JP5347460B2 - Integrated circuit device for secondary battery protection and inspection method for integrated circuit device for secondary battery protection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an integrated circuit device for protection of a secondary battery, which can stabilize clock in inspection, and a method of inspecting the integrated circuit device for protection of the secondary battery. <P>SOLUTION: It has an internal oscillator 10, which generates clock pulses in operation, a delay time generating means 20, which generates a delay time for each internal circuit 40-120, based on inputted clock pulses, a delay time shortening terminal DS, into which clock pulse in inspection can be inputted from outside, and a connection switching means SW, which connects the internal oscillator 10 with the delay time generating means 20, in usual operation, so that the delay time may be generated, based on the clock pulse in operation, and connects the delay time shortening terminal DS with the delay time generating means 20, in inspection of electric performance, so that the delay time may be generated, based on the clock pulses in inspection. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an integrated circuit device for secondary battery protection of a secondary battery such as a lithium ion battery or a lithium polymer battery, and an inspection method for the integrated circuit device for secondary battery protection, in particular, based on an input clock pulse, The present invention relates to a secondary battery protection integrated circuit device having a delay time generating means for generating a delay time of each internal circuit, and a method for inspecting a secondary battery protection integrated circuit device.

  2. Description of the Related Art Conventionally, a charge / discharge protection circuit that detects overcharge, overdischarge, or overcurrent of a secondary battery and protects the secondary battery from overcharge, overdischarge, or overcurrent, comprising a constant current inverter and a capacitor An internal oscillation circuit composed of a ring oscillator with a plurality of delay elements connected in a closed loop, a delay circuit for determining a delay time upon detection of overcharge, overdischarge, or overcurrent composed of a counter circuit, and a test circuit Means to fix the potential of the test terminal at low level or high level, and increase the constant current of the constant current source constituting the constant current inverter of the delay element when the test terminal is fixed at high level or low level A technique having a delay time shortening means for shortening the delay time of the delay circuit is known (see, for example, Patent Document 1).

When a ring oscillator is used as the internal oscillator as in Patent Document 1, the internal oscillator oscillates at a cycle that can be simply expressed as IT = CV. That is, it can be seen that by increasing the current I, the period T decreases and oscillation occurs at a high frequency.
JP 2001-268810 A

  However, in the configuration described in Patent Document 1 described above, as can be seen from the equation IT = CV, the dependency of the voltage applied to the internal oscillator, the variation in the drive current, the variation in the capacitance value, etc. The frequency varies. For this reason, there has been a problem that the delay time set by dividing by the counter also varies.

  In this format, the drive current is increased to shorten the period T of the internal oscillator, but the increase in drive current also varies, so the speed factor also has a range, and the charge protection circuit IC (Integrated Circuit, integrated circuit) The inspection time of the circuit also needs to have a certain margin, and there is a problem that the inspection time cannot be sufficiently shortened.

  Therefore, the present invention provides an integrated circuit device for protecting a secondary battery and a method for inspecting an integrated circuit device for protecting a secondary battery, which can stabilize a clock at the time of testing and sufficiently shorten the testing time. With the goal.

In order to achieve the above object, an integrated circuit device for protecting a secondary battery (150, 150a, 150b) according to a first invention includes an internal oscillator (10) for generating a clock pulse during operation,
A delay time generating means (20) for generating a delay time of each internal circuit (40-120) based on the inputted clock pulse;
Delay time shortening terminal (DS) that can input clock pulse from the outside during inspection,
During normal operation, the internal oscillator (10) and the delay time generation means (20) are connected so that the delay time is generated based on the operation time clock pulse. Connection switching means (SW) for connecting a delay time shortening terminal (DS) and the delay time generating means (20) so as to generate the delay time based on the clock pulse at the time of inspection;
A shift register (30) connected to the delay time shortening terminal (DS),
The shift register (30) counts the inspection clock pulse input to the delay time shortening terminal (DS),
The connection switching means (SW) connects the delay time shortening terminal (DS) and the delay time generating means (20) when the inspection clock pulses counted by the shift register (30) are a predetermined number or more. It is characterized by connecting .

