B-type leakage protection circuit, integrated circuit chip thereof and b-type leakage protector

Abstract

The application discloses a B-type electric leakage protection circuit, an integrated circuit chip thereof and a B-type electric leakage protector. The electric leakage protection circuit comprises an electric leakage sampling module U1 provided with a magnetic ring coil; a current amplification circuit module U2 which outputs an oscillation current with adjustable duty ratio and whose duty ratio is modulated by the coil L1 and an electric leakage current difference induced by the coil; a temperature compensation module U4 which comprises a temperature compensation filter circuit, a temperature compensation generation circuit and a digital voltage source module DAC; a comparison circuit module U5 whose input ends are respectively connected to the output end of the current amplification circuit module U2 and the output end out of the digital voltage source module DAC, and which outputs a control voltage when the electric leakage current difference exceeds a predetermined value; and a driving circuit module P whose input end is connected to the output end of the comparison circuit module U5 and whose output end is connected to a tripper. The B-type electric leakage protector has the beneficial effects of high reliability, high precision, good consistency, low energy consumption, small size and low cost.

Description

Technical Field

[0001] This invention relates to a type B leakage current protection circuit, its integrated circuit chip, and a type B leakage current protector. Background Technology

[0002] Residual current devices (RCDs) are widely used in various electrical appliances, most commonly in household appliances. RCDs can be categorized into several types: AC type, designed for power frequency leakage current, reliably protecting against sudden, slowly rising, or instantaneously rising sinusoidal leakage currents; Type A, with a similar principle to AC type RCDs, reliably protecting against sinusoidal leakage signals as well as pulsating DC components; and Type B, which covers almost the entire range of low-voltage appliance leakage detection, including AC leakage signals, pulsating DC signals, smoothed DC signals, mixed signals, and high-frequency AC / DC signals, making it more widely applicable. Currently, most Type B RCDs on the market use analog chips, which suffer from high component dispersion, low accuracy, and lack of correctability. Summary of the Invention

[0003] To address the above shortcomings, this invention provides a Type B leakage current protection circuit that employs mixed analog-digital circuitry with automatic correction technology to achieve a 1% accuracy in judging leakage current below 5mA, with minimal variation among individual products manufactured.

[0004] The technical solution of this invention is:

[0005] A type B leakage current protection circuit includes:

[0006] The leakage current sampling module U1 is equipped with a magnetic ring coil. The magnetic ring CH in the magnetic ring coil can pass through the live wire L and the neutral wire N. The coil L1 in the magnetic ring coil can sense the leakage current difference between the live wire L and the neutral wire N, and output the leakage current difference to the next stage circuit.

[0007] The current amplifier circuit module U2 outputs an oscillating current with an adjustable duty cycle, and the duty cycle is modulated by the difference between the coil L1 and the leakage current it induced.

[0008] Temperature compensation module U4 includes: temperature compensation filter circuit, temperature compensation generator circuit and digital voltage source module DAC;

[0009] The temperature compensation filter circuit has its input terminal connected to the output terminal of the current amplifier circuit module U2, and its output terminal outputs the filtered voltage signal.

[0010] The temperature compensation generating circuit outputs a compensation voltage that is positively correlated with the ambient temperature.

[0011] The digital voltage source module DAC has its first input terminal in1 connected to the output terminal of the temperature compensation filter circuit, and its second input terminal in2 connected to the output terminal of the temperature compensation generator circuit. The digital voltage source module DAC is equipped with a voltage accumulation circuit, which can accumulate the voltages output by the temperature compensation filter circuit and the temperature compensation generator circuit and use them as the output terminal out of this stage circuit.

[0012] The input terminal of the comparator circuit module U5 is connected to the output terminal of the current amplifier circuit module U2 and the output terminal of the digital voltage source module DAC, respectively. When the leakage current difference exceeds a predetermined value, the control voltage is output.

[0013] The input terminal of the drive circuit module P is connected to the output terminal of the comparator circuit module U5. The output terminal of the drive circuit module P is connected to the trip unit. When the output terminal of the comparator circuit module U5 outputs a control voltage, the drive circuit module P can cause the trip unit to operate, ultimately disconnecting the live wire and / or neutral wire to supply power to the load.

[0014] The digital voltage source module (DAC) also includes a correction circuit, which is configured with:

[0015] The storage circuit provides a correction digital value based on the device parameters and experimental data, and stores the correction digital value in advance.

