CN103675428A - Power burr signal detection circuit and detection method thereof - Google Patents
Power burr signal detection circuit and detection method thereof Download PDFInfo
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Abstract
The invention discloses a power burr signal detecting circuit and a detection method thereof. The detection circuit comprises a power supply anode, a power supply cathode, a comparator, a first capacitor and a second capacitor. The first input port of the comparator is connected with the power supply anode through the first capacitor. The second input port of the comparator is connected with the power supply cathode through the second capacitor. According to the power burr signal detecting circuit and the detection method, the burr signal of a power supply is collected through the capacitors, direct current voltage can be isolated, and thus there is no direct current power consumption. Through isolating direct current voltage, the change of the direct current voltage of an attacked power supply has no influence on the circuit in the scheme, and the detection circuit has the advantages of flexible use and strong portability.
Description
Technical Field
The invention relates to the technical field of embedded systems, in particular to a power supply glitch signal detection circuit and a detection method.
Background
A power glitch (power glitch) attack is an attack means that some circuit units in a chip are affected by rapidly changing a power voltage or a ground voltage input to the chip, so that one or more circuit units enter an error state, thereby causing a chip processor to skip or implement an error operation according to the error state, and further gradually exposing security information hidden in the chip. At present, with the wide application of smart cards, information cards in the field of information security become key targets for hackers to attack.
In the prior art, a power glitch detection circuit generally comprises 4 links of glitch acquisition, operation, comparison and latching. The two links of comparison and latch are mainly realized by a comparator and a latch, and the acquisition and operation of the glitch are mainly realized by a resistor string. The purpose of detecting a glitch signal on a power supply is achieved by comparing the divided power supply voltage with a fixed reference voltage through a resistor string, and when the glitch occurs in the power supply voltage and the transient value of the glitch is higher or lower than the set reference voltage, an interruption alarm signal is generated by a comparator. In practical applications and chip designs, the voltage domain of the power glitch detection circuit and the attacked voltage domain are completely different. When the attacked voltage is collected through the resistor string, the problem that the actual signal input range of the following circuit needs to be considered inevitably at the time considering whether the following circuit can process the collected attacking signal or not.
Through the above research on the prior art and the consideration of the practical circuit application environment, it is easy to find that the prior art has the following disadvantages:
(1) there is direct current consumption when the resistor string gathers the mains voltage.
(2) The resistor string can only collect low-frequency signals on the power supply, and the high-frequency signals on the power supply cannot be collected in the same proportion.
(3) When the range of the detected power supply direct-current voltage is large and no burr attack exists, for example, under the condition of battery power supply, when the power supply voltage is slowly changed from 5.5v to 2.7v, the design difficulty of the later comparison link can be increased.
Disclosure of Invention
The invention provides a power supply burr signal detection circuit and a detection method, aiming at solving the technical problems that a power supply burr detection circuit in the prior art is large in power consumption and the detection circuit is influenced by the change of direct-current voltage of a detected power supply.
In one aspect of the present invention, a power glitch signal detection circuit includes: a power supply anode, a power supply cathode, a comparator, a first capacitor and a second capacitor,
a first input port of the comparator is connected with the positive pole of the power supply through a first capacitor, and a second input port of the comparator is connected with the negative pole of the power supply through a second capacitor.
The detection circuit further comprises a first reference voltage, a first resistor, a second reference voltage and a second resistor, wherein the first reference voltage is connected with a first input port of the comparator through the first resistor, and the second reference voltage is connected with a second input port of the comparator through the second resistor.
The detection circuit further comprises a third capacitor, and the first capacitor and the second capacitor are connected in series through the third capacitor.
The glitch signal voltage at the first input port is:
wherein,
is the glitch signal voltage at the first input port;
a power glitch signal voltage; c1 is the capacitance of the first capacitor, C3 is the capacitance of the third capacitorA capacitance value.
The detection circuit further comprises a shaper and a latch, and the comparator is connected with the latch through the shaper.
In another aspect of the present invention, a power glitch signal detection method is provided, including: the first capacitor and the second capacitor respectively collect burr signals of the positive electrode and the negative electrode of the power supply;
the comparator obtains the glitch signal voltage by comparing the voltage difference of the first input port and the second input port.
The method further comprises the following steps: the first reference voltage and the second reference voltage respectively provide direct current bias voltage for the comparator through the first resistor and the second resistor.
The method further comprises the following steps: the comparator further compares the burr signal voltage with an alarm threshold value and sends a comparison result to the shaper; the shaper converts the comparison result into a digital signal; the latch latches the digital signal, and when the comparison result shows that the voltage of the glitch signal is greater than the alarm threshold, the latch generates an interrupt alarm signal.