As a result, clock pulses can be input from the outside during inspection, and in order to reduce the delay time based on this, a stable and accurate clock pulse is input, and this is divided to generate a delay time. The delay time of the internal circuit at the time of inspection can be stabilized. In addition, since a clock pulse is input from the outside, various clock pulses can be input, and a flexible inspection according to the application is possible and an inspection can be appropriately performed on the user side. In addition, it is possible to automatically switch to the inspection mode in which inspection is performed using the inspection clock pulse only by inputting the inspection clock pulse from the outside.

A second invention is an integrated circuit device (150, 150a, 150b) for protecting a secondary battery according to the first invention.
The inspection clock pulse is inputted with a clock pulse having a frequency higher than that of the operation clock pulse to shorten the delay time.

  Thereby, the delay time can be shortened, and since the delay time is based on the clock pulse of the external signal, the delay time can be greatly shortened by using a signal having a sufficiently high frequency.

A third invention is the secondary battery protection integrated circuit device (150a, 150b) according to the first invention, wherein
The internal oscillator (10) is connected to the delay time shortening terminal (DS), and is generated by the internal oscillator (10) when a constant voltage is input instead of the clock pulse at the time of inspection. The delay time is generated using a shortened clock pulse.

  For this reason, for example, when you want to perform inspections using clock pulses from an internal oscillator for comparison, you can perform inspections in the conventional inspection mode, and can perform various inspections including comparisons. It becomes.

The secondary battery protection integrated circuit device (150, 150a, 150b) according to the fourth invention is a secondary battery protection integrated circuit device (150, 150a, 150b) according to any one of the first to third inventions. 150b), which is an inspection method.
The internal oscillation circuit (10) of the secondary battery protection integrated circuit device (150, 150a, 150b) is connected to the delay time shortening terminal (DS) of the secondary battery protection integrated circuit device (150, 150a, 150b). An inspection clock pulse having a frequency higher than that of the generated operating clock pulse is input, and the delay time of the internal circuit (10) of the secondary battery protection integrated circuit device (150, 150a, 150b) is shortened. It is characterized by the inspection of the physical characteristics.

  As a result, the inspection can be performed in a state where the delay time is accurately and greatly shortened.

  Note that the reference numerals in the parentheses are given for easy understanding, are merely examples, and are not limited to the illustrated modes.

  According to the present invention, it is possible to inspect the secondary battery protection integrated circuit in a state where the delay time is stably adjusted.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing an example of the overall configuration of an integrated circuit device 150 for protecting a secondary battery according to a first embodiment to which the present invention is applied. In FIG. 1, the integrated circuit device 150 for protecting a secondary battery according to the first embodiment includes a delay time shortening terminal DS, an internal oscillator 10, a delay time generating means 20, and a switch SW. Moreover, the integrated circuit device 150 for secondary battery protection which concerns on Example 1 is an overcharge detection circuit 40, the overdischarge detection circuit 50, the discharge overcurrent detection circuit 60 as an internal circuit as a related component, The charging overcurrent detection circuit 70, the logic circuits 80 and 120, the level shift circuit 90, the short circuit detection circuit 100, the delay circuit 110, and the overcharger 130 may be provided. In addition, the integrated circuit device for secondary battery protection 150 according to the first embodiment includes the VDD terminal, the VSS terminal, the current detection terminal V−, the charge control terminal COUT, and the discharge control terminal DOUT as terminals. May be. Further, a test time clock pulse supply means 200 connected to the delay time shortening terminal DS is prepared as an externally related component.

  The delay time shortening terminal DS is a terminal to which a clock pulse can be input from the outside when the internal circuits 40 to 130 of the secondary battery protection integrated circuit device 150 according to the present embodiment are inspected. In the integrated circuit device for secondary battery protection 150 according to the present embodiment, the internal circuits 40 to 130 are inspected not using clock pulses generated from the internal oscillator 10 but using clock pulses generated externally. . The delay time shortening terminal DS is used for inputting a clock pulse generated outside the integrated circuit device 150 for protecting the secondary battery when the electrical characteristics of the internal circuits 40 to 130 are inspected. Functions as a terminal. Therefore, when the secondary battery protection integrated circuit device 150 is inspected, the delay time shortening terminal DS is connected to the output line of the external inspection clock pulse supply means 200, and the inspection time clock pulse is input from the connected output line. Will be.

