JP5276873B2 - Semiconductor circuit and trimming method - Google Patents

Description

  The present invention relates to a semiconductor circuit including a trimming circuit and a method for trimming the semiconductor circuit.

  In the manufacture of semiconductor circuits, in order to adjust the characteristic variation due to process variations, trimming is often performed in a test process to match the characteristics. However, once trimming cannot be restored, the same characteristics as when trimming was performed before trimming were temporarily measured during testing (hereinafter referred to as provisional trimming), and predetermined after trimming It is performed to prevent the above characteristics from being obtained.

  FIG. 6 is a schematic diagram of a semiconductor circuit capable of temporary trimming described in Patent Document 1 when the number of bits of the trimming pattern is 3 bits. Trimming circuits 1A, 1B, and 1C that have a cuttable wiring and whose characteristics can be adjusted depending on whether the wiring is cut, a shift register circuit 12, and a selector circuit 11 that includes switches 11A, 11B, and 11C. It is composed of a circuit to be adjusted 4.

  The operation of this circuit will be described. In the following description, high level signal = 1 and low level signal = 0. At the time of normal operation, the selector control input terminal / clock input terminal is selected so that the switch 11A selects the output O1A of the trimming circuit 1A, the switch 11B selects the output O1B of the trimming circuit 1B, and the switch 11C selects the output O1C of the trimming circuit 1C. The selector control signal is input from 14, and the circuit to be adjusted 4 is adjusted according to the trimming states (cutting / non-cutting of wiring) of the trimming circuits 1A, 1B, and 1C.

  At the time of the test, the selector control input terminal / clock is selected so that the switch 11A selects the output O12A of the shift register circuit 12, the switch 11B selects the output O12B of the shift register circuit 12, and the switch 11C selects the output O12C of the shift register circuit 12. A trimming clock is input from the input terminal 14.

  By inputting the trimming data from the trimming data input terminal 13 and the trimming clock from the selector control input terminal / clock input terminal 14 and changing the set values of the outputs O12A, O12B and O12C of the shift register circuit 12, The circuit to be adjusted 4 is adjusted.

  During this adjustment, a trimming pattern in which the characteristics of the circuit to be adjusted 4 fall within a specified value is found, and trimming is performed using this trimming pattern. For example, when the set value of each output of the shift register circuit 12 is (O12C, O12B, O12A) = (1, 0, 0) and the characteristics of the circuit to be adjusted 4 enter a specified value, the trimming circuit 1C, Trimming is performed so that the outputs of 1B and 1A are (O1C, O1B, O1A) = (1, 0, 0).

  FIG. 7 is a schematic diagram of a semiconductor circuit capable of provisional trimming described in Patent Document 2 when the number of bits of the trimming pattern is 3 bits. A selector circuit 11 having trimming circuits 1A, 1B, and 1C, register circuits 15A, 15B, and 15C, and switches 11A, 11B, and 11C that have a cuttable wiring and whose characteristics can be adjusted depending on whether or not the wiring is cut. The adjustment circuit 4 is configured.

  The operation of this circuit will be described. During normal operation, the selector 11 is controlled by the selector control input terminal 9 so that the switch 11A selects the output O1A of the trimming circuit 1A, the switch 11B selects the output O1B of the trimming circuit 1B, and the switch 11C selects the output O1C of the trimming circuit 1C. A signal is input, and the circuit to be adjusted 4 is adjusted according to the trimming state of the trimming circuits 1A, 1B, and 1C.

  During the test, the selector control input terminal 9 selects the selector control signal so that the switch 11A selects the output O15A of the register circuit 15A, the switch 11B selects the output O15B of the register circuit 15B, and the switch 11C selects the output O15C of the register circuit 15C. Is entered.

  Trimming data is input from the trimming data input terminals 13A, 13B, and 13C, a trimming clock is input from the clock input terminal 16, and the set values of the outputs O15A, O15B, and O15C of the register circuits 15A, 15B, and 15C are changed. Thus, the adjusted circuit 4 is adjusted.

