eFuse control circuit, eFuse control system and its testing methods

Abstract

This invention discloses an eFuse control circuit, an eFuse control system, and a testing method thereof. The eFuse control circuit, used to output calibration data to a controlled unit, includes: a data output module, an eFuse module, and a multiplexer. The output terminal of the data output module is connected to the first input terminal of the multiplexer and configured to output pre-calibration data to the first input terminal of the multiplexer; wherein the data in the data output module is rewritable. The output terminal of the eFuse module is connected to the second input terminal of the multiplexer and configured to write calibration data determined by testing. The output terminal of the multiplexer is used to connect to the controlled unit, and the multiplexer is configured to connect its first input terminal to its output terminal, or its second input terminal to its output terminal. This invention improves the flexibility of the eFuse control circuit and reduces testing costs.

Description

Technical Field

[0001] This invention relates to the field of eFuse technology, and in particular to an eFuse control circuit, an eFuse control system, and a testing method thereof. Background Technology

[0002] eFuse, or one-time programmable memory, is a structure that uses an electric current to burn out a fuse, thereby permanently writing data. eFuse can be used to store permanent information and has important applications in the field of modern electronics.

[0003] The existing eFuse structure can only be used to directly control the controlled unit, and once programmed, it cannot be modified. However, testing may require multiple data adjustments, and using the existing eFuse structure necessitates replacing the eFuse, significantly increasing testing costs. Summary of the Invention

[0004] This invention provides an eFuse control circuit, an eFuse control system, and a testing method thereof, in order to improve the flexibility of the eFuse control circuit and reduce testing costs.

[0005] According to one aspect of the present invention, an eFuse control circuit is provided for outputting calibration data to a controlled unit, the eFuse control circuit comprising: a data output module, an eFuse module, and a multiplexer;

[0006] The output terminal of the data output module is connected to the first input terminal of the multiplexer, and the data output module is configured to output pre-calibration data to the first input terminal of the multiplexer; wherein, the data in the data output module can be repeatedly erased and rewritten;

[0007] The output of the eFuse module is connected to the second input of the multiplexer, and the eFuse module is configured to write calibration data determined by the test.

[0008] The output of the multiplexer is used to connect to the controlled unit, and the multiplexer is configured to connect its first input to its output, or its second input to its output.

[0009] Optionally, the output terminal of the data output module is connected to the data writing terminal of the eFuse module, and the data output module is further configured to write the calibration data determined by the test to the eFuse module.

[0010] Optionally, the data output module is a register.

[0011] Optionally, the eFuse module includes multiple eFuse units, each of the eFuse units including:

[0012] The eFuse is used to blow the fuse when the fuse current is within a preset fuse current range in order to record data; the read / write NMOS is connected to the eFuse and configured to be turned on during programming and turned off during data reading.

[0013] Optionally, the eFuse control circuit further includes a controller;

[0014] The controller is connected to the selection terminal of the multiplexer. The controller is configured to output a first selection signal to the selection terminal of the multiplexer to connect the first input terminal of the multiplexer to its output terminal; or, to output a second selection signal to the selection terminal of the multiplexer to connect the second input terminal of the multiplexer to its output terminal.

[0015] Optionally, the controller is further configured to lock its output data as the second selection signal after the test of the controlled unit is completed.

[0016] According to another aspect of the present invention, an eFuse control system is provided, the eFuse control system including the above-described eFuse control circuit and the controlled unit;

[0017] The output of the multiplexer is connected to the controlled unit.

[0018] Optionally, the controlled unit includes a processor, an analog-to-digital converter, or an analog front-end chip.

[0019] According to another aspect of the present invention, a test method for an eFuse control system is provided for testing the above-described eFuse control system, the test method for the eFuse control system comprising:

[0020] The data output module outputs pre-calibration data to the first input terminal of the multiplexer and controls the first input terminal of the multiplexer to be connected to its output terminal so as to write the pre-calibration data into the controlled unit.

[0021] The pre-calibration data corresponding to when the controlled unit reaches the preset requirements is used as the calibration data determined by the test;

[0022] The calibration data determined by the test is written into the eFuse module, and the second input terminal of the multiplexer is controlled to be connected to its output terminal.

[0023] Optionally, the output terminal of the data output module is connected to the data writing terminal of the eFuse module;

[0024] Writing the calibration data determined by the test into the eFuse module includes:

[0025] The calibration data determined by the test is written to the eFuse module through the data output module.

