ELECTRONIC CIRCUIT ARRANGEMENT FOR MONITORING TEMPERATURES

Abstract

An electronic circuit arrangement for monitoring temperatures includes an electronic temperature-determining circuit with a temperature sensor for measuring an ambient temperature in the surroundings of the temperature sensor, configured to generate a comparator input signal depending on the temperature measured by the temperature sensor, an electronic reference circuit including a secondary temperature sensor for measuring an ambient temperature of the electronic circuit arrangement which is configured to generate a secondary comparator input signal that is dependent on the temperature measured by the secondary temperature sensor, an electronic comparator circuit which compares the primary and the secondary comparator input signal and generates a comparator output signal dependent on the two input signals. The temperature-determining circuit, the reference circuit and the comparator circuit are configured such that the comparator circuit generates a trigger signal as the comparator output signal if the temperature measured by the temperature sensor exceeds a temperature reference value.

Claims

1. An electronic circuit arrangement for monitoring temperatures, the electronic circuit arrangement comprising: at least one electronic temperature-determining circuit, which comprises a primary temperature sensor for measuring a temperature in the immediate surroundings of the primary temperature sensor and which is designed/configured to generate a primary comparator input signal that is dependent on the temperature measured by the primary temperature sensor; an electronic reference circuit which comprises at least one secondary temperature sensor for measuring an ambient temperature of the electronic circuit arrangement and which is designed/configured to generate a secondary comparator input signal that is dependent on the ambient temperature measured by the secondary temperature sensor; and an electronic comparator circuit which compares the primary and the secondary comparator input signal and generates a comparator output signal dependent on the two input signals, wherein the temperature-determining circuit, the reference circuit and the comparator circuit are configured in such a manner and matched to one another such that the comparator circuit generates an error or trigger signal as the comparator output signal if the temperature measured by the at least one primary temperature sensor exceeds a temperature reference value that is defined with the electronic reference circuit and that is dependent on the ambient temperature measured by the secondary temperature sensor.

2. The electronic circuit arrangement according to claim 1, further comprising an electrical feedback which brings about an adjustment of the temperature reference value, typically downwards when the error or trigger signal is generated by the comparator circuit.

3. The electronic circuit arrangement according to claim 1, wherein the electronic circuit arrangement is configured such that after the error or trigger signal is generated for the first time, the temperature monitoring is repeated iteratively until the measured temperature has again fallen below the temperature reference value adjusted with the electrical feedback.

4. The electronic circuit arrangement according to claim 1, wherein: two or more temperature-determining circuits for measuring an ambient temperature in the immediate surroundings of the respective primary temperature sensor are provided, and the at least two temperature-determining circuits, are configured, typically by using semiconductor diodes such that that primary temperature sensor with the higher or highest measured temperature is used to generate the primary comparator input signal.

5. The electronic circuit arrangement according to claim 1, wherein the electronic circuit arrangement comprises an extension connection with which the at least one temperature-determining circuit or the electronic circuit arrangement can be supplemented by at least one external temperature-determining circuit.

6. The electronic circuit arrangement according to claim 1, wherein the comparator circuit comprises a comparator element with a first and with a second comparator input and with a comparator output, and wherein the first comparator input is connected electrically to a signal output of the temperature-determining circuit and the second comparator input is connected electrically to a signal output of the electronic reference circuit.

7. The electronic circuit arrangement according to claim 1, wherein the electronic circuit arrangement is configured such that the temperature-determining circuit, the reference circuit and the comparator circuit can be connected to a common electrical voltage source for the electrical power supply.

8. The electronic circuit arrangement according to claim 1, wherein: the primary temperature sensor of the at least one temperature-determining circuit, and the secondary temperature sensor of the reference circuit each comprise an electronic component with a temperature-dependent electrical resistance, and the electronic component is typically an electrical NTC resistance or a PTC resistance.

9. A battery cell arrangement, comprising: at least one battery cell; an electrical supply connection which for connection of an electrical/electronic assembly of an electrical/electronic device to at least one battery cell is connected electrically to this with at least one electrical supply line; a semiconductor switch arranged in the electrical supply line which can be switched between an open state in which the electrical connection between the electrical supply connection and the at least one battery cell is interrupted and a closed state in which this interruption is cancelled; and at least one electronic circuit arrangement adapted/programmed for monitoring the temperature of the at least one battery cell and for switching the semiconductor switch between the open and the closed state.

10. The battery cell arrangement according to claim 9, wherein the electronic circuit arrangement is supplied with energy from the at least one battery cell.

11. The battery cell arrangement according to claim 9, wherein the electronic circuit arrangement and the at least one battery cell are matched to one another in such a manner that the circuit arrangement is supplied with electrical energy from the at least one battery cell even when the semiconductor switch is open.