During this adjustment, a trimming pattern in which the characteristics of the circuit to be adjusted 4 fall within a specified value is found and trimming is performed using this trimming pattern. For example, when the characteristics of the circuit to be adjusted 4 enter a specified value when the set values of the register circuits 15C, 15B, and 15A are (O15C, O15B, O15A) = (1, 0, 0), the trimming circuit 1C, Trimming is performed so that the outputs of 1B and 1A are (O1C, O1B, O1A) = (1, 0, 0).
JP 05-63090 A JP 2003-249562 A

  However, the circuit described in Patent Document 1 requires a trimming data input terminal for provisional trimming, which increases the number of terminals, that is, pads, and increases the chip size.

  Similarly, in the trimming circuit described in Patent Document 2, trimming data input terminals are required for the number of bits of the trimming pattern, and further, a clock input terminal for inputting a trimming clock is necessary, so that the number of terminals, that is, pads is increased. There was a problem of increasing the size.

  The present invention solves these problems, realizes a semiconductor circuit that enables temporary trimming with almost no change in chip size, and improves the test sequence to reduce defective samples and perform efficient trimming. Objective.

In order to achieve the above object, a semiconductor circuit according to a first aspect of the present invention includes n trimming circuits in which wiring is cut / uncut for adjustment of characteristics in a test step after the semiconductor process; A semiconductor circuit having an adjusted circuit to which the n trimming circuits are connected includes a selector circuit and n flip-flop circuits, and the selector circuit is set to a first mode, whereby the n Each of the trimming circuits is connected to the circuit to be adjusted via the n flip-flop circuits, and the selector circuit is set to the second mode, so that the n flip-flop circuits have n bits. A path comprising a counter circuit, and an output of the counter circuit is connected to the circuit to be adjusted.
Such inventions to claim 2, in the semiconductor circuit according to claim 1, comprising said shared input terminal is shared with a clock input terminal of the counter circuit and the input terminal of the internal circuit including the adjusted circuit, said The common input terminal functions as an input terminal of the internal circuit when the selector circuit is set in the first mode, and a clock input terminal of the counter circuit when the selector circuit is set in the second mode. that acts as a, characterized in that.
A trimming method according to a third aspect of the present invention is a trimming method using the semiconductor circuit according to the first or second aspect , wherein the trimming method using the n trimming circuits connected to the circuit to be adjusted is performed before the trimming. In a trimming method of performing temporary trimming on a circuit to be adjusted, and cutting / uncutting the wirings of the n trimming circuits according to the result of the temporary trimming,
Acquires a trimming table composed of a combination of ²ⁿ types of characteristics of the circuit to be adjusted for a plurality of the semiconductor circuits and ²ⁿ trimming patterns that match each classification characteristic within a specified value range. A trimming pattern is selected based on the trimming table in accordance with the current characteristics of the circuit to be adjusted, the trimming pattern is realized by the count value of the n-bit counter circuit, and the n-bit counter circuit The output of the counter value is connected to the circuit to be adjusted to perform temporary trimming, the characteristics of the temporarily trimmed circuit to be adjusted are measured, and when the measurement result is within the specified value range, the trimming circuit On the other hand, the wiring is cut / uncut so as to have the same trimming pattern as the temporary trimming .
According to a fourth aspect of the present invention, in the trimming method according to the third aspect, a measurement result of the characteristics of the provisionally trimmed circuit is out of the specified value range, and the n-bit counter circuit When corresponding to a trimming pattern realized with a first count value before the count value, the n-bit counter circuit is reset and then counted up to the first count value, and the output of the count value is Re-temporary trimming is performed by connecting to the circuit to be adjusted, and the characteristics of the circuit to be adjusted that has been re-temporarily trimmed are measured.When the measurement result is within the specified value range, The wiring is cut / uncut so as to have the same trimming pattern as the re-temporary trimming .
According to a fifth aspect of the present invention, in the trimming method according to the third aspect , the measurement result of the characteristics of the temporarily trimmed circuit is out of the range of the specified value, and the n-bit counter circuit When corresponding to the trimming pattern realized by the second count value exceeding the count value, the n-bit counter circuit further counts up to the second count value, and the count value of the n-bit counter circuit Connect the output to the circuit to be adjusted, perform re-temporary trimming, measure the characteristics of the re-trimmed circuit to be adjusted, and when the measurement result is within the specified value range, On the other hand, the wiring is cut / uncut so as to have the same trimming pattern as the re-temporary trimming.