[0016] The digital-to-analog converter circuit has its input terminal connected to the output terminal of the storage circuit. The digital-to-analog converter circuit can convert the corrected digital value of the storage circuit into an analog voltage, and after voltage accumulation with the temperature compensation filter circuit and the temperature compensation generator circuit, it becomes the output terminal out of this stage circuit.

[0017] The aforementioned digital-to-analog converter circuit includes:

[0018] The first switch K1, the second switch K2, ... the Nth switch KN, one output terminal of the first switch K1, the second switch K2, ... the Nth switch KN is connected to the power supply E through resistors R81, R82 ... RN and R80 respectively. The other output terminal of the first switch K1, the second switch K2, ... the Nth switch KN is grounded. The control terminals of the first switch K1, the second switch K2, ... the Nth switch KN are respectively connected to the output terminals D0, D1 ... DN of the storage circuit.

[0019] The voltage accumulation circuit includes:

[0020] Amplifier IC4 has its positive input terminal connected to the common connection point of resistors R81, R82...RN and R80. The output terminal of amplifier IC4 is connected to the negative input terminal of amplifier IC4 in one way and to the output terminal out of the digital voltage source module DAC through resistor R91 in the other way.

[0021] Amplifier IC5 has its positive input terminal serving as the first input terminal in1 of the digital voltage source module DAC. One output terminal of amplifier IC5 is connected to the negative input terminal of amplifier IC5, and the other output terminal is connected to the output terminal out of the digital voltage source module DAC via resistor R92.

[0022] The positive input terminal of amplifier IC6 serves as the second input terminal in2 of the digital voltage source module DAC. One output terminal of amplifier IC6 is connected to the negative input terminal of amplifier IC6, and the other output terminal out of the digital voltage source module DAC is connected through resistor R93.

[0023] Preferably, the temperature compensation filter circuit includes:

[0024] Resistor R6 has one end connected to the output terminal of current amplifier circuit module U2 and the other end connected to ground via capacitor C2. The connection point of resistor R6 and capacitor C2 is connected to the first input terminal in1 of the digital voltage source module DAC. Resistor R6 and capacitor C2 form a low-pass filter.

[0025] The temperature compensation generating circuit includes:

[0026] The negative temperature coefficient thermistor RT has one path connected to the power supply E and the other path connected to ground via resistor R7. The connection point between the thermistor RT and resistor R7 is connected to the second input terminal in2 of the digital voltage source module DAC.

[0027] The current amplifier circuit module U2 includes:

[0028] In amplifier circuit IC1, one output terminal of coil L1 is connected to the negative input terminal of amplifier circuit IC1, and the other is connected to ground via resistor R1. The other output terminal of coil L1 is connected to the positive input terminal of IC1 via resistor R3. The positive input terminal of IC1 is also connected to ground via resistor R2. The output terminal of amplifier circuit IC1 serves as the output terminal of this stage circuit.

[0029] To better connect the preamplifier and amplifier circuits, the current amplifier circuit module U2 further includes:

[0030] Amplifier IC2 has two input terminals: one is grounded via filter capacitor C1, and the other is connected to the output terminal of amplifier IC1 via resistor R4; the other output terminal of amplifier IC2 is connected to the negative output terminal of amplifier IC2, and the other is also used as the output terminal of this current amplifier circuit module U2.

[0031] The comparison circuit module U5 includes: a comparison circuit IC3, the negative input terminal of the comparison circuit IC3 is connected to the output terminal of the amplifier circuit IC2, the positive input terminal of the comparison circuit IC3 is connected to the output terminal of the temperature compensation module U4, and the output terminal of the comparison circuit IC3 serves as the output terminal of the comparison circuit module U5.

[0032] The drive circuit module P has its input terminal connected to the output terminal of the comparator circuit module U5. The output terminal of the drive circuit module P can drive the trip unit to disconnect the live wire and the neutral wire to supply power to the load.

[0033] An integrated circuit chip for a type B leakage current protection circuit includes a current amplification circuit module U2, a temperature compensation module U4, and a comparator circuit module U5 as described in the type B leakage current protection circuit.

[0034] A type B residual current device includes the aforementioned type B residual current protection circuit, and also includes an integrated circuit chip for the aforementioned type B residual current protection circuit.