[0026] The technical solution of this invention employs an eFuse control circuit for outputting calibration data to a controlled unit. The eFuse control circuit includes a data output module, an eFuse module, and a multiplexer. The output terminal of the data output module is connected to the first input terminal of the multiplexer, and the data output module is configured to output pre-calibration data to the first input terminal of the multiplexer. The data in the data output module is rewritable. The output terminal of the eFuse module is connected to the second input terminal of the multiplexer, and the eFuse module is configured to write calibration data determined by the test. The output terminal of the multiplexer is connected to the controlled unit, and the multiplexer is configured to connect its first input terminal to its output terminal, or its second input terminal to its output terminal. During testing, pre-calibration data can be output to the controlled unit through the data output module. The data in the data output module is rewritable, providing greater flexibility. Furthermore, it eliminates the need to replace the eFuse module after each test, significantly reducing costs. After the test, calibration data is written to the eFuse module, and the eFuse module outputs calibration data to the controlled unit, greatly improving the accuracy of the output calibration data.

[0027] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A schematic diagram of the circuit structure of an eFuse control circuit provided in an embodiment of the present invention;

[0030] Figure 2 A schematic diagram of the circuit structure of another eFuse control circuit provided in an embodiment of the present invention;

[0031] Figure 3 A schematic diagram of the circuit structure of another eFuse control circuit provided in an embodiment of the present invention;

[0032] Figure 4 A schematic diagram of the circuit structure of an eFuse unit provided in an embodiment of the present invention;

[0033] Figure 5 A schematic diagram of the circuit structure of another eFuse control circuit provided in an embodiment of the present invention;

[0034] Figure 6 A schematic diagram of the circuit structure of an eFuse control system provided in an embodiment of the present invention;

[0035] Figure 7 A flowchart of a testing method for an eFuse control system provided in an embodiment of the present invention. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] Figure 1 This is a schematic diagram of the circuit structure of an eFuse control circuit provided in an embodiment of the present invention, with reference to... Figure 1The eFuse control circuit is used to output calibration data to the controlled unit. The eFuse control circuit includes: a data output module 11, an eFuse module 12, and a multiplexer 13. The output terminal of the data output module 11 is connected to the first input terminal A of the multiplexer 13. The data output module 11 is configured to output pre-calibration data to the first input terminal of the multiplexer 13. The data in the data output module 11 can be repeatedly erased and rewritten. The output terminal DO of the eFuse module 12 is connected to the second input terminal B of the multiplexer 13. The eFuse module 12 is configured to write calibration data determined by testing. The output terminal of the multiplexer 13 is used to connect to the controlled unit. The multiplexer 13 is configured to connect its first input terminal A to its output terminal, or its second input terminal B to its output terminal.

[0039] Specifically, the controlled unit can be, for example, a processor, an analog-to-digital converter, or an analog front-end chip. Before leaving the factory, the controlled unit needs to have its internal data calibrated. During testing, due to various reasons, such as immature calibration algorithms or differences in chip manufacturing processes, the controlled unit often needs to undergo multiple calibrations. During calibration, pre-calibration data can be written into the data output module 11, and then the data output module 11 can be used to input the pre-calibration data to the first input terminal of the multiplexer 13. At this time, the selection terminal SEL of the multiplexer 13 is set to the first selection signal, making the first input terminal and output terminal of the multiplexer 13 connected. That is, during the pre-shipment R&D testing phase, the data output module 11 is used to write pre-calibration data to the controlled unit to determine whether the controlled unit has been successfully calibrated. If the calibration is successful, it indicates that the current pre-calibration data can be used as the calibration data after leaving the factory. If the calibration is unsuccessful, the value of the pre-calibration data can be changed, and the updated pre-calibration data can be written into the data output module 11. The new pre-calibration data is then used to calibrate the controlled unit until the calibration is successful. After successful calibration by the control unit, in order to prevent the calibration data from being tampered with, the calibration data is written into the eFuse module 12 during the pre-shipment calibration, and the selection terminal SEL of the multiplexer 13 is set as the second selection signal, so that the second input terminal of the multiplexer 13 is connected to its output terminal. That is, after leaving the factory, the eFuse module 12 is used to output calibration data to the control unit, so that the control unit can receive accurate calibration data.

