CN219641811U - Weak current test circuit - Google Patents
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- CN219641811U CN219641811U CN202321166436.9U CN202321166436U CN219641811U CN 219641811 U CN219641811 U CN 219641811U CN 202321166436 U CN202321166436 U CN 202321166436U CN 219641811 U CN219641811 U CN 219641811U
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- 238000012360 testing method Methods 0.000 title claims abstract description 61
- 239000003990 capacitor Substances 0.000 claims description 128
- 235000014676 Phragmites communis Nutrition 0.000 claims description 21
- 230000010354 integration Effects 0.000 abstract description 20
- 238000010586 diagram Methods 0.000 description 5
- 239000003985 ceramic capacitor Substances 0.000 description 4
- 238000001914 filtration Methods 0.000 description 4
- 229910052715 tantalum Inorganic materials 0.000 description 4
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 4
- 238000005259 measurement Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 239000004793 Polystyrene Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
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Abstract
The utility model provides a weak current test circuit, comprising: the device comprises an operational amplifier, a potentiometer and an integrating device, wherein the integrating device is arranged in parallel with the operational amplifier, the input end of the potentiometer is connected with a first offset zero setting end of the operational amplifier, the output end of the potentiometer is connected with a second offset zero setting end of the operational amplifier, and the pointer end of the potentiometer is connected with a negative power supply end of the operational amplifier. Before weak current is tested, the input offset voltage of the operational amplifier is zeroed by utilizing a potentiometer, the influence of the input offset voltage on the weak current test result is eliminated, then the integration device is utilized for integration, the output voltage of the integration stage is measured at the output end of the operational amplifier, and the weak current test result is obtained according to the measured output voltage. Because the integration device is used for integrating to test the weak current under the condition that the influence of the input offset voltage is eliminated, the accuracy and the reliability of the weak current test result can be ensured.
Description
Technical Field
The utility model relates to the technical field of current signal measurement, in particular to a weak current test circuit.
Background
As the accuracy requirements of the chip electrical parameters of semiconductors are higher and higher, the requirements of chip current parameter detection range from μa (microampere), nA (nanoamp) to pA (picoamp) and even to fA (femtoaamp) levels, and more accurate test circuits are needed to meet the requirements.
At present, for weak current test, a current signal is often converted into a voltage signal by using a resistor with an oversized resistance, but thermal noise exists in the resistor, noise voltage is generated, the larger the resistance value is, the larger the noise voltage is, and the resistance value of the resistor is changed due to heating when current passes through the resistor with the larger resistance value, so that the weak current test result is affected, and the measurement inaccuracy is caused.
Disclosure of Invention
Accordingly, the present utility model is directed to a weak current testing circuit for solving or partially solving the above-mentioned problems.
Based on the above object, the present utility model provides a weak current test circuit, comprising:
the integrated device is arranged in parallel with the operational amplifier, the input end of the potentiometer is connected with the first offset zero setting end of the operational amplifier, the output end of the potentiometer is connected with the second offset zero setting end of the operational amplifier, and the pointer end of the potentiometer is connected with the negative power supply end of the operational amplifier.
Further, one end of the integrating device is connected with the inverting input end of the operational amplifier and the first reed relay respectively, and the other end of the integrating device is connected with the output end of the operational amplifier and the first resistor respectively.
Further, the integrating device includes: a first capacitor and a second resistor, the first capacitor and the second resistor being arranged in parallel;
one end of the first capacitor is respectively connected with the inverting input end of the operational amplifier and the first reed relay, and the other end of the first capacitor is respectively connected with the output end of the operational amplifier and the first resistor;
one end of the second resistor is connected with the input end of the second reed relay, and the other end of the second resistor is respectively connected with the inverting input end of the operational amplifier and the first reed relay.
Further, a power supply end of the operational amplifier is connected with the power supply unit.
Further, the power supply unit includes: a first power supply unit and a second power supply unit;
the output end of the first power supply unit is connected with the negative power supply end of the operational amplifier and one end of the second capacitor respectively, and the output end of the second power supply unit is connected with the positive power supply end of the operational amplifier and one end of the third capacitor respectively.