[0035] Compared with the prior art, the present invention has the following advantages:

[0036] By collecting and compensating for ambient temperature, the impact of ambient temperature on leakage protection circuits can be reduced. At the same time, the temperature performance requirements of components can be reduced, thus lowering costs.

[0037] By modifying the circuit and pre-inputting the modification parameters, the circuit can be adapted to components from different manufacturers and of different models, reducing procurement requirements and costs.

[0038] By employing a hybrid digital-analog converter with automatic correction technology, leakage current detection accuracy below 5mA can reach 1%, and the individual product differences are minimal, resulting in a significant improvement in product quality and a marked reduction in cost.

[0039] The Type B leakage current protector of this invention has the advantages of high reliability, high accuracy, good consistency, low energy consumption, small size and low cost. Attached Figure Description

[0040] Figure 1 This is the electrical schematic diagram of the present invention.

[0041] Figure 2 This is the electrical schematic diagram of the digital voltage source module (DAC) in this invention. Detailed Implementation

[0042] The present invention will now be further described with reference to the accompanying drawings:

[0043] like Figure 1 and Figure 2 As shown, a type B leakage current protection circuit includes:

[0044] The leakage current sampling module U1 is equipped with a magnetic ring coil. The magnetic ring CH in the magnetic ring coil can pass through the live wire L and the neutral wire N. The coil L1 in the magnetic ring coil can sense the leakage current difference between the live wire L and the neutral wire N and output the leakage current difference to the next stage circuit. If there is no leakage current, the coil L1 cannot sense the leakage current.

[0045] The current amplifier circuit module U2 outputs an oscillating current with an adjustable duty cycle, and the duty cycle is modulated by the difference between the coil L1 and the leakage current it induced.

[0046] Temperature compensation module U4 includes: temperature compensation filter circuit, temperature compensation generator circuit and digital voltage source module DAC;

[0047] The temperature compensation filter circuit has its input terminal connected to the output terminal of the current amplifier circuit module U2, and its output terminal outputs the filtered voltage signal.

[0048] The temperature compensation generating circuit outputs a compensation voltage that is positively correlated with the ambient temperature.

[0049] The digital voltage source module (DAC) has its first input terminal in1 connected to the output terminal of the temperature compensation filter circuit, and its second input terminal in2 connected to the output terminal of the temperature compensation generator circuit. The digital voltage source module (DAC) is equipped with a voltage accumulation circuit, which can accumulate the voltages output by the temperature compensation filter circuit and the temperature compensation generator circuit and use them as the output terminal out of this stage circuit.

[0050] The comparator circuit module U5 has its input terminals connected to the output terminals of the current amplifier circuit module U2 and the digital voltage source module DAC, respectively. When the leakage current difference exceeds a predetermined value, it outputs a control voltage.

[0051] The input terminal of the drive circuit module P is connected to the output terminal of the comparator circuit module U5. The output terminal of the drive circuit module P is connected to the trip unit. When the output terminal of the comparator circuit module U5 outputs a control voltage, the drive circuit module P can cause the trip unit to operate, ultimately disconnecting the live wire and / or neutral wire to supply power to the load.

[0052] It should be noted that introducing temperature compensation can correct the drift introduced by various components such as transformers, resistors, capacitors, and power supplies when temperatures change. This eliminates the need to rely on low-temperature drift devices in component selection, resulting in better temperature characteristics and reduced production costs. It also significantly reduces the possibility of detection failure due to environmental changes, which is particularly important for residual current devices (RCDs).

[0053] It should also be noted that the present invention is equipped with a temperature compensation module U4, which introduces a temperature compensation generation circuit. As the temperature rises, the output voltage of the temperature compensation module U4 rises accordingly, thereby adjusting the reference voltage according to the temperature. Since the output of the current amplification circuit module U2 also rises with the temperature, the temperature compensation module U4 can prevent the trigger comparator IC3 from tripping due to unreasonable temperature rise.

[0054] Furthermore, to accommodate parts from different manufacturers and batches, the digital voltage source module (DAC) also includes a correction circuit, which is equipped with:

[0055] The storage circuit provides a correction digital value based on the device parameters and experimental data, and stores the correction digital value in advance.

[0056] The digital-to-analog converter circuit has its input terminal connected to the output terminal of the storage circuit. The digital-to-analog converter circuit can convert the corrected digital value of the storage circuit into an analog voltage. After voltage accumulation by the temperature compensation filter circuit and the temperature compensation generator circuit, the voltage is used as the output terminal out of this stage circuit.

