any one of claims 1 to 4, further comprising:   The connection abnormality detection device according to claim 5, wherein the voltage selection unit includes a switch that is switched by a control signal.   The connection abnormality detection device according to claim 6, wherein the control signal is controlled by the control unit. The resistance value calculating means includes
A memory for storing the measured voltage;
A resistance value calculation unit for calculating a resistance value of the resistance measurement solder connection unit;
The connection abnormality detection device according to any one of claims 1 to 7, further comprising: The resistance value calculation unit is configured such that when the voltage V1 is Vout1, the voltage V2 is Vout2, the voltage V3 is Vout3, and the resistance value of the reference resistance is Rref, the resistance of the resistance measurement solder connection unit The connection abnormality detection device according to claim 8, wherein the value Rr is calculated as follows.
Rr = Rref (Vout1-Vout2) / (Vout2-Vout3) The abnormality determining means includes
A resistance change calculation unit for calculating a resistance change of the resistance measurement solder connection part;
An abnormality determining unit for determining a connection abnormality based on the resistance change calculated by the resistance change calculating unit;
A memory for recording an initial resistance value of the resistance measurement solder connection portion;
The connection abnormality detection device according to any one of claims 1 to 9, further comprising:   The connection according to claim 10, wherein the resistance change calculation unit calculates a resistance change of the resistance measurement solder connection part by subtracting an initial resistance value from a resistance value of the resistance measurement solder connection part. Anomaly detection device.   The connection abnormality detection device according to claim 11, wherein the initial resistance value is a resistance value of the resistance measurement solder connection portion that is measured in advance and stored in a memory.   The connection according to claim 11, wherein the initial resistance value is a resistance value of the resistance-measured solder connection portion measured when power is first applied to an electronic device including the circuit board. Anomaly detection device.   The initial resistance value is compared with an initial resistance allowable value recorded in the memory, and when the initial resistance value exceeds the initial resistance allowable value, a connection abnormality detection signal is output. The connection abnormality detection device according to 13.   The abnormality determination unit compares the resistance change with a resistance change allowable value recorded in the memory, and outputs a connection abnormality detection signal when the resistance change exceeds the resistance change allowable value. The connection abnormality detection device according to claim 10. The resistance measurement solder connection part is composed of a plurality,
Wiring selection means for selecting connection between each of the resistance measurement solder connection portions of the plurality of resistance measurement solder connection portions and the constant voltage source;
Voltage selection means for selecting a voltage at a connection point between the wiring selection means and each of the resistance measurement solder connection portions and a voltage at both ends of the reference resistance;
The connection abnormality detection device according to any one of claims 1 to 4, further comprising: The resistance measurement solder connection part is composed of a plurality,
Wiring selection means for selecting connection between each of the resistance measurement solder connection portions of the plurality of resistance measurement solder connection portions and the constant voltage source;
Voltage selection means for selecting a voltage at a connection point between the wiring selection means and the constant voltage source, and respective voltages at both ends of the reference resistor;
The connection abnormality detection device according to any one of claims 1 to 4, further comprising:   The connection abnormality detection device according to claim 16 or 17, wherein the wiring selection means is configured by a switch that is switched by a control signal.   The connection abnormality detection device according to any one of claims 1 to 18, wherein a voltage drop resistor is provided between the resistance measurement solder connection portion and the constant voltage source.   The connection abnormality detection device according to any one of claims 16 to 18, wherein a voltage drop resistor is provided between the wiring selection unit and the constant voltage source.   21. The connection abnormality detection device according to claim 1, further comprising a current conduction means provided between the reference resistance and a common potential of the connection abnormality detection device.   The connection abnormality detection device according to any one of claims 1 to 20, wherein a current conduction unit is provided between the resistance measurement solder connection part and the constant voltage source.   The connection abnormality detection device according to claim 21 or 22, wherein the current conduction means is configured by a switch that is switched by a control signal.   The connection abnormality detection device according to claim 23, wherein the control signal is controlled by the control unit.   25. The connection abnormality detection device according to claim 24, wherein the control unit controls the control signal so that the switch is turned on at the time of resistance measurement of the resistance measurement solder connection unit.   26. The connection abnormality detection device according to claim 25, wherein the resistance measurement is a power-on time of the electronic device.   The control signal is controlled so that the switch is turned on when any one of the voltage of V1, the voltage of V2, and the voltage of V3 is measured. Connection abnormality detection device.   The control signal is controlled to turn off the switch after the voltage V1, the voltage V2, or the voltage V3 is stored in the memory. The connection abnormality detection device according to claim 24.   23. The connection abnormality detection device according to claim 22, wherein a voltage drop resistor is provided between the current conducting means and the constant voltage source.   The connection abnormality detection device according to claim 1, wherein the wiring connection solder connection portion is in a corner region of the semiconductor package. A connection abnormality detection device for detecting a connection abnormality of a solder connection portion between a semiconductor package mounted on a circuit board and the circuit board,
The solder connection portion includes at least three resistance measurement solder connection portions connected to a constant voltage source,
A reference resistance with a known resistance value connected to the resistance measurement solder connection part, and
Current path selection means for selecting a current path that passes through at least two of the plurality of resistance-measured solder connection parts;
When the connection point between the constant voltage source and the resistance measurement solder connection part is V1, one end of the reference resistor is V2, and the other end of the reference resistor is V3, the voltage of V1 and the voltage of the V2; And voltage measuring means for measuring the voltage of V3, respectively.