12. An electrical or electronic device, comprising: a battery cell arrangement according to claim 9; and at least one electrical or/and electronic assembly which can be connected or is connected electrically to the at least one battery cell of the battery cell arrangement so that when the semiconductor switch is closed, the electrical/electronic assembly can be supplied with electrical energy from the battery cell arrangement.

13. The electrical or electronic device according to claim 12, wherein the electronic circuit arrangement is extended by an external temperature-determining circuit which is part of the at least one assembly and with which the temperature of the electrical/electronic device, in particular of the at least one electrical/electronic assembly can be monitored or is monitored.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The disclosure will now be described with reference to the drawings wherein:

[0031] FIG. 1 shows a circuit arrangement in a circuit-diagram like diagram according to an exemplary embodiment of the disclosure, and

[0032] FIG. 2 shows a battery cell arrangement with an electronic circuit arrangement shown in FIG. 1 according to an exemplary embodiment of the disclosure.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0033] FIG. 1 illustrates in a circuit-diagram-like diagram of an electronic circuit arrangement 1 according to an exemplary embodiment the disclosure. The circuit arrangement 1 accordingly comprises a first and a second electronic temperature-determining circuit 2a, 2b, an electronic reference circuit 3 and an electronic comparator circuit 4.

[0034] The operating mode of the first temperature-determining circuit 2a is explained hereinafter. The temperature-determining circuit 2a comprises a primary temperature sensor 5 for measuring an ambient temperature TU in the immediate surroundings of the primary temperature sensor 5. The temperature-determining circuit 2a is designed or configured for generating a primary comparator input signal which is supplied to the comparator circuit 4 for further processing. The primary comparator input signal depends on the temperature TU measured by the primary temperature sensor 5.

[0035] As can be seen in FIG. 1, the primary temperature sensor 5 of the temperature-determining circuit 2a comprises an electronic component 22 whose electrical resistance varies in a temperature-dependent manner. Expediently such an electronic component 22 can be an electrical NTC resistance 23. Alternatively to this, however, the use of a PTC resistance is also feasible. The NTC resistance 23 together with an Ohmic resistance 24 connected electrically in series forms an electrical voltage divider 25 which is arranged electrically between the supply line 21 and an electrical earth potential 26. A branch-off point 27 arranged between the primary temperature sensor 5 or the component 22 or the NTC resistance 23 and the Ohmic resistance 24 is connected electrically via an electrical conducting path 20c to a signal output 12 of the temperature-determining circuit 2a. If the electrical resistance of the primary temperature sensor 5 varies in a temperature-dependent manner, the value of the electrical voltage present at the branch-off point 27 varies accordingly. With increasing measured temperature TU, the electrical voltage present at the branch-off point 27 decreases when using an NTC resistance 23.

[0036] The second temperature-determining circuit 2b is constructed identically to the first temperature-determining circuit 2a. Preceding explanations to the first temperature-determining circuit 2a therefore apply mutatis mutandis also to the second temperature-determining circuit 2b.

[0037] The two temperature-determining circuits 2a, 2b are configured in such a manner and matched to one another so that that primary temperature sensor 5 with the highest measured temperature TU is used to generate the primary comparator input signal. For this purpose, according to FIG. 1 in both temperature-determining circuits 2a, 2b a semiconductor diode 28, typically in the form of a Schottky diode 29, is arranged between the branch-off point 27 and the signal output 12. If different temperature values are measured by the primary temperature sensors 5 of the two temperature-determining circuits 2a, 2b so that different electrical voltage values are present at the two branch-off points 27, the two semiconductor diodes 28 or Schottky diodes 29 have the effect that the lower of the two voltage values is provided at the signal output 12. Thus, at the signal output 12 of the two temperature-determining circuits 2a, 2b the signal of that one of the two primary temperature sensors 5 which has measured the higher temperature TU is provided.

[0038] The electronic reference circuit 3 is explained in detail hereinafter. In a similar manner to the temperature-determining circuits 2a, 2b, the electronic reference circuit 3 comprises a secondary temperature sensor 6 for measuring an ambient temperature TS of the electronic circuit arrangement 1. The reference circuit 3 is, in a similar manner to the temperature-determining circuit 2a or 2b, designed/configured to generate a secondary comparator input signal which is provided to the comparator circuit 4 for further processing.

[0039] As can be further seen in FIG. 1, the temperature reference value TS in the reference circuit 3 is defined with a voltage divider 35 which is formed by two Ohmic resistances 34a, 34b connected electrically in series. The voltage divider 35 is arranged electrically between the supply line 21 and an electrical earth potential 36. A branch-off point 37 arranged between the two Ohmic resistances 34a, 34b is connected electrically via an electrical conducting path 20d between the signal output 13 of the electronic reference circuit 3. The electrical voltage present at the branch-off point 37 is defined by the ratio of the resistance values of the two Ohmic resistances 34a, 34b.