[0057] It should be noted that, due to differences in materials, processing techniques, models, specifications, and parameters among the purchased components, this invention can adjust the components based on their parameters and experimental data. For example, the magnetic ring CH in a magnetic ring coil can affect various parameters, such as magnetic induction intensity, because the material composition of the magnetic ring varies from manufacturer to manufacturer. The winding position, number of turns, and tightness of the coil also affect the parameters of the magnetic ring coil. Based on various factors such as different materials, different manufacturers' products, and the design and processing, compensation data can be obtained through experiments. This data is stored in a storage circuit, which can accurately correct the compensation circuit. The storage circuit can use an EEPROM for easy modification and can store multiple sets of data for different products. The appropriate set of stored data can be selected as needed, thus effectively improving product consistency.

[0058] Preferably, the digital-to-analog converter circuit includes:

[0059] The first switch K1, the second switch K2, ..., the Nth switch KN are connected to the power supply E via resistors R81, R82, ..., RN and R80 respectively. The other output terminal of the first switch K1, the second switch K2, ..., the Nth switch KN is grounded. The control terminals of the first switch K1, the second switch K2, ..., the Nth switch KN are connected to the output terminals D0, D1, ..., DN of the storage circuit respectively. It should be noted that MOSFETs are preferred for switching because they consume less power. The number of switches N can be four or eight. The more switches, the higher the accuracy.

[0060] Furthermore, the voltage accumulation circuit includes:

[0061] Amplifier IC4 has its positive input terminal connected to the common connection point of resistors R81, R82...RN and R80. The output terminal of amplifier IC4 is connected to the negative input terminal of amplifier IC4 in one way and to the output terminal out of digital voltage source module DAC through resistor R91 in the other way.

[0062] Amplifier IC5 has its positive input terminal as the first input terminal in1 of the digital voltage source module DAC. One output terminal of amplifier IC5 is connected to the negative input terminal of amplifier IC5, and the other output terminal out of the digital voltage source module DAC is connected through resistor R92.

[0063] The positive input terminal of amplifier IC6 serves as the second input terminal in2 of the digital voltage source module DAC. One output terminal of amplifier IC6 is connected to the negative input terminal of amplifier IC6, and the other output terminal out of the digital voltage source module DAC is connected through resistor R93.

[0064] This invention provides compensation through three-way cumulative compensation. The introduction of this three-way cumulative compensation addresses the impact of three types of deviations: the first addresses detection deviations caused by the inconsistency of components such as current transformer resistors and capacitors; the second, DC compensation addresses detection deviations caused by the DC component of leakage current; and the third, temperature compensation addresses detection deviations caused by component temperature drift. The three compensations are cumulatively added at a certain ratio, reducing the errors in the detection results caused by these three factors.

[0065] The temperature compensation filter circuit includes:

[0066] Resistor R6 has one end connected to the output terminal of current amplifier circuit module U2, and the other end connected to ground through capacitor C2. The connection point of resistor R6 and capacitor C2 is connected to the first input terminal in1 of digital voltage source module DAC.

[0067] The temperature compensation generation circuit includes:

[0068] The negative temperature coefficient thermistor RT has one path connected to the power supply E and the other path connected to ground via resistor R7. The connection point between the thermistor RT and resistor R7 is connected to the second input terminal in2 of the digital voltage source module DAC.

[0069] Preferably, the current amplifier circuit module U2 includes:

[0070] In amplifier circuit IC1, one output terminal of coil L1 is connected to the negative input terminal of amplifier circuit IC1, and the other is connected to ground via resistor R1. The other output terminal of coil L1 is connected to the positive input terminal of IC1 via resistor R3. The positive input terminal of IC1 is also connected to ground via resistor R2. The output terminal of amplifier circuit IC1 serves as the output terminal of this stage of the circuit.

[0071] It should be noted that the current amplifier circuit module U2 has multiple operating modes. This invention selects an oscillation circuit as the current amplifier circuit, which has the characteristics of high sensitivity and circuit stability.