Further, the other end of the second capacitor is grounded, and the other end of the third capacitor is grounded.
Further, the first power supply unit includes: the first bypass capacitor device is arranged in parallel with the second bypass capacitor device;
the input end of the first voltage regulator is respectively connected with the first bypass capacitor device and the negative power supply end in a power supply mode, the output end of the first voltage regulator is connected with the second bypass capacitor device, and the grounding end of the first voltage regulator is grounded.
Further, the first bypass capacitor device includes: a fourth capacitor and a fifth capacitor, the second bypass capacitance device comprising: a sixth capacitor and a seventh capacitor.
Further, the second power supply unit includes: the second voltage regulator, the third bypass capacitor device and the fourth bypass capacitor device are arranged in parallel;
the input end of the second voltage regulator is respectively connected with the third bypass capacitor device and the positive power supply end in a power supply mode, the output end of the second voltage regulator is connected with the fourth bypass capacitor device, and the grounding end of the second voltage regulator is grounded.
Further, the third bypass capacitor device includes: an eighth capacitor and a ninth capacitor, the fourth bypass capacitance device comprising: a tenth capacitor and an eleventh capacitor.
As can be seen from the above, in the weak current test circuit provided by the utility model, before the weak current is tested, the input offset voltage of the operational amplifier is zeroed by using the potentiometer, the influence of the input offset voltage on the weak current test result is eliminated, after the input offset voltage is zeroed, the weak current test result is obtained by integrating the weak current test circuit by using the integrating device, the output voltage of the integrating stage is measured at the output end of the operational amplifier, and the weak current test result is obtained according to the measured output voltage. Because the integration device is used for integrating to test the weak current under the condition that the influence of the input offset voltage is eliminated, the accuracy and the reliability of the weak current test result can be ensured.
Drawings
In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a weak current test circuit according to an embodiment of the utility model;
FIG. 2 is a first schematic diagram of a weak current testing circuit according to another embodiment of the present utility model;
FIG. 3 is a second schematic diagram of a weak current testing circuit according to another embodiment of the present utility model;
FIG. 4A is a third schematic diagram of a weak current testing circuit according to another embodiment of the present utility model;
fig. 4B is a fourth schematic diagram of a weak current testing circuit according to still another embodiment of the present utility model.
Detailed Description
The present utility model will be further described in detail below with reference to specific embodiments and with reference to the accompanying drawings, in order to make the objects, technical solutions and advantages of the present utility model more apparent.
It should be noted that unless otherwise defined, technical or scientific terms used in the embodiments of the present utility model should be given the ordinary meaning as understood by one of ordinary skill in the art to which the present disclosure pertains. The terms "first," "second," and the like, as used in this disclosure, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.
As shown in fig. 1, a weak current test circuit according to this embodiment includes:
the operational amplifier 110, the potentiometer 120 and the integrating device 130, the integrating device 130 is arranged in parallel with the operational amplifier 110, the input end of the potentiometer 120 is connected with the first offset zero setting end of the operational amplifier 110, the output end of the potentiometer 120 is connected with the second offset zero setting end of the operational amplifier 110, and the pointer end of the potentiometer 120 is connected with the negative power supply end of the operational amplifier 110.
In the above scheme, since the operational amplifier 110 has the input offset voltage and the input bias current, which may affect the weak current test result, the operational amplifier 110 selects the precision operational amplifier device AD549, the maximum input bias current of which is 60fA, typically only 20fA, which is far smaller than the test target current, so that the influence of the bias current of the operational amplifier 110 is negligible for measuring the weak current of nA level or even pA level, and the influence of the input bias current on the weak current test result can be eliminated.