According to the power supply burr signal detection circuit and the detection method, the burr signal on the power supply is collected through the capacitor, and the direct-current voltage can be isolated, so that direct-current power consumption does not exist; in addition, the direct-current voltage is isolated, so that the circuit of the proposal cannot be influenced by the change of the direct-current voltage value of the attacked power supply, and the detection circuit is flexible to use and strong in transportability.
Drawings
FIG. 1 is a schematic diagram of a power glitch detection circuit according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a power glitch signal of the present invention being a negative-going glitch signal;
FIG. 3 is a schematic diagram of a power glitch signal of the present invention being a forward glitch signal;
fig. 4 is a schematic structural diagram of another embodiment of the power glitch detection circuit of the present invention.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings.
Example one
As shown in fig. 1, the embodiment of the power glitch signal detection circuit of the present invention includes: a power supply anode VCC, a power supply cathode VSS, a comparator COMP, a first capacitor C1 and a second capacitor C2,
input port a of COMP is connected to VCC through C1, and input port B of the comparator is connected to power supply negative VSS through C2.
The capacitors C1 and C2 form a sampling circuit for collecting the glitch signals of the anode and the cathode of the power supply. COMP obtains the glitch signal voltage by comparing the voltage difference between ports A, B.
When a glitch attack signal occurs on the supply voltage VCC, the capacitors C1 and C2 collect the glitch signal to the port A, B while isolating the dc signal of the supply voltage from the port A, B. The conversion of the VCC dc voltage does not have any effect on the following circuits.
In this embodiment, the detection circuit further includes a first reference voltage VREF1, a first resistor R1, a second reference voltage VREF2, and a second resistor R2. VREF1 is connected through R1 to input port a of COMP and VREF2 is connected through R2 to input port B of COMP.
The reference voltages VREF1 and VREF2 provide dc bias voltages for the comparator through resistors R1 and R2, respectively. Difference value Δ V of reference voltageREF＝|VREF1-VREF2L is the alarm threshold of the glitch signal, where VREF1Is the voltage value, V, of the reference voltage VREF1REF2Is the voltage value of the reference voltage VREF 2.
In practical applications, the power glitch attack signal may be a negative glitch attack signal, as shown in fig. 2, or a positive glitch attack signal, as shown in fig. 3. The detection can be realized by adjusting the values of VREF1 and VREF2 for different attack signal types without changing the main structure of the circuit.
The detection circuit in this embodiment further includes a shaper and a latch. The comparator is connected with the latch through the shaper.
The comparator further compares the glitch signal voltage with an alarm threshold and sends the comparison result to the shaper. The shaper converts the comparison result into a digital signal. The latch latches the digital signal, and when the comparison result shows that the voltage of the glitch signal is greater than the alarm threshold, the latch generates an interrupt alarm signal. Then, the processor can be used for carrying out real-time protection processing on each circuit unit according to the interrupt alarm signal so as to prevent information from being stolen.
Specifically, if VCC is used as the input signal and port a is used as the output terminal, the capacitor C1 and the resistor R1 constitute a high-pass filter circuit of the signal. With a time constant of T1＝R1*C1，R1Is the resistance value of the resistor R1, C1Is the capacitance value of the capacitor C1. Similarly, R2 and C2 form a high-pass filter circuit with a time constant of T2＝R2*C2，R2Is the resistance value of the resistor R2, C2Is the capacitance value of the capacitor C2. When the frequency of the alternating current signal on the positive pole VCC and the negative pole VSS of the power supply is higher than the bandwidth of the high-pass filter <math>
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</math> at this time, the ac voltage components at the positive and negative poles of the power supply are transmitted to A, B points, respectively. If the maximum frequency at which the comparator can compare the input signal is ftop, the frequency f of the VCC glitch signal that the detection circuit can detect when a glitch circuit appears on VCC isVCCIs in the range of f1≤fVCC≤ftop(ii) a Similarly, the detection circuit is capable of detecting the frequency f of the VSS glitch signal when the detection circuit is present at VSSVSSIs in the range of f2≤fVSS≤ftop。
In this embodiment, R1＝R2＝1MΩ，C1＝C21pf, at this time,the highest frequency of the AC input signal that can be detected by the comparator is 1GHz, and the frequency range of the glitch signal that can be detected by the circuit is
DC voltage of power supply VCCIs 5.5V and the voltage of VDD is 1.8V. By setting the voltage V of VREF1RELAnd voltage V of VREF2RE2FIn the range of 0.5 V.ltoreq.VREF1≤1.5V，0.5V≤VREF2Less than or equal to 1.5V to obtain-1V less than or equal to VREF1-VREF2Less than or equal to + 1V. Therefore, the amplitude range of the glitch signal voltage which can be detected by the detection circuit is-1V to + 1V.