[0072] The magnetic ring coil is used as a current transformer. In this circuit, the coil acts as an inductive element to cause the circuit to oscillate. The initial current causes changes in the parameters of the current transformer, which in turn causes changes in the output frequency and duty cycle of the oscillation signal. The leakage current on the initial side can be deduced from this. Compared with the induced current of traditional current transformers, its advantages are that it can directly detect DC current and has a high amplification factor, which can detect extremely small current signals.

[0073] To ensure seamless integration with subsequent circuitry, the current amplifier module U2 also includes:

[0074] Amplifier IC2 has two input terminals: one connected to ground via filter capacitor C1, and the other connected to the output of amplifier IC1 via resistor R4. Resistor R4 and filter capacitor C1 form a low-pass filter. One output of amplifier IC2 is connected to its negative output, and the other serves as the output of this current amplifier module U2. Amplifier IC2 is configured as an emitter follower circuit, characterized by high input impedance, low output impedance, and strong current amplification, allowing for good connection between the preceding and following stages. Operational amplifiers (op-amps) are used for both amplifier IC1 and amplifier IC2.

[0075] The comparator circuit module U5 includes: a comparator circuit IC3, the negative input terminal of the comparator circuit IC3 is connected to the output terminal of the amplifier circuit IC2, the positive input terminal of the comparator circuit IC3 is connected to the output terminal of the temperature compensation module U4, and the output terminal of the comparator circuit IC3 serves as the output terminal of the comparator circuit module U5.

[0076] The input terminal of the drive circuit module P is connected to the output terminal of the comparator circuit module U5. The output terminal of the drive circuit module P can drive the trip unit to disconnect the live wire and the neutral wire to supply power to the load. The drive circuit module P and the trip unit can be selected from existing technologies.

[0077] An integrated circuit chip for a type B leakage current protection circuit includes a current amplification circuit module U2, a temperature compensation module U4, and a comparator circuit module U5, all included in a type B leakage current protection circuit. Because the current amplification circuit module U2, temperature compensation module U4, and comparator circuit module U5 of this product are very suitable for manufacturing integrated circuit chips, they can significantly reduce size, lower energy consumption, and exhibit good consistency.

[0078] Furthermore, a type B residual current device includes a type B residual current protection circuit and an integrated circuit chip for the type B residual current protection circuit.

Claims

1. A type B leakage current protection circuit, characterized in that, include: The leakage current sampling module U1 is equipped with a magnetic ring coil. The magnetic ring CH in the magnetic ring coil can pass through the live wire L and the neutral wire N. The coil L1 in the magnetic ring coil can sense the leakage current difference between the live wire L and the neutral wire N, and output the leakage current difference to the next stage circuit. The current amplifier circuit module U2 outputs an oscillating current with an adjustable duty cycle, and the duty cycle is modulated by the difference between the coil L1 and the leakage current it induced. Temperature compensation module U4 includes: temperature compensation filter circuit, temperature compensation generator circuit and digital voltage source module DAC; The temperature compensation filter circuit has its input terminal connected to the output terminal of the current amplifier circuit module U2, and its output terminal outputs the filtered voltage signal. The temperature compensation generating circuit outputs a compensation voltage that is positively correlated with the ambient temperature. The digital voltage source module DAC has its first input terminal in1 connected to the output terminal of the temperature compensation filter circuit, and its second input terminal in2 connected to the output terminal of the temperature compensation generator circuit. The digital voltage source module DAC is equipped with a voltage accumulation circuit, which can accumulate the voltages output by the temperature compensation filter circuit and the temperature compensation generator circuit and use them as the output terminal out of this stage circuit. The input terminal of the comparator circuit module U5 is connected to the output terminal of the current amplifier circuit module U2 and the output terminal of the digital voltage source module DAC, respectively. When the leakage current difference exceeds a predetermined value, the control voltage is output. The input terminal of the drive circuit module P is connected to the output terminal of the comparator circuit module U5. The output terminal of the drive circuit module P is connected to the trip unit. When the output terminal of the comparator circuit module U5 outputs a control voltage, the drive circuit module P can cause the trip unit to operate, ultimately disconnecting the live wire and / or neutral wire to supply power to the load.

2. The type B leakage current protection circuit as described in claim 1, characterized in that, The digital voltage source module (DAC) also includes a correction circuit, which is configured with: The storage circuit provides a correction digital value based on the device parameters and experimental data, and stores the correction digital value in advance. The digital-to-analog converter circuit has its input terminal connected to the output terminal of the storage circuit. The digital-to-analog converter circuit can convert the corrected digital value of the storage circuit into an analog voltage, and after voltage accumulation with the temperature compensation filter circuit and the temperature compensation generator circuit, it becomes the output terminal out of this stage circuit.