[0040] The technical solution of this embodiment employs an eFuse control circuit for outputting calibration data to the controlled unit. The eFuse control circuit includes a data output module, an eFuse module, and a multiplexer. The output terminal of the data output module is connected to the first input terminal of the multiplexer, and the data output module is configured to output pre-calibration data to the first input terminal of the multiplexer. The data in the data output module is rewritable. The output terminal of the eFuse module is connected to the second input terminal of the multiplexer, and the eFuse module is configured to write calibration data determined by the test. The output terminal of the multiplexer is connected to the controlled unit, and the multiplexer is configured to either connect its first input terminal to its output terminal or its second input terminal to its output terminal. During testing, pre-calibration data can be output to the controlled unit through the data output module. The data in the data output module is rewritable, providing greater flexibility. Furthermore, it eliminates the need to replace the eFuse module after each test, significantly reducing costs. After the test, calibration data is written to the eFuse module, and the eFuse module outputs calibration data to the controlled unit, greatly improving the accuracy of the output calibration data.

[0041] Optionally, Figure 2 This is a schematic diagram of the circuit structure of another eFuse control circuit provided in an embodiment of the present invention, with reference to... Figure 2 The output terminal of the data output module 11 is connected to the data writing terminal DI of the eFuse module 12. The data output module 11 is also configured to write the calibration data determined by the test to the eFuse module.

[0042] Specifically, in this embodiment, the output terminal of the data output module 11 can directly write data to the data writing terminal DI of the eFuse module. It can be understood that after the test, there is no need to use other modules to write data to the eFuse module 12; the data output module 11 can directly write data to the eFuse module 12, which greatly simplifies the circuit structure. It should be noted that the data written to the eFuse module 12 can be configured with a special format to prevent pre-calibration data written to the multiplexer 13 during testing from being written to the eFuse module 12. Alternatively, a switching unit can be set between the data output module 11 and the data writing terminal DI of the eFuse module 12. During the test, the switching unit is disconnected to prevent pre-calibration data from being written to the eFuse module; after the test, the switching unit is turned on, thereby allowing the data output module 11 to write calibration data to the eFuse module 12.

[0043] Optionally, Figure 3 This is a schematic diagram of the circuit structure of another eFuse control circuit provided in an embodiment of the present invention, with reference to... Figure 3The data output module is register 111. Register 111 can be composed of multiple flip-flops. This embodiment of the invention does not impose a specific limit on the number of flip-flops included in register 111, as long as the pre-calibration data can be completely written to the multiplexer and the calibration data can be completely written to the eFuse module. Register 111 can be a parallel input or a serial input, and the output can be a parallel output or a serial output. The specific circuit structure of register 111 is well known to those skilled in the art and will not be described in detail here.

[0044] Optionally, Figure 4 This is a circuit structure diagram of an eFuse unit provided in an embodiment of the present invention. The eFuse module includes multiple eFuse units, each eFuse unit including:

[0045] eFuse 121 is used to blow the fuse when the fuse current is within the preset fuse current range to record data; NMOS 122, which is connected to eFuse 121, is configured to be turned on when programming and turned off when reading data.

[0046] Specifically, such as Figure 4 As shown, the first terminal of eFuse 121 is connected to a fixed voltage VP, and the second terminal is electrically connected to the first terminal of read / write NMOS 122; the second terminal of read / write NMOS 122 is grounded, and the control terminal of read / write NMOS 122 is connected to the programming voltage Vg; the second terminal Vsense of eFuse 121 serves as the output terminal of the eFuse cell. When the programming voltage Vg is high, the read / write NMOS is turned on, allowing programming current to flow through eFuse 121 to ground. A typical programming current is 10 mA, and the on-time of read / write NMOS 122 can be greater than 200 microseconds. The eFuse burns out under the influence of the programming current, thus changing from a small resistor to a large resistor, completing the data programming process. When programming is complete and data needs to be read, the programming voltage Vg is set to low, the read / write NMOS is turned off, and the magnitude of the Vsense voltage can be read to determine whether the eFuse cell has been programmed, i.e., whether the data stored in the eFuse cell is 0 or 1. Typically, for example, programmed values ​​are 1 and unprogrammed values ​​are 0; of course, it can also be programmed values ​​are 0 and unprogrammed values ​​are 1.