A resistance value calculating means for calculating a combined resistance value between V1 and V2 using the voltage of V1 and the voltage of V2 measured by the voltage measuring means and the voltage of V3;
Resistance value separation means for calculating a resistance value of the resistance measurement solder connection using a combined resistance value between V1 and V2,
An abnormality determination means for determining an abnormality of connection based on a change in the resistance value of the resistance-measured solder connection part.   32. The connection abnormality detection device according to claim 31, wherein the plurality of resistance measurement solder connection portions are connected to each other by IC internal wiring of the semiconductor package. The current path selection means includes
First wiring selection means inserted between the plurality of resistance measurement solder connection portions and the constant voltage source;
Second wiring selection means inserted between the plurality of resistance measurement solder connection portions and the reference resistance;
The connection abnormality detection device according to claim 31, comprising:   34. The connection abnormality detection device according to claim 33, wherein the first wiring selection unit and the second wiring selection unit are configured by a switch that is switched by a control signal. The resistance value separating means includes
A combined resistance value of a plurality of paths selected by the current path selection unit and calculated by the resistance value calculation unit, and an internal resistance error between the first wiring selection unit and the second wiring selection unit are stored. Memory,
A resistance value selector for selecting one or more combined resistance values from the combined resistance values of the plurality of paths;
A resistance value separation unit for calculating a resistance value of each of the plurality of resistance measurement solder connection parts from a combined resistance value of the plurality of paths;
The connection abnormality detection device according to claim 31, comprising:   The resistance selection unit selects three resistance measurement solder connection portions with unknown resistance values from the plurality of resistance measurement solder connection portions, and is configured by the three resistance measurement solder connection portions from the previous memory. 36. The connection abnormality detection device according to claim 35, wherein a combined resistance value of three different paths is selected.   The connection abnormality detection according to claim 35 or 36, wherein the error of the internal resistance is a combined resistance value of a path that does not pass through the resistance measurement solder connection selected by the current path selection means. apparatus. The resistance value separation unit has three resistance measurement solder connection portions with unknown resistance values when the combined resistance value of the three different paths is Rr12, Rr23, Rr31, and the error of the internal resistance is ron. The connection abnormality detection device according to any one of claims 35 to 37, wherein Rr1, Rr2, and Rr3 are calculated as follows:
Rr1 = (Rr12−Rr23 + Rr31 + ron) / 2
Rr2 = (Rr23−Rr31 + Rr12 + ron) / 2
Rr3 = (Rr31-Rr12 + Rr23 + ron) / 2   The resistance value selection unit selects one resistance measurement solder connection unit with an unknown resistance value, and a resistance measurement solder connection unit with an unknown resistance value from the memory and a resistance measurement solder connection with a known resistance value. 36. The connection abnormality detection device according to claim 35, wherein a combined resistance value of a route passing through the section is selected. The resistance value separation unit has Rr45 as the combined resistance value, Rr4 as the resistance value of the resistance-measurement solder connection unit whose resistance value is known, and the internal of the first wiring selection unit and the second wiring selection unit. 40. The connection abnormality detection device according to claim 39, wherein, when the resistance error is ron, the resistance value Rr5 of the resistance-measured solder connection portion whose resistance value is unknown is calculated as follows.
Rr5 = Rr45-ron   The connection abnormality detection device according to any one of claims 1 to 40, wherein the solder connection portion is formed of a solder ball.   42. The connection abnormality detection device according to claim 41, wherein the semiconductor package is a ball grid array.   41. The connection abnormality detection method according to any one of claims 1 to 40, wherein the solder connection portion includes a pin member.   The connection abnormality detection device according to any one of claims 1 to 40, wherein the solder connection portion includes a gull wing-shaped lead or a J-type lead.   45. A vehicle-mounted electronic device using the connection abnormality detection device according to any one of claims 1 to 44 for a vehicle-mounted electronic device mounted on a vehicle.

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