  The clock pulse supply means 200 at the time of inspection is provided outside the integrated circuit device for secondary battery protection 150 according to the present embodiment, and at the time of inspection at the delay time shortening terminal DS when the integrated circuit device for secondary battery protection 150 is inspected. This is voltage pulse supply means for supplying clock pulses. The inspection clock pulse output from the inspection clock pulse supply means 200 may be a clock pulse having a higher frequency than the clock pulse during normal operation, and the total time is shortened when the same number of pulses are accumulated. It is preferable to output such a clock pulse at the time of inspection. Thereby, the delay time of each internal circuit 40-120 at the time of a test | inspection can be shortened. For example, if the clock pulse frequency at the time of inspection is 4 [kHz], the clock pulse at the time of inspection is set to a value higher than that, for example, 5 [kHz] or 6 [kHz]. Also good. Even when the frequency of the clock pulse is increased in this way, the inspection clock pulse can be supplied using the inspection clock pulse supply means 200 by an external stable power supply, so that a stable pulse can be supplied.

  The internal oscillator 10 generates a clock pulse when the integrated circuit device 150 for secondary battery protection is used and a normal secondary battery protection operation is performed. As the internal oscillator 10, for example, a conventionally used ring oscillator or the like may be applied, and an appropriate type of oscillating means may be applied depending on the application.

  The internal oscillator 10 is not electrically connected to the delay time shortening terminal DS. Conventionally, since the inspection is performed using the clock pulse generated by the internal oscillator 10 at the time of the inspection, the internal oscillator 10 and the delay time shortening terminal DS are connected, and the voltage for shortening the delay time is the delay time shortening terminal. It was input to the internal oscillator 10 via DS. However, in the integrated circuit device for secondary battery protection 150 according to the present embodiment, the internal oscillator 10 supplies a clock pulse only during normal operation, so there is no need to reduce the delay time. Not connected to DS.

  The delay time generation means 20 is a means for generating a delay time for each of the internal circuits 40 to 120 based on the input clock pulse. Various means may be applied to the delay time generation means 20 as long as the delay time can be generated from the input clock pulse. For example, a counter may be applied.

  The generation of the delay time by the delay time generation unit 20 may be performed, for example, by dividing a clock pulse. For example, when the frequency of the input clock pulse is f, conversion to f / n frequency is performed, and conversion to lower the clock pulse frequency is performed. That is, for example, when the frequency is divided by 2, the frequency of the clock pulse is halved, and when the frequency is divided by 4, the frequency of the clock pulse is ¼. Thereby, the delay time set in each internal circuit 40-120 can be generated and set.

  The switch SW is connection switching means for switching whether the delay time generating means 20 is connected to the delay time shortening terminal DS or to the internal oscillator 10. The integrated circuit device for secondary battery protection 150 according to the present embodiment switches the switch SW to the lower side and connects the delay time generating means 20 and the internal oscillator 10 during normal operation during normal use to connect the internal oscillator 10 to the internal oscillator. The connection is switched so that the operating clock pulse generated by 10 is input to the delay time generating means 20. Further, the secondary battery protection integrated circuit device 150 according to the present embodiment switches the switch SW to the upper side to connect the delay time generating means 20 and the delay time shortening terminal DS at the time of inspection, and at the time of external inspection. The connection is switched so that the inspection time clock pulse is input from the clock pulse supply means 200 to the delay time shortening terminal DS.

  In this way, by adopting a configuration in which the clock pulse input to the delay time generation means 20 can be switched by switching the connection of the switch SW, the inspection clock pulse having a stable frequency is input from the outside during the inspection. During normal operation, an operating clock pulse can be supplied from the internal oscillator 10 independently. Thereby, at the time of inspection, the performance inspection of each of the internal circuits 40 to 130 can be performed using a stable high frequency suitable for the inspection, so that a stable and highly reliable inspection is performed while sufficiently shortening the inspection time. It becomes possible.

  The switch SW may be an analog switch as shown in FIG. 1, and the relay means may be a semiconductor switching element such as a MOS transistor. As long as the switch SW is a connection switching unit that can switch the connection between the delay time generation unit 20 and the clock pulse source, various connection switching units can be applied.