[0047] Optionally, Figure 5 This is a schematic diagram of the circuit structure of another eFuse control circuit provided in an embodiment of the present invention, with reference to... Figure 5The eFuse control circuit also includes a controller 14; the controller 14 is connected to the selection terminal SEL of the multiplexer 13, and the controller 14 is configured to output a first selection signal to the selection terminal SEL of the multiplexer 13 to connect the first input terminal of the multiplexer 13 to its output terminal; or output a second selection signal to the selection terminal SEL of the multiplexer 13 to connect the second input terminal of the multiplexer 13 to its output terminal.

[0048] Specifically, the controller 14 may be, for example, a microprocessor. During the calibration process, the data output module 11 inputs pre-calibration data to the first input terminal of the multiplexer 13. At this time, the controller 14 controls the selection terminal SEL of the multiplexer 13 to be the first selection signal, so that the first input terminal and the output terminal of the multiplexer 13 are connected. That is, in the R&D testing stage before leaving the factory, the data output module 11 writes pre-calibration data to the control unit to determine whether the control unit is calibrated successfully. If the calibration is successful, it means that the current pre-calibration data can be used as the calibration data after leaving the factory. If the calibration is unsuccessful, the value of the pre-calibration data can be changed, the updated pre-calibration data can be written into the data output module 11, and the control unit can be calibrated using the new pre-calibration data until the calibration is successful. After successful calibration by the control unit, in order to prevent the calibration data from being tampered with, the calibration data is written into the eFuse module 12 during the pre-shipment calibration, and the controller 14 sets the selection terminal SEL of the multiplexer 13 to the second selection signal, so that the second input terminal of the multiplexer 13 is connected to its output terminal. That is, after leaving the factory, the eFuse module 12 outputs the calibration data to the control unit, so that the control unit can receive accurate calibration data.

[0049] Preferably, the controller 14 is further configured to lock the output data of the controlled unit as a second selection signal after the test is completed.

[0050] Specifically, after the test is completed, the register no longer needs to output data to the control unit. To prevent the output of the multiplexer 13 from being connected to its first input after the test, which would cause the control unit to receive incorrect data, this embodiment uses a controller to lock the data at the control terminal of the multiplexer. That is, the selection terminal of the multiplexer 13 always receives the second selection signal, ensuring that the output of the multiplexer 13 is always connected to the second input.

[0051] This invention also provides an eFuse control system. Figure 6 This is a circuit structure diagram of an eFuse control system provided in an embodiment of the present invention, with reference to... Figure 6The eFuse control system includes the eFuse control circuit and the controlled unit 20 provided in any embodiment of the present invention; the output terminal of the multiplexer is connected to the controlled unit 20. When testing the controlled unit, the eFuse control system can output a pre-calibration signal to the controlled unit 20 via the data output module; after the test is completed, the eFuse module outputs a calibration signal to the controlled unit 20. Since the eFuse control system provided in this embodiment includes the eFuse control circuit provided in any embodiment of the present invention, it also has the same beneficial effects, and will not be described further here.

[0052] For example, the control unit 20 includes a processor, an analog-to-digital converter, or an analog front-end chip. Pre-calibration data and calibration data may include chip version information, offset voltage, gain, or current magnitude, etc.

[0053] This invention also provides a testing method for an eFuse control system, such as... Figure 7 As shown, Figure 7 A flowchart illustrating a testing method for an eFuse control system provided in an embodiment of the present invention; the testing method includes:

[0054] Step S110: Output pre-calibration data to the first input terminal of the multiplexer through the data output module, and control the first input terminal of the multiplexer to be connected to its output terminal so as to write the pre-calibration data into the control unit.

[0055] Step S120: The pre-calibration data corresponding to when the control unit reaches the preset requirements is used as the calibration data determined by the test;

[0056] Step S130: Write the calibration data determined by the test into the eFuse module and control the second input terminal of the multiplexer to be connected to its output terminal.

[0057] Specifically, during the calibration process, pre-calibration data can be written into the data output module first, and then used to input the pre-calibration data to the first input terminal of the multiplexer, controlling the first input terminal and output terminal of the multiplexer to conduct. That is, during the pre-shipment R&D testing phase, the data output module is used to write pre-calibration data to the controlled unit. Subsequently, it is determined whether the controlled unit has been successfully calibrated. If the calibration is successful (i.e., the controlled unit has reached a preset state), the current pre-calibration data can be used as the calibration data after shipment (i.e., the calibration data determined by testing). If the calibration is unsuccessful, the value of the pre-calibration data can be changed, and the updated pre-calibration data can be written into the data output module. The new pre-calibration data is then used to calibrate the controlled unit until successful. After successful calibration of the controlled unit, to prevent tampering with the calibration data, the calibration data is written into the eFuse module during pre-shipment calibration, and the selector terminal SEL of the multiplexer is set to the second select signal, making the second input terminal of the multiplexer conduct with its output terminal. That is, after shipment, the eFuse module is used to output calibration data to the controlled unit, ensuring that the controlled unit receives accurate calibration data.