  According to the first and second aspects of the present invention, the trimming data input terminal is not required, and according to the third aspect of the invention, the dedicated clock input terminal is not required, and the provisional clock input terminal is hardly changed. A circuit that enables trimming can be realized. According to the inventions according to claims 4 to 6, it is possible to reduce defective samples and perform efficient trimming.

<First embodiment>
FIG. 1 shows a semiconductor circuit according to the first embodiment of the present invention when the number of bits of a trimming pattern is 3 bits. The connection is changed by the trimming circuits 1A, 1B, and 1C having the cuttable wiring and the characteristics can be adjusted depending on whether or not the wiring is cut and the selector circuit 2 having the switches 2A, 2B, 2C, 2D, and 2E. Thus, the flip-flop circuits 3A, 3B, and 3C that can be selected as individual memory circuits or counter circuits 3 and the circuit to be adjusted 4 are configured.

  First, the operation of this circuit will be described. In the following description, high level signal = 1 and low level signal = 0. During normal operation, the clock input terminal 6 is selected for the switches 2A and 2B, the output O1A of the trimming circuit 1A is selected for the switch 2C, the output O1B of the trimming circuit 1B is selected for the switch 2D, and the output O1C of the trimming circuit 1C is selected for the selector 2E. As described above, a mode switching signal is input from the mode switching terminal 5. The flip-flop circuit 3A is a memory circuit that holds the trimming state of the trimming circuit 1A, the flip-flop circuit 3B is a memory circuit that holds the trimming state of the trimming circuit 1B, and the flip-flop circuit 3C is a memory circuit that holds the trimming state of the trimming circuit 1C. Configured as

  When one clock is input from the clock input terminal 6, the trimming states of the trimming circuits 1A, 1B, and 1C are held in flip-flop circuits 3A, 3B, and 3C as memory circuits, and the trimming circuits 1A, 1B, and The adjusted circuit 4 is adjusted by the trimming state of 1C.

  During the test, the switches 2A and 2C are switched so that the inverted output O3AX of the flip-flop circuit 3A is selected, the switches 2B and 2D are selected as the inverted output O3BX of the flip-flop circuit 3B, and the switch 2E is selected as the inverted output O3CX of the flip-flop circuit 3C. A mode switching signal is input from the terminal 5, and the flip-flop circuits 3A, 3B, 3C are configured as a 3-bit counter circuit 3.

  When the trimming clock is input from the clock input terminal 6, the counter circuit 3 counts up. That is, the adjusted circuit 4 is adjusted by changing the set values of the outputs O3A, O3B, and O3C of the counter circuit 3.

  During this adjustment, a trimming pattern in which the characteristics of the circuit to be adjusted 4 fall within a specified value is found, and trimming is performed using this trimming pattern. For example, when the characteristics of the circuit to be adjusted 4 enter a specified value when the setting value of the counter circuit 3 is (O3C, O3B, O3A) = (1, 0, 0), the trimming circuits 1C, 1B, 1A Trimming is performed so that the output becomes (O1C, O1B, O1A) = (1, 0, 0).

  FIG. 3 is a diagram for explaining a method of inputting the trimming clock of the counter circuit 3. During normal operation, the demultiplexer circuit 7 receives a mode switching signal from the mode switching terminal 5 so that the internal circuit input terminal 17 is selected, and the internal circuit input terminal / counter clock input terminal 8 is connected to the circuit 4 to be adjusted. The input terminal of the internal circuit 10 including

  At the time of the test, the demultiplexer circuit 7 receives the mode switching signal from the mode switching terminal 5 so that the clock input terminal 6 is selected, and the internal circuit input terminal / counter clock input terminal 8 is the trimming clock for the counter circuit 3. This is the clock input pin for inputting. That is, the internal circuit input terminal and the counter clock input terminal are shared.

  With the circuit configuration as described above, the trimming data input terminal and the dedicated clock input terminal for inputting the trimming clock are not required, so that the number of terminals, that is, pads, is reduced and the chip size is prevented from increasing. It becomes possible.