[0040] According to FIG. 1, a semiconductor diode 38, typically in the form of a Schottky diode 39, is arranged in the reference circuit 3 between the branch-off point 37 and a signal output 13 of the reference circuit 3, in similar manner to the two temperature-determining circuits 2a, 2b. This semiconductor diode 38 or Schottky diode 39 produces an additional electrical voltage drop which compensates for the electrical voltage drop at the two semiconductor diodes 28 or Schottky diodes 29.

[0041] In addition to the two Ohmic resistances 34a, 34b, the secondary temperature sensor 6 is arranged electrically in series with these. The secondary temperature sensor 6, similarly to the first temperature sensor 5, can also be an electronic component 32 whose electrical resistance depends on the temperature and thus varies in a temperature-dependent manner. Expediently, the electronic component 32 can be an electrical NTC resistance 33. Alternatively to this however, the use of a PTC resistance is also feasible. The secondary temperature sensor 6 serves to take into account the general ambient temperature TS of the circuit arrangement 1 when monitoring temperatures. The NTC resistance 33 together with the Ohmic resistances 34a, 34b connected electrically in series forms an electrical voltage divider 35 which is arranged electrically between the supply line 21 and an electrical earth potential 36. If the electrical resistance of the secondary temperature sensor 6 varies in a temperature-dependent manner, the value of the electrical voltage present at the branch-off point 37 varies accordingly. With increasing measured temperature, the electrical voltage present at the branch-off point 37, when using an NTC resistance 33, decreases.

[0042] The electronic comparator circuit 4 is explained hereinafter. The electronic comparator circuit 4 compares the primary comparator input signal generated by the temperature-determining circuits 2a, 2b and provided at the signal output 12 with the secondary comparator input signal generated by the reference circuit 3 and provided at the signal output 13 and generates a comparator output signal depending on the two input signals.

[0043] In this case, the comparator circuit 4 generates as the comparator output signal an error or trigger signal when the temperature T.sub.U measured by at least one of the two primary temperature sensors 5 exceeds the temperature reference value T.sub.Ref defined with the reference circuit 3. Thus, if the temperature reference value T.sub.Ref is suitably defined, it can be identified that there is the risk of an overheating of the components being temperature-monitored with the primary temperature sensors 5, for example of one or more battery cells. The temperature monitoring of one or several electrical/electronic assemblies is also feasible in a similar manner. In this way, suitable counter-measures can optionally be initiated. Such a counter-measure can possibly be a more intensive temperature monitoring until this falls below the temperature reference value T.sub.Ref again. The electronic circuit arrangement 1 can be configured for this purpose so that after an error or trigger signal has been generated for the first time, the temperature monitoring is repeated iteratively until the temperature T.sub.U measured by the temperature-determining circuits 2a, 2b falls below the temperature reference value T.sub.Ref again. Alternatively or additionally as a countermeasure it is also possible to shut off the relevant component, i.e., in particular it is feasible to separate the component from the power or voltage supply. The same applies to the electrical/electronic assemblies.

[0044] According to FIG. 1, the comparator circuit 4 comprises a comparator element 8 which can be formed by an operational amplifier 9. The comparator element 8 or the operational amplifier 9 comprises a first and a second comparator input 10a, 10b as well as a comparator output 11. The comparator output signal generated by the comparator element 8 or operational amplifier 9, generated at the comparator output 11 depends on a comparison of the first comparator input signal present at the first comparator input 10a with the second comparator input signal present at the second comparator input 10b.

[0045] According to FIG. 1, the first comparator input 10a is connected electrically via an electrical connecting path 20a to the signal output 12 of the temperature-determining circuits 2a, 2b. Accordingly, the second comparator input 10b is connected electrically via an electrical conducting path 20b to the signal output 13 of the electronic reference circuit 3. In this way, the electrical voltage values provided at the signal output 12 of the temperature-determining circuits 2a, 2b or provided at the signal output 13 of the reference circuit 3 are provided to the two comparator inputs 10a, 10b.

[0046] As can be seen in FIG. 1, the electronic circuit arrangement 1 can have an electrical feedback 7 between the comparator circuit 4 and the reference circuit 3, indicated highly schematically in FIG. 1. This feedback 7 is designed so that when the error or trigger signal is generated by the comparator circuit 4, it brings about an adjustment of the temperature reference value T.sub.Ref, typically downwards. For this purpose, an electrical conducting path 20f can be provided which electrically connects the comparator output 11 to the branch-off point 37 of the electronic reference circuit 3. An additional Ohmic resistance 34c can be arranged in the conducting path 20f, in similar manner to the two Ohmic resistances 34a, 34b. In this way, if the three Ohmic resistances 34a, 34b, 34c are suitably dimensioned, the electrical voltage present at the branch-off point 37 is increased, with the result that this is accompanied by the desired adjustment of the temperature reference value T.sub.Ref downwards.