The detection circuit in the embodiment collects the glitch signal on the power supply through the capacitor, and can isolate direct-current voltage, so that direct-current power consumption does not exist; in addition, the direct-current voltage is isolated, so that the circuit of the proposal cannot be influenced by the change of the direct-current voltage value of the attacked power supply, and the detection circuit is flexible to use and strong in transportability.
In addition, the purpose of detecting positive and negative voltage glitch signals can be realized by providing a reference voltage.
Example two
In the actual circuit implementation, the voltage of the glitch signal and the operating voltage of the detection circuit are issues that have to be considered. When the working voltage VDD of the detection circuit is much smaller than the voltage amplitude of the glitch signal, the detection circuit cannot normally detect the glitch signal.
In order to solve the above problem, as shown in fig. 4, the power glitch signal detection circuit of the present invention is configured to add a third capacitor C3 on the basis of the first embodiment. C1 and C2 are connected in series through C3. I.e. the glitch voltage at the power supply is divided by the capacitor C3 to reduce the glitch voltage at the input port a.
The glitch signal voltage at the port A of COMP is:
wherein,
is the glitch signal voltage at input port a;
is the glitch signal voltage at VCC; c1Is the capacitance value of the capacitor C1, C3Is the capacitance value of the capacitor C3.
If VCC is used as the input signal and point A is used as the output signal, then the capacitors C1, C3 and the resistor R1 constitute a high-pass filter circuit of the signal. With a time constant of T1＝R1*(C1+C3). Similarly, R2 and C2 form a high-pass filter circuit with a time constant of T2＝R2*C2. When the frequency of the alternating current signal on the positive pole VCC and the negative pole VSS of the power supply is higher than the bandwidth of the high-pass filter <math>
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</math> at times, the ac voltage components on the power supply and ground are delivered to A, B points, respectively. If the maximum frequency at which the comparator can compare the input signal is ftopWhen a glitch circuit is present on VCC, then the frequency f of the VCC glitch signal that the detection circuit is able to detectVCCIs in the range of f1≤fVCC≤ftop(ii) a Similarly, the detection circuit is capable of detecting the frequency f of the VSS glitch signal when the detection circuit is present at VSSVSSIs in the range of f2≤fVSS≤ftop。
In this design, R1＝R2＝1MΩ，C1＝C2＝C31pf, at this time,
the highest frequency of the AC input signal that can be detected by the comparator is 1GHz, and the frequency range of the VCC glitch signal that can be detected by the circuit is
The frequency range of the VSS glitch signal that can be detected is
The DC voltage of the power supply VCC is 5.5V and the voltage of VDD is 1.8V. By setting the voltage V of VREF1RE1FAnd voltage V of VREF2RE2FIn the range of 0.5 V.ltoreq.VREF1≤1.5V，0.5V≤VREF2Less than or equal to 1.5V to obtain-1V less than or equal to VREF1-VREF2Less than or equal to + 1V. Because the capacitor divides the voltage of the glitch signal, the amplitude range of the glitch signal voltage which can be detected by the detection circuit is-2V to + 2V.
Therefore, the capacitor voltage proportion is properly selected, so that the detected glitch voltage threshold (2V) is larger than the working voltage (1.8V) of the circuit. The design and application of the circuit are more flexible.
In this embodiment, through the size of the capacitance value of adjustment electric capacity C1 and C3, the voltage amplitude range of the burr signal that adjustment input port A that can be convenient goes out for detection circuit can normally detect the great burr signal of voltage amplitude.
The detection circuit can collect the burr signal of the high-frequency voltage and has the advantage of wide bandwidth range of the collected burr signal.
Based on the detection circuit, the invention also provides a power supply glitch signal detection method, which comprises the following steps: the first capacitor and the second capacitor respectively collect burr signals of the positive electrode and the negative electrode of the power supply; the comparator obtains the glitch signal voltage by comparing the voltage difference of the first input port and the second input port.
Preferably, the method further comprises: the first reference voltage and the second reference voltage respectively provide direct current bias voltage for the comparator through the first resistor and the second resistor.
More preferably, the method further comprises: the comparator further compares the burr signal voltage with an alarm threshold value and sends a comparison result to the shaper; the shaper converts the comparison result into a digital signal; the latch latches the digital signal, and when the comparison result shows that the voltage of the glitch signal is greater than the alarm threshold, the latch generates an interrupt alarm signal.
It should be noted that: the above embodiments are only used for illustrating the present invention and not for limiting, the present invention is not limited to the above examples, and all technical solutions and modifications thereof which do not depart from the spirit and scope of the present invention should be covered by the claims of the present invention.