Because the model precision operational amplifier device AD549 selected by the operational amplifier 110 can maximally reach 300uV in input offset voltage, the measurement precision can be influenced when weak currents of pA level and nA level are measured, before weak currents are tested, the input offset voltage of the operational amplifier 110 is zeroed by the potentiometer 120, the pointer end of the potentiometer 120 is controlled to slide by slowly rotating the knob of the potentiometer 120, then the voltage value of the inverting input end of the operational amplifier is measured by the high-precision universal meter, and the voltage value of the inverting input end of the operational amplifier is as close to 0V as possible, so that the zeroing of the input offset voltage of the operational amplifier 110 is realized, and the influence of the offset voltage on weak current test results is eliminated.
Then, the integration device 130 is used for integration, the output voltage of the integration stage is measured at the output end of the operational amplifier 110, and the weak current test result is obtained according to the measured output voltage. Because the integration device is used for integrating to test the weak current, the influence of the input offset voltage and the input bias current is eliminated, and therefore the accuracy and the reliability of the weak current test result can be ensured.
In a specific embodiment, as shown in fig. 2, one end of the integrating device 130 is connected to the inverting input terminal of the operational amplifier 110 and the first reed relay 140, and the other end of the integrating device 130 is connected to the output terminal of the operational amplifier 110 and the first resistor 150, respectively.
In the above scheme, the first reed relay 140 is controlled to be opened and closed to control the access of the weak current to be tested, and after the operational amplifier 110 is zeroed by the potentiometer 120, the first reed relay 140 is controlled to be closed to access the weak current to be tested, so that the influence of the offset voltage on the weak current test result is eliminated, and the accuracy and reliability of the weak current test result are improved.
In addition, with the first reed relay 140 belonging to the contact type, there is almost no leakage phenomenon at the time of disconnection, further improving the accuracy and reliability of the weak current test result.
The other end of the integrating device 130 is connected with a first resistor 150 with smaller resistance, the total resistance of the weak current test circuit at the output end is increased by using the first resistor 150, and the current passing through the circuit at the output end is reduced, so that the effect of protecting the weak current test circuit is realized.
In a specific embodiment, as shown in fig. 3, the integrating device 130 includes: a first capacitor 131 and a second resistor 132, the first capacitor 131 and the second resistor 132 being arranged in parallel;
one end of the first capacitor 131 is connected to the inverting input terminal of the operational amplifier 110 and the first reed relay 140, and the other end of the first capacitor 131 is connected to the output terminal of the operational amplifier 110 and the first resistor 150;
one end of the second resistor 132 is connected to an input end of the second reed relay 133, and the other end of the second resistor 132 is connected to an inverting input end of the operational amplifier 110 and the first reed relay 140, respectively.
In the above scheme, since the capacitor used for integration has a problem of leakage during integration and affects the weak current test result, the first capacitor 131 is a polystyrene capacitor, which has extremely low leakage current, and can minimize the error of the weak current test result due to capacitor leakage.
In addition, the operational amplifier 110 has the problem of integral drift, so that the weak current test result is affected, and therefore, the first capacitor 131 and the second resistor 132 are used for being connected in parallel, direct current negative feedback is introduced, and integral drift is effectively restrained, wherein the second resistor 132 is an EE series precise metal film resistor, the precision is high (one ten thousandth), the temperature coefficient is small, the stability is good, and the influence on the weak current test result caused by noise voltage generated by thermal noise due to the resistor can be avoided.
In addition, the second reed relay 133 is used, so that the leakage phenomenon hardly exists when the second reed relay is disconnected, and the accuracy and the reliability of the weak current test result are further improved.
The process of integrating the weak current by using the integrating device 130 is as follows:
the method is divided into three stages:
first, at time t1, the integration preparation phase (where op amp 110 has been zeroed via potentiometer 120, and thus the input offset voltage is zero): during the test, the input bias current of op amp 110 is negligible because of the fA level. The start and end of the circuit integration are controlled by manipulating the opening and closing of the second reed relay 133. When the second reed relay 133 is closed, since the insulation resistance of the first capacitor 131 is up to 100gΩ, the current almost flows through the second resistor 132, and the circuit forms a transimpedance circuit, and at this time, an output voltage vout_0 is measured at the output end of the operational amplifier 110, where vout_0= -Iin R, iin represents the weak current to be measured, R represents the resistance of the second resistor 132, and minus sign represents the direction of the weak current.