  The delay times of the internal circuits 40 to 120 generated by the delay time generation means 20 are sent to the logic circuits 80 and 120, and when performing various secondary battery protection operations, a predetermined delay time is set for each internal circuit. Set for circuits 40-120.

  Next, other related components will be described.

  The overcharge detection circuit 40 monitors the potential of the VDD terminal, and when the potential of the VDD terminal is equal to or higher than a predetermined overcharge detection voltage and the state continues for a predetermined delay time or longer, a secondary battery (not shown). It is a circuit which detects the overcharge state of. In the overcharge detection circuit 40, for example, a delay time of about 1 [s] is set. At this time, if an inspection is performed after waiting for a delay time of 1 [s], an enormous amount of inspection time is required. An inspection clock pulse having a frequency higher than that of the operating clock pulse generated by the oscillator 10 is input, and this is divided to set a delay time at the time of inspection. Therefore, the inspection of the overcharge detection circuit 40 does not require a delay time of 1 [s], and the inspection can be performed using the shortened delay time.

  The overdischarge detection circuit 50 monitors the potential of the VDD terminal, and detects the overdischarge state of the secondary battery when the potential of the VDD terminal is below a predetermined overdischarge detection voltage for a predetermined delay time or longer. Circuit. In the overdischarge detection circuit 50, for example, a delay time of 20 [ms] may be set. Also in this case, at the time of inspection, the switch SW is switched so that the delay time generation means 20 is connected to the delay time shortening terminal DS, and the delay time shortening terminal DS is at the time of inspection higher than the clock pulse at the time of operation. By inputting the clock pulse, the delay time can be shortened and the overdischarge detection circuit 50 can be inspected. Further, in the overdischarge detection circuit 50, when a charger is connected to the secondary battery and the recovery from the overdischarge state is detected, the overdischarge recovery delay time is set. At the time of inspection, it can be shortened by inputting an inspection time clock pulse to the delay time shortening terminal DS.

  The discharge overcurrent detection circuit 60 detects the discharge overcurrent state of the secondary battery when the voltage detected at the current detection terminal V− is a predetermined discharge overcurrent detection voltage for a predetermined delay time or longer. Is a circuit for detecting Also in the discharge overcurrent detection circuit 60, for example, a delay time of about 6 [ms] is set, and further, a discharge overcurrent return delay time is set when returning from the discharge overcurrent state. By using the inspection clock pulse supplied from the inspection clock pulse supply means 200, a stable inspection can be performed while reducing the inspection time.

  The charge overcurrent detection circuit 70 is a circuit that detects the charge overcurrent state of the secondary battery when the terminal voltage of the current detection terminal V− continues below a predetermined charge overcurrent detection voltage for a predetermined delay time or longer. . The delay time of the charge overcurrent detection circuit 70 may be about 8 [ms], for example. The charge overcurrent detection circuit 70 may also be set with a delay time for returning from the charge overcurrent state, both of which are separated from the clock pulse at the time of inspection input from the delay time shortening terminal DS at the time of inspection. The test is performed in a rounded and shortened state.

  The logic circuit 80 is arithmetic processing means for performing a logical operation and performing control to protect the secondary battery when an overcharge or a charge overcurrent is detected in the overcharge detection circuit 40 or the charge overcurrent detection circuit 70. is there. The delay time generated by the delay time generation means 20 may be set in the logic circuit of the logic circuit 80, for example.

  The level shift circuit 90 is a circuit for converting the voltage level of the output signal of the logic circuit 80 into a voltage level suitable for gate drive of a charge control MOS transistor (not shown) connected to the charge control terminal COUT. .

  The short-circuit detection circuit 100 is a circuit that detects a short-circuit state of the secondary battery when a load short-circuit occurs and the voltage of the current detection terminal V− becomes equal to or higher than a predetermined short-circuit detection voltage. Also in the short circuit detection circuit 100, the delay time at the time of short circuit detection is set. For example, the delay time is set to be extremely shorter than other internal circuits 40 to 80 of about 400 [μs]. Are set separately by the delay time setting circuit 110. The delay time setting circuit 110 is a dedicated delay time setting means for detecting a short-circuit state in the short-circuit detection circuit 100, and sets a short delay time that is 1/10 or less of the other detection circuits 40 to 70.