[0058] The technical solution of this embodiment employs a testing method that allows pre-calibration data to be output to the controlled unit via a data output module during testing. The data in the data output module can be repeatedly erased and rewritten, offering greater flexibility. Furthermore, it eliminates the need to replace the eFuse module after each test, significantly reducing costs. After the test, calibration data is written to the eFuse module, and the eFuse module outputs calibration data to the controlled unit, greatly improving the accuracy of the output calibration data.

[0059] Optionally, the output end of the data output module is connected to the data writing end of the eFuse module; writing the calibration data determined by the test into the eFuse module includes: writing the calibration data determined by the test into the eFuse module through the data output module. The output end of the data output module can directly write data into the data writing end of the eFuse module; after the test, there is no need to use other modules to write data into the eFuse module, and data can be directly written into the eFuse module using the data output module, which can greatly simplify the test process.

[0060] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0061] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An eFuse control circuit for outputting calibration data to a controlled unit, characterized in that, The eFuse control circuit includes: a data output module, an eFuse module, and a multiplexer; The output terminal of the data output module is connected to the first input terminal of the multiplexer, and the data output module is configured to output pre-calibration data to the first input terminal of the multiplexer; wherein, the data in the data output module can be repeatedly erased and rewritten; The output of the eFuse module is connected to the second input of the multiplexer, and the eFuse module is configured to write calibration data determined by the test. The output terminal of the multiplexer is used to connect to the controlled unit. The multiplexer is configured to connect the first input terminal of the multiplexer to the output terminal of the multiplexer, or to connect the second input terminal of the multiplexer to the output terminal of the multiplexer. The pre-calibration data and the calibration data are chip version information, offset voltage, gain, or current magnitude.

2. The eFuse control circuit according to claim 1, characterized in that, The output terminal of the data output module is connected to the data writing terminal of the eFuse module, and the data output module is further configured to write the calibration data determined by the test to the eFuse module.

3. The eFuse control circuit according to claim 1, characterized in that, The data output module is a register.

4. The eFuse control circuit according to claim 1, characterized in that, The eFuse module includes multiple eFuse units, and each eFuse unit includes: The eFuse is used to blow the fuse when the fuse current is within a preset fuse current range in order to record data; the read / write NMOS is connected to the eFuse and configured to be turned on during programming and turned off during data reading.

5. The eFuse control circuit according to claim 1, characterized in that, The eFuse control circuit also includes a controller; The controller is connected to the selection terminal of the multiplexer. The controller is configured to output a first selection signal to the selection terminal of the multiplexer to connect the first input terminal of the multiplexer to its output terminal, or to output a second selection signal to the selection terminal of the multiplexer to connect the second input terminal of the multiplexer to its output terminal.

6. The eFuse control circuit according to claim 5, characterized in that, The controller is also configured to lock its output data as the second selection signal after the test of the controlled unit is completed.

7. An eFuse control system, characterized in that, The eFuse control system includes the eFuse control circuit and the controlled unit as described in any one of claims 1-6; The output of the multiplexer is connected to the controlled unit.

8. The eFuse control system according to claim 7, characterized in that, The controlled unit includes: a processor, an analog-to-digital converter, or an analog front-end chip.

9. A test method for an eFuse control system, used to test the eFuse control system according to claim 7 or 8, characterized in that, The testing methods for the eFuse control system include: The data output module outputs pre-calibration data to the first input terminal of the multiplexer and controls the first input terminal of the multiplexer to be connected to its output terminal so as to write the pre-calibration data into the controlled unit. The pre-calibration data corresponding to when the controlled unit reaches the preset requirements is used as the calibration data determined by the test; The calibration data determined by the test is written into the eFuse module, and the second input terminal of the multiplexer is controlled to be connected to its output terminal.

10. The test method for the eFuse control system according to claim 9, characterized in that, The output terminal of the data output module is connected to the data writing terminal of the eFuse module; Writing the calibration data determined by the test into the eFuse module includes: The calibration data determined by the test is written to the eFuse module through the data output module.

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