In the second stage, time t2 is an integration stage, when the second reed relay 133 is turned off, the integration of the first capacitor 131 is started, and the integration time period is t seconds, and at this time, the output voltage vout_1 is measured at the output end of the operational amplifier 110, where vout_1= -Iin t/CF-vout_0, where Iin represents the weak current of the target to be measured, C F Representing the capacitance of the first capacitor 131, t representing the duration of integration, vout_0 representing the output voltage measured at the output of the op amp 110 during the first phase, and minus-representing the direction of the weak current.
In the third stage, the second reed relay 133 is closed at the end of integration, and the output voltage value measured at the output terminal of the operational amplifier 110 is equal to that in the first stage.
The weak current of the target to be detected can be calculated through integration of the second stage:
Iin＝(-Vout 1 +Vout 0 )*C F /t
where Iin represents the weak current of the target to be measured, vout_0 represents the output voltage measured at the output terminal of the operational amplifier 110 in the first stage, vout_1 represents the output voltage measured at the output terminal of the operational amplifier 110 in the second stage, t represents the duration of integration, and the negative sign-represents the direction of the weak current.
In a specific embodiment, as shown in fig. 4A and 4B, the power supply terminal of the operational amplifier 110 is connected to the power supply unit 160.
In the above scheme, the operational amplifier 110 needs to provide a power supply for operation, and the power supply unit 160 is connected to the power supply terminal of the operational amplifier 110 to supply power to the operational amplifier 110.
In a specific embodiment, as shown in fig. 4A and 4B, the power supply unit 160 includes: a first power supply unit 161 and a second power supply unit 162;
the output terminal of the first power supply unit 161 is connected to the negative power supply terminal of the operational amplifier 110 and one terminal of the second capacitor 170, and the output terminal of the second power supply unit 162 is connected to the positive power supply terminal of the operational amplifier 110 and one terminal of the third capacitor 180.
In the above-mentioned scheme, the operational amplifier 110 needs to provide a power supply, so the first power supply unit 161 is connected to the negative power supply terminal of the operational amplifier 110, and the second power supply unit 162 is connected to the positive power supply terminal of the operational amplifier 110.
The second capacitor 170 is disposed beside the first power supply unit 161, and the third capacitor 180 is disposed beside the first power supply unit 162, and serves as a bypass capacitor to filter out high-frequency components in the circuit, so as to avoid affecting the weak current test precision, and further improve the accuracy of the weak current test result.
In a specific embodiment, as shown in fig. 4A, the other end of the second capacitor 170 is grounded, and the other end of the third capacitor 180 is grounded.
In the above scheme, the power supply needs to carry as little noise and noise as possible, and the other ends of the second capacitor 170 and the third capacitor 180 are grounded, so that the high-frequency noise in the circuit is bypassed to GND (Ground), thereby avoiding the influence of the noise interference on the accuracy of the weak current test result.
In a specific embodiment, as shown in fig. 4B, the first power supply unit 161 includes: a first voltage regulator 1611, a first bypass capacitor device 1612, and a second bypass capacitor device 1613, the first bypass capacitor device 1612 being arranged in parallel with the second bypass capacitor device 1613;
the input end of the first voltage regulator 1611 is respectively connected with the first bypass capacitor device 1612 and the negative power supply end, the output end of the first voltage regulator 1611 is connected with the second bypass capacitor device 1613, and the ground of the first voltage regulator 1611 is grounded.