  The logic circuit 120 is a logic for performing control to protect the secondary battery when overdischarge, discharge overcurrent, or short circuit is detected by the overdischarge detection circuit 50, the discharge overcurrent detection circuit 60, or the short circuit detection circuit 100. It is a calculation means. Specifically, the logic circuit 120 drives and controls a discharge control terminal DOUT to which an external discharge control MOS transistor (not shown) is connected, and discharge control is performed when overdischarge, discharge overcurrent, or short circuit is detected. A logical operation process for outputting a low level signal to the terminal DOUT is performed.

  Note that the delay times of the overdischarge detection circuit 50, the discharge overcurrent detection circuit 60, and the short circuit detection circuit 100 may be set by being incorporated in a logic circuit in the logic circuit 120.

  The overcharger detection circuit 130 monitors the charger voltage between the VDD terminal and the current detection terminal V−, and when this voltage exceeds a predetermined overcharger detection voltage, the overcharger detection circuit 130 is driven to a low level from the charge control terminal COUT. Is a circuit that stops charging. Since the delay time is not set in the overcharger detection circuit 130, there is little functional relevance with the integrated circuit device 150 for secondary battery protection according to the present embodiment.

  As described above, according to the integrated circuit device for secondary battery protection 150 according to the first embodiment, the clock pulse input to the delay time generation unit 20 is externally input from the delay time shortening terminal DS by the switch SW at the time of inspection. By using the clock pulse for inspection supplied from, a stable high frequency clock pulse for inspection can be divided to generate a delay time, and accurate inspection can be performed in a short time. Further, during normal operation, the delay time generating means 20 can be connected to the internal oscillation circuit 10 by the switch SW, and the conventional secondary battery protection operation can be performed.

  Further, conventionally, since the clock pulse output from the internal oscillator 10 could only be used, the user side could not perform an inspection with an arbitrary setting. However, the secondary battery protection integration according to the present embodiment was not possible. According to the circuit device 150, since the clock pulse at the time of inspection can be input from the outside, the user can flexibly perform the inspection using the desired clock pulse at the time of inspection.

  FIG. 2 is a diagram showing an example of the overall configuration of an integrated circuit device for secondary battery protection 150a according to a second embodiment to which the present invention is applied. 2, in the integrated circuit device for secondary battery protection 150a according to the second embodiment, the internal oscillator 10 is not connected to the delay time shortening terminal DS, and the delay time generating means 20 and the internal oscillator 10 or the delay time shortening terminal are not connected. The point that a switch SW is provided as a connection switching means for switching the connection with the DS is the same as in the integrated circuit device for secondary battery protection 150 according to the first embodiment. In the secondary battery protection integrated circuit device 150a according to FIG. 2 of the second embodiment, the shift register 30 connected to the delay time shortening terminal DS is further provided in the secondary battery protection integrated circuit device 150a. This is different from the integrated circuit device 150 for secondary battery protection according to FIG.

  The shift register 30 stores and accumulates the inspection clock pulse input from the delay time shortening terminal DS when the secondary battery protection integrated circuit device 150a is inspected, and the inspection clock pulse has reached a predetermined number of pulses. Sometimes, it is means for outputting an inspection mode signal and switching the connection of the switch SW. That is, the shift register 30 counts the inspection clock pulses output from the external inspection clock pulse supply means 200 and input to the delay time shortening terminal DS, and when the accumulated inspection pulses reach a predetermined number. Recognize that the inspection will be performed. Since the inspection is performed from now on, the switch SW is switched to the upper side, and the connection switching is performed so that the delay time generation unit 20 is connected to the delay time shortening terminal DS.

  The predetermined number of pulses may be any number of pulses that can reliably recognize that the clock pulse supply means 200 for inspection of the delay time shortening terminal is connected. For example, the number of pulses is 5 or more and 30 or less, preferably An arbitrary number of pulses from 10 to 20 may be set as the predetermined number of pulses.