[0047] As the circuit-diagram-like diagram in FIG. 1 illustrates, the electronic circuit arrangement 1 is configured in such a manner that the temperature-determining circuits 2a, 2b, the reference circuit 3 and the comparator circuit can be connected to a common electrical voltage source 15 for the purpose of the electrical voltage supply. For this purpose, a common electrical supply line 21 is provided with a supply connection 16 to which said voltage source 15 can be connected. With the common electrical supply line 21, in particular the comparator element 8 as an active electronic component can be supplied with electrical energy from the electrical voltage source 15.

[0048] According to FIG. 1, the electronic circuit arrangement 1 can also have an electrical extension connection 14 with which the temperature-determining circuits 2a, 2b of the electronic circuit arrangement 1 can be supplemented by at least one external temperature-determining circuit (not shown in FIG. 1).

[0049] FIG. 2 illustrates an application example for the electronic circuit arrangement 1 of FIG. 1. FIG. 2 shows an electrical or electronic device 60 in schematic view. The device 60 can, for example, be a mobile telephone. Accordingly, the device 60 comprises a battery cell arrangement 50 with a battery cell 51. Naturally the arrangement 50 can also comprise two or more battery cells 51 (not shown). The battery cell arrangement 50 comprises an electrical supply connection 53 which is connected electrically to the battery cell 51 with an electrical supply line 54. One or more electrical/electronic assemblies 52 with electrical/electronic components 58 of the device 60 can be connected at the electrical supply connection 53 so that these can obtain electrical energy from the battery cell 51. The battery cell arrangement 50 and the at least one electrical/electronic assembly 52 can be arranged in separate housings.

[0050] As can be seen from FIG. 2, a semiconductor switch 55 is arranged in the electrical supply line 54. The semiconductor switch 55 can be formed by a field effect (FET) transistor 56 which has a source connection 57a, a drain connection 57b and a gate connection 57c. The semiconductor switch 55 can be switched between an open state in which the electrical connection between the electrical supply connection 53 and the battery cell 51 is interrupted and a closed state in which this interruption is cancelled so that an electrical current can flow through the supply line 54. The switchover between the open and closed state is accomplished by triggering the gate connection 57c with the aid of the electronic circuit arrangement 1 which is also a part of the battery cell arrangement 50. For this purpose, the comparator output 11 of the comparator circuit 4 is connected electrically via an electrical conducting path 20d to the gate connection 57c of the semiconductor switch 55 or the FET 56.

[0051] The semiconductor switch 55 or the FET 56 and the electronic circuit arrangement 1 are matched to one another in such a manner that the semiconductor switch 55 or FET 56 is switched into the open state when the comparator circuit generates as the comparator output signal the error or trigger signal already explained in connection with FIG. 1 when the temperature reference value T.sub.Ref is exceeded.

[0052] As FIG. 2 illustrates, the comparator circuit 4, in particular the comparator element 8 or operational amplifier 9 is connected via an electrical conducting path 20e, which is electrically connected to the supply line 54, can be supplied with electrical energy from the battery cell 51. Expediently the electronic circuit arrangement and the at least one battery cell are matched to one another such that the circuit arrangement 1 is supplied with electrical energy from the battery cell 51 even when the semiconductor switch 55 or FET 56 is open. During operation the temperature-determining circuit 2a of the circuit arrangement 1 monitors the temperature of the battery cell 51. The operating mode of the circuit arrangement 1 has already been explained by reference to FIG. 1. The temperature-determining circuit 2a and the reference circuit 3 are shown in highly simplified form in FIG. 2 compared with the diagram in FIG. 1 for reasons of clarity.

[0053] In the example in FIG. 2 the electronic circuit arrangement 1 comprises the electrical extension connection 14 already explained in connection with FIG. 1 to which an external temperature-determining circuit 2c can be connected, which is constructed identically to the temperature-determining circuit 2a and thus follows the same functional principle. In contrast to the temperature-determining circuit 2a, however, the temperature-determining circuit 2c is not part of the electronic circuit arrangement 1 of the battery cell arrangement 50 but part of the electronic/electrical assembly 52 of the device 60. The external temperature-determining circuit 2c takes over the function of the second temperature-determining circuit 2b of FIG. 1 and monitors the temperature of the electrical/electronic components 58 of the electrical/electronic assembly 52.

[0054] It is understood that the foregoing description is that of the exemplary embodiments of the disclosure and that various changes and modifications may be made thereto without departing from the spirit and scope of the disclosure as defined in the appended claims.