In the above-mentioned scheme, the first power supply unit 161 supplies power to the negative power supply terminal of the operational amplifier 110, if there is a large amount of noise and clutter in the power supply, the accuracy of the weak current test result will be improved, so the power supply needs to carry as little noise and clutter as possible, and therefore the first voltage regulator 1611 is utilized in the first power supply unit 161, the first voltage regulator 1611 selects the voltage regulator LM7915, and the first bypass capacitor 1612 and the second bypass capacitor 1613 connected in parallel are provided to bypass the high-frequency noise in the first power supply unit 161 to GND (Ground), so as to avoid the noise from entering the operational amplifier 110 and affecting the accuracy of the weak current test result.
In a specific embodiment, as shown in fig. 4B, the first bypass capacitor device 1612 includes: a fourth capacitor 16121 and a fifth capacitor 16122, the second bypass capacitance device 1613 includes: a sixth capacitor 16131 and a seventh capacitor 16132.
In the above scheme, the first bypass capacitor device 1612 includes the fourth capacitor 16121 and the fifth capacitor 16122 connected in parallel, and the second bypass capacitor device 1613 includes the sixth capacitor 16131 and the seventh capacitor 16132 connected in parallel.
The negative terminal of the fourth capacitor 16121 is connected to the input terminal of the first voltage regulator 1611, and the negative terminal of the seventh capacitor 16131 is connected to the output terminal of the first voltage regulator 1611.
Among them, the fourth capacitor 16121 and the seventh capacitor 16131 are tantalum capacitors, which have much smaller volume, longer service life and higher temperature resistance. The fifth capacitor 16122 and the sixth capacitor 16132 are ceramic capacitors, and the working frequency range of the circuit such as the filtering oscillation bypass is large, so that the circuit can be used for a high-frequency circuit, and the tantalum capacitor and the ceramic capacitors are combined to play a role in filtering high-frequency noise through the bypass.
In a specific embodiment, as shown in fig. 4B, the second power supply unit 162 includes: a second voltage regulator 1621, a third bypass capacitor 1622, and a fourth bypass capacitor 1623, the third bypass capacitor 1622 and the fourth bypass capacitor 1623 being disposed in parallel;
the input end of the second voltage regulator 1621 is respectively connected with the third bypass capacitor 1622 and the positive power supply, the output end of the second voltage regulator 1621 is connected with the fourth bypass capacitor 1623, and the ground of the second voltage regulator 1621 is grounded.
In the above-mentioned scheme, the second power supply unit 162 supplies power to the positive power supply terminal of the operational amplifier 110, if there is a lot of noise and clutter in the power supply, the accuracy of the weak current test result will be improved, so the power supply needs to carry as little noise and clutter as possible, and therefore the second voltage regulator 1621 is utilized in the second power supply unit 162, the second voltage regulator 1621 selects the voltage regulator LM7815, and the third bypass capacitor 1622 and the fourth bypass capacitor 1623 connected in parallel are provided to bypass the high-frequency noise in the second power supply unit 162 to GND (Ground), so as to avoid the noise from entering the operational amplifier 110 and affecting the accuracy of the weak current test result.
In a specific embodiment, the third bypass capacitor device 1622 includes: an eighth capacitor 16221 and a ninth capacitor 16222, the fourth bypass capacitor 1623 including: a tenth capacitor 16231 and an eleventh capacitor 16232.
In the above scheme, the third bypass capacitor device 1622 includes the eighth capacitor 16221 and the ninth capacitor 16222 connected in parallel, and the fourth bypass capacitor device 1623 includes the tenth capacitor 16231 and the eleventh capacitor 16232 connected in parallel.
The positive terminal of the eighth capacitor 16221 is connected to the input terminal of the second voltage regulator 1621, and the positive terminal of the eleventh capacitor 16232 is connected to the output terminal of the second voltage regulator 1621.
Among them, eighth capacitor 16221 and eleventh capacitor 16232 are tantalum capacitors, which have much smaller volume, longer service life and higher temperature resistance. The ninth capacitor 16222 and the tenth capacitor 16231 are ceramic capacitors, and the working frequency range of the circuit such as the filtering oscillation bypass is large, and the circuit can be used for a high-frequency circuit, so that the tantalum capacitor and the ceramic capacitors are combined for use, and the effect of bypass filtering high-frequency noise can be better exerted.