  In addition, the switch switching of the switch SW by the shift register 30 is performed, for example, when the shift register 30 counts the number of high-level input pulses by the clock pulse at the time of inspection and when the predetermined number of pulses is reached, the high-level inspection mode signal The switch SW may be switched to the upper side in response to the high level signal.

  Further, by counting the number of clock pulses at the time of inspection by the shift register 30, for example, even when a constant voltage power source for inspection as in the past is erroneously connected to the delay time shortening terminal DS, the pulse If is not input, since it is not recognized that the inspection is performed by the shift register 30, such a malfunction can be prevented.

  Thus, according to the integrated circuit device for secondary battery protection 150a according to the second embodiment, the inspection time pulse pulse supplying means 200 is connected to the delay time shortening terminal DS from the outside, and the inspection is automatically performed from now on. It is recognized that this will be done, and inspection can be performed promptly. It goes without saying that the secondary battery protection integrated circuit device 150a according to the second embodiment can achieve the same effects as those described in the first embodiment.

  The other constituent elements are the same as those of the integrated circuit device 150 for protecting a secondary battery according to the first embodiment, and therefore, the same reference numerals are given and description thereof is omitted.

  FIG. 3 is a diagram showing an example of the overall configuration of an integrated circuit device 150b for secondary battery protection according to a third embodiment to which the present invention is applied. In FIG. 3, the integrated circuit device 150b for secondary battery protection according to the third embodiment includes a delay time shortening terminal DS, an internal oscillator 10, a delay time generating means 20, and a shift register 30, and includes a delay time shortening terminal. The shift register 30 counts the number of clock pulses at the time of inspection when the detection clock pulse supply means 200 is connected to the DS, and the connection of the switch SW can be switched when the predetermined number is reached. Then, it is the same as that of the integrated circuit device 150a for secondary battery protection which concerns on Example 2 of FIG.

  However, in the secondary battery protection integrated circuit device 150b according to the third embodiment, the secondary battery protection integrated circuit according to the second embodiment is different in that the internal oscillator 10 and the delay time shortening terminal DS are electrically connected. Different from the circuit device 150a. As described above, the internal oscillator 10 and the delay time shortening terminal DS may be constantly connected. When the inspection time pulse supply means 200 is connected to the delay time shortening terminal DS from the outside, and the inspection time pulse is inputted, the shift register 30 can recognize that the inspection will be started, so the connection of the switch SW This is because the connection switching for connecting the delay time shortening terminal DS and the delay time generating means 20 can be performed. As a result, the inspection time pulse supplied from the external inspection time pulse supply means 200 is input to the delay time generation means 20, and the delay time is shortened using a stable high-frequency clock pulse. 40-130 inspections can be performed.

  In the secondary protection integrated circuit device 150b according to the third embodiment of FIG. 3, for example, when a conventional constant voltage power supply is connected to the delay shortening terminal DS, instead of the clock pulse at the time of inspection. As in the prior art, the delay time can be generated based on the shortened clock pulse generated by the internal oscillator 10 and the inspection can be performed. Thereby, for example, in an environment where an accurate and stable clock pulse for inspection is supplied from the external clock pulse supply means 200 for inspection, the function of the integrated circuit device for secondary potential protection 150b according to the present embodiment is used. If the inspection clock pulse supply means 200 is not prepared and the external inspection clock pulse supply means 200 cannot be prepared and the conventional power supply equipment must be used for the inspection, the conventional inspection is performed. It can also be done.

  As described above, in the integrated circuit device for secondary battery protection 150b according to the third embodiment, the inspection clock pulse supply unit 200 can prepare the inspection using the clock pulse supplied from the outside in the normal inspection situation. In a very inspection situation where the inspection clock pulse supply means 200 cannot be prepared, a flexible inspection response is possible in which inspection is performed using a shortened clock pulse according to the conventional method. Needless to say, the same effects as described in the first embodiment can be obtained in the third embodiment.

  Since the other components are the same as those of the integrated circuit devices for secondary battery protection 150 and 150b according to the first and second embodiments, the same reference numerals are given and the description thereof is omitted.