3. The type B leakage current protection circuit as described in claim 2, characterized in that: The aforementioned digital-to-analog converter circuit includes: The first switch K1, the second switch K2, ... the Nth switch KN, one output terminal of the first switch K1, the second switch K2, ... the Nth switch KN is connected to the power supply E through resistors R81, R82 ... RN and R80 respectively. The other output terminal of the first switch K1, the second switch K2, ... the Nth switch KN is grounded. The control terminals of the first switch K1, the second switch K2, ... the Nth switch KN are respectively connected to the output terminals D0, D1 ... DN of the storage circuit. The voltage accumulation circuit includes: Amplifier IC4 has its positive input terminal connected to the common connection point of resistors R81, R82...RN and R80. The output terminal of amplifier IC4 is connected to the negative input terminal of amplifier IC4 in one way and to the output terminal out of the digital voltage source module DAC through resistor R91 in the other way. Amplifier IC5 has its positive input terminal serving as the first input terminal in1 of the digital voltage source module DAC. One output terminal of amplifier IC5 is connected to the negative input terminal of amplifier IC5, and the other output terminal is connected to the output terminal out of the digital voltage source module DAC via resistor R92. The positive input terminal of amplifier IC6 serves as the second input terminal in2 of the digital voltage source module DAC. One output terminal of amplifier IC6 is connected to the negative input terminal of amplifier IC6, and the other output terminal out of the digital voltage source module DAC is connected through resistor R93.

4. A type B leakage current protection circuit as described in any one of claims 1-3, characterized in that: The temperature compensation filter circuit includes: Resistor R6 has one end connected to the output terminal of current amplifier circuit module U2 and the other end connected to ground via capacitor C2. The connection point of resistor R6 and capacitor C2 is connected to the first input terminal in1 of the digital voltage source module DAC. The temperature compensation generating circuit includes: The negative temperature coefficient thermistor RT has one path connected to the power supply E and the other path connected to ground via resistor R7. The connection point between the thermistor RT and resistor R7 is connected to the second input terminal in2 of the digital voltage source module DAC.

5. A type B leakage current protection circuit as described in any one of claims 1-4, characterized in that: The current amplifier circuit module U2 includes: In amplifier circuit IC1, one output terminal of coil L1 is connected to the negative input terminal of amplifier circuit IC1, and the other is connected to ground via resistor R1. The other output terminal of coil L1 is connected to the positive input terminal of IC1 via resistor R3. The positive input terminal of IC1 is also connected to ground via resistor R2. The output terminal of amplifier circuit IC1 serves as the output terminal of this stage circuit.

6. A type B leakage current protection circuit as described in claim 5, characterized in that, The current amplifier circuit module U2 also includes: Amplifier IC2 has two input terminals: one is grounded via filter capacitor C1, and the other is connected to the output terminal of amplifier IC1 via resistor R4; the other output terminal of amplifier IC2 is connected to the negative output terminal of amplifier IC2, and the other is also used as the output terminal of this current amplifier circuit module U2.

7. A type B leakage current protection circuit as described in claim 6, characterized in that: The comparison circuit module U5 includes: a comparison circuit IC3, the negative input terminal of the comparison circuit IC3 is connected to the output terminal of the amplifier circuit IC2, the positive input terminal of the comparison circuit IC3 is connected to the output terminal of the temperature compensation module U4, and the output terminal of the comparison circuit IC3 serves as the output terminal of the comparison circuit module U5.

8. A type B leakage current protection circuit as described in claim 7, characterized in that: The drive circuit module P has its input terminal connected to the output terminal of the comparator circuit module U5. The output terminal of the drive circuit module P can drive the trip unit to disconnect the live wire and the neutral wire to supply power to the load.

9. An integrated circuit chip for a type B leakage current protection circuit, characterized in that, It includes the current amplification circuit module U2, the temperature compensation module U4, and the comparator circuit module U5 contained in the type B leakage protection circuit as described in any one of claims 1-8.

10. A type B residual current device, characterized in that, It includes the type B leakage current protection circuit as described in any one of claims 1-8, and also includes the integrated circuit chip of the type B leakage current protection circuit as described in claim 9.

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