Those of ordinary skill in the art will appreciate that: the discussion of any of the embodiments above is merely exemplary and is not intended to suggest that the scope of the utility model (including the claims) is limited to these examples; the technical features of the above embodiments or in the different embodiments may also be combined within the idea of the utility model, the steps may be implemented in any order and there are many other variations of the different aspects of the utility model as described above, which are not provided in detail for the sake of brevity.
The embodiments of the utility model are intended to embrace all such alternatives, modifications and variances which fall within the broad scope of the appended claims. Therefore, any omission, modification, equivalent replacement, improvement, etc. of the present utility model should be included in the scope of the present utility model.
Claims (10)
1. A weak current test circuit, comprising: the integrated device is arranged in parallel with the operational amplifier, the input end of the potentiometer is connected with the first offset zero setting end of the operational amplifier, the output end of the potentiometer is connected with the second offset zero setting end of the operational amplifier, and the pointer end of the potentiometer is connected with the negative power supply end of the operational amplifier.
2. The weak current test circuit according to claim 1, wherein one end of the integrating device is connected to the inverting input terminal of the operational amplifier and the first dry reed relay, respectively, and the other end of the integrating device is connected to the output terminal of the operational amplifier and the first resistor, respectively.
3. The weak current test circuit according to claim 2, wherein the integrating device comprises: a first capacitor and a second resistor, the first capacitor and the second resistor being arranged in parallel;
one end of the first capacitor is respectively connected with the inverting input end of the operational amplifier and the first reed relay, and the other end of the first capacitor is respectively connected with the output end of the operational amplifier and the first resistor;
one end of the second resistor is connected with the input end of the second reed relay, and the other end of the second resistor is respectively connected with the inverting input end of the operational amplifier and the first reed relay.
4. A weak current test circuit according to claim 1 or 3, wherein the power supply terminal of the operational amplifier is connected to a power supply unit.
5. The weak current test circuit of claim 4, wherein the power supply unit comprises: a first power supply unit and a second power supply unit;
the output end of the first power supply unit is connected with the negative power supply end of the operational amplifier and one end of the second capacitor respectively, and the output end of the second power supply unit is connected with the positive power supply end of the operational amplifier and one end of the third capacitor respectively.
6. The weak current test circuit of claim 5, wherein the other end of the second capacitor is grounded and the other end of the third capacitor is grounded.
7. The weak current test circuit of claim 5, wherein the first power supply unit comprises: the first bypass capacitor device is arranged in parallel with the second bypass capacitor device;
the input end of the first voltage regulator is respectively connected with the first bypass capacitor device and the negative power supply end in a power supply mode, the output end of the first voltage regulator is connected with the second bypass capacitor device, and the grounding end of the first voltage regulator is grounded.
8. The weak current test circuit of claim 7, wherein the first bypass capacitor device comprises: a fourth capacitor and a fifth capacitor, the second bypass capacitance device comprising: a sixth capacitor and a seventh capacitor.
9. The weak current test circuit according to claim 5 or 8, wherein the second power supply unit includes: the second voltage regulator, the third bypass capacitor device and the fourth bypass capacitor device are arranged in parallel;
the input end of the second voltage regulator is respectively connected with the third bypass capacitor device and the positive power supply end in a power supply mode, the output end of the second voltage regulator is connected with the fourth bypass capacitor device, and the grounding end of the second voltage regulator is grounded.
10. The weak current test circuit of claim 9, wherein the third bypass capacitor device comprises: an eighth capacitor and a ninth capacitor, the fourth bypass capacitance device comprising: a tenth capacitor and an eleventh capacitor.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321166436.9U CN219641811U (en) | 2023-05-15 | 2023-05-15 | Weak current test circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321166436.9U CN219641811U (en) | 2023-05-15 | 2023-05-15 | Weak current test circuit |
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| CN219641811U true CN219641811U (en) | 2023-09-05 |
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