[Reference example]
FIG. 4 is a diagram showing an example of the overall configuration of a conventional secondary battery protection integrated circuit device 250 as a comparative reference example. In FIG. 4, the internal oscillator 10 is connected to the delay time shortening terminal DS and also connected to the delay time generating means 20. Further, the switch SW and the shift register 30 are not provided. Further, a constant voltage power supply 300 is connected to the delay time shortening terminal DS from the outside, and a constant voltage is input to the delay time shortening terminal DS.

  In this configuration, the delay time is shortened by increasing the current I from the relationship IT = CV, thereby shortening the period T of the clock pulse generated by the internal oscillator 10 and increasing the frequency. In the case of this type, the frequency of the internal oscillator 10 varies due to the dependency of the voltage V applied to the internal oscillator 10, the variation of the drive current I, the variation of the capacitance value C, and the like. The delay time generated by frequency division also varies.

  Therefore, as described in the first to third embodiments of the present application, the clock pulse input to the delay time generating means 20 is switched by the switch SW as the connection switching means. By executing the inspection method for generating the delay time by dividing the clock pulse at the time of inspection supplied from the supply means 200, the electrical characteristics can be accurately inspected in a stable state. At that time, the inspection clock pulse input to the delay time shortening terminal DS from the inspection clock pulse supply means 200 has a sufficiently high frequency, at least a frequency higher than the operation clock pulse generated by the internal oscillator 10 during normal operation. By doing so, it is possible to execute an inspection method for performing an inspection with a sufficiently reduced delay time.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

1 is an example of an overall configuration diagram of an integrated circuit device for secondary battery protection 150 according to Example 1. FIG. 6 is an example of an overall configuration diagram of an integrated circuit device for secondary battery protection 150a according to Embodiment 2. FIG. 10 is an example of an overall configuration diagram of an integrated circuit device for secondary battery protection 150b according to Embodiment 3. FIG. It is a whole block diagram of the conventional secondary battery protection integrated circuit device 250 of the comparative reference example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Internal oscillator 20 Delay time generation means 30 Shift register SW switch DS Delay time shortening terminal 40 Overcharge detection circuit 50 Overdischarge detection circuit 60 Discharge overcurrent detection circuit 70 Charge overcurrent detection circuit 80, 120 Logic circuit 90 Level shift circuit 100 Short circuit detection circuit 110 Delay circuit 150, 150a, 150b, 250 Integrated circuit device for secondary battery protection 200 Clock pulse supply means during inspection 300 Constant voltage power supply COUT Charge detection terminal DOUT Discharge detection terminal V- Current detection terminal

Claims (4)

An internal oscillator that generates clock pulses during operation;
A delay time generating means for generating a delay time of each internal circuit based on the input clock pulse;
A delay time shortening pin that can input clock pulses from the outside during inspection;
During normal operation, the internal oscillator and the delay time generating means are connected so that the delay time is generated based on the clock pulse during operation, and when testing electrical performance, the delay time shortening terminal and the delay time generating unit A connection switching means for connecting the delay time generating means so that the delay time is generated based on the clock pulse at the time of inspection;
A shift register connected to the delay time shortening terminal,
The shift register counts the inspection clock pulse input to the delay time shortening terminal,
The connection switching means connects the delay time shortening terminal and the delay time generating means when the number of the inspection clock pulses counted by the shift register is equal to or greater than a predetermined number . Integrated circuit device.   2. The integrated circuit device for protecting a secondary battery according to claim 1, wherein a clock pulse having a frequency higher than that of the clock pulse for operation is input as the clock pulse for inspection, and the delay time is shortened. The internal oscillator is connected to the delay time shortening terminal, and when a constant voltage is input instead of the clock pulse at the time of inspection, the delay time is shortened using the shortened clock pulse generated by the internal oscillator. The integrated circuit device for protecting a secondary battery according to claim 1 , wherein: A method for testing an integrated circuit device for secondary battery protection according to any one of claims 1 to 3 ,
The inspection clock pulse having a frequency higher than the operation clock pulse generated by the internal oscillation circuit of the secondary battery protection integrated circuit device is input to the delay time shortening terminal of the secondary battery protection integrated circuit device, An inspection method for an integrated circuit device for protecting a secondary battery, wherein the electrical characteristics are inspected in a state in which a delay time of an internal circuit of the integrated circuit device for protecting a secondary battery is shortened.

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