Claims (8)
1. A power glitch signal detection circuit, comprising: a power supply anode, a power supply cathode, a comparator, a first capacitor and a second capacitor,
and a first input port of the comparator is connected with the anode of the power supply through a first capacitor, and a second input port of the comparator is connected with the cathode of the power supply through a second capacitor.
2. The detection circuit of claim 1, further comprising a first reference voltage, a first resistor, a second reference voltage, and a second resistor,
the first reference voltage is connected with a first input port of the comparator through a first resistor, and the second reference voltage is connected with a second input port of the comparator through a second resistor.
3. The detection circuit of claim 1, further comprising a third capacitance,
the first capacitor and the second capacitor are connected in series through the third capacitor.
4. The detection circuit of claim 3, wherein the glitch signal voltage at the first input port is:
5. The detection circuit of claims 1-4, further comprising a shaper and a latch,
the comparator is connected with the latch through the shaper.
6. A power supply burr signal detection method is characterized in that a first input port of a comparator is connected with a positive electrode of a power supply through a first capacitor, and a second input port of the comparator is connected with a negative electrode of the power supply through a second capacitor; the method comprises the following steps:
the first capacitor and the second capacitor respectively collect burr signals of the positive electrode and the negative electrode of the power supply;
the comparator obtains a glitch signal voltage by comparing a voltage difference between the first input port and the second input port.
7. The detection method according to claim 5, wherein a first reference voltage is connected to the first input port of the comparator through a first resistor, and a second reference voltage is connected to the second input port of the comparator through a second resistor; the method further comprises the following steps:
the first reference voltage and the second reference voltage respectively provide direct current bias voltage for the comparator through the first resistor and the second resistor.
8. The detection method according to claim 6 or 7, wherein the comparator is connected to the latch through the shaper, the method further comprising:
the comparator further compares the glitch signal voltage with an alarm threshold value and sends a comparison result to the shaper;
the shaper converts the comparison result into a digital signal;
and the latch latches the digital signal, and generates an interrupt alarm signal when the comparison result shows that the voltage of the glitch signal is greater than the alarm threshold.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104714193A (en) * | 2014-08-27 | 2015-06-17 | 北京中电华大电子设计有限责任公司 | High-precision low-power-consumption power glitch detection circuit |
| CN112132999A (en) * | 2019-06-25 | 2020-12-25 | 国民技术股份有限公司 | Safety testing method and system for intelligent access control equipment |
| TWI804449B (en) * | 2022-01-05 | 2023-06-01 | 聯發科技股份有限公司 | Chip with power-glitch detection |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101943729A (en) * | 2009-07-06 | 2011-01-12 | 北京中电华大电子设计有限责任公司 | Circuit for quickly detecting power sources and glitches on ground with low power consumption |
| CN101943728A (en) * | 2009-07-06 | 2011-01-12 | 北京中电华大电子设计有限责任公司 | Detection circuit capable of preventing attack of power supply burrs |
| US20130129116A1 (en) * | 2011-11-17 | 2013-05-23 | Infineon Technologies Ag | Glitch Detection and Method for Detecting a Glitch |
-
2013
- 2013-05-31 CN CN201310215260.6A patent/CN103675428A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101943729A (en) * | 2009-07-06 | 2011-01-12 | 北京中电华大电子设计有限责任公司 | Circuit for quickly detecting power sources and glitches on ground with low power consumption |
| CN101943728A (en) * | 2009-07-06 | 2011-01-12 | 北京中电华大电子设计有限责任公司 | Detection circuit capable of preventing attack of power supply burrs |
| US20130129116A1 (en) * | 2011-11-17 | 2013-05-23 | Infineon Technologies Ag | Glitch Detection and Method for Detecting a Glitch |
Non-Patent Citations (2)
| Title |
|---|
| 段晓毅: "《最新电压毛刺（Power Glitch）攻击与防御方法研究》", 《计算机科学》 * |
| 赵东艳: "《新型毛刺电压检测电路设计与实现》", 《信息安全与通信保密》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104714193A (en) * | 2014-08-27 | 2015-06-17 | 北京中电华大电子设计有限责任公司 | High-precision low-power-consumption power glitch detection circuit |
| CN112132999A (en) * | 2019-06-25 | 2020-12-25 | 国民技术股份有限公司 | Safety testing method and system for intelligent access control equipment |
| TWI804449B (en) * | 2022-01-05 | 2023-06-01 | 聯發科技股份有限公司 | Chip with power-glitch detection |
| US11916432B2 (en) | 2022-01-05 | 2024-02-27 | Mediatek Inc. | Chip with power-glitch detection |
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Application publication date: 20140326 |