  The selector circuit 2 and the demultiplexer circuit 7 in the first embodiment of the present invention are not particularly limited as long as they have the same function in addition to the analog switch composed of MOS transistors. The memory circuit / counter circuit 3 is not limited to the D flip-flop as long as it has the same function. The trimming circuits 1 </ b> A to 1 </ b> C are not limited in circuit configuration as long as the trimming circuits 1 </ b> A to 1 </ b> C have wiring that can be cut and the characteristics can be adjusted depending on whether or not the wiring is cut. If the internal circuit input terminal 17 and the counter clock input terminal 6 cannot be shared, they may be provided as separate terminals.

  Next, a trimming method will be described with reference to the embodiment in FIG. 1, the flowchart in FIG. 4, and the trimming table example in FIG. Here, how to read the example of the trimming table in FIG. 5 will be described. This example of the trimming table is obtained in advance for the circuit to be adjusted 4 of a plurality of semiconductor circuits, and an oscillation frequency is taken as an example as an analog value to be adjusted. If the specified value of the characteristic is 300 kHz to 350 kHz and the initial characteristic is 300 kHz to 350 kHz, trimming is unnecessary. When the initial characteristic of the circuit 4 to be adjusted before trimming is, for example, 350 kHz to 400 kHz, trimming is performed so that the outputs of the trimming circuits 1C, 1B, and 1A are (O1C, O1B, O1A) = (1, 0, 0). If it performs, it will show that it will become a regulation value 300kHz-350kHz.

  That is, when the initial characteristic of the circuit 4 to be adjusted before trimming is 350 kHz to 400 kHz, the setting value of the counter circuit 3 is set to (O3C, O3B, O3A) = (1, 0, 0), and temporary trimming is performed. For example, it indicates that the specified value is 300 kHz to 350 kHz.

  The occurrence frequency of the trimming table in FIG. 5 indicates the distribution of the oscillation frequency before trimming. If the frequency of occurrence is the trimming pattern that does not cut the wiring of the trimming circuits 1A, 1B, and 1C, and the frequency distribution decreases, the trimming pattern increases the number of cutting of the wirings of the trimming circuits 1A, 1B, and 1C. It is possible to reduce the cut time of the wiring and shorten the test time.

  Finally, the trimming method will be described with reference to the flowchart of FIG. First, the counter circuit 3 is reset (S1), the set values of the counter circuit 3 are set to the initial state (O3C, O3B, O3A) = (0, 0, 0), and the initial characteristics of the circuit 4 to be adjusted are measured ( S2). When the initial characteristic of the circuit to be adjusted 4 is, for example, 410 kHz, measurement is performed halfway until the set value of the counter circuit 3 becomes (O3C, O3B, O3A) = (1, 0, 1) according to the trimming table. Count up without performing (S3-Y, S4-N, S5).

  After that, the characteristics of the circuit to be adjusted 4 are measured again (S6), and it is confirmed that the result is within the specified 300 kHz to 350 kHz (S7-Y, S8). Then, the output values of the trimming circuits 1C, 1B, 1A Is trimmed so that (O1C, O1B, O1A) = (1, 0, 1) (S9).

  In most cases, if provisional trimming is performed according to the trimming table in this way, the characteristics of the circuit to be adjusted 4 should be a specified value of 300 kHz to 350 kHz. In rare cases, the characteristics of the circuit to be adjusted 4 do not become a specified value. There is a case.

  If the characteristic of the circuit to be adjusted 4 does not become a specified value as a result of provisional trimming, the first procedure is to determine whether adjustment is possible unless the set value of the counter circuit 3 is n (n is a natural number) before counting. When the judgment is made (S10) and adjustment is impossible unless the set value of the counter circuit 3 is n counts before (S10-Y), the counter circuit 3 is reset once (S11) and then halfway before n counts. In step S12, the measurement is performed without performing measurement (S12), and the characteristics of the adjusted circuit 4 are measured again (S13).

  For example, as a result of temporary trimming, when the characteristics of the circuit 4 to be adjusted shifts to a lower side from the specified value 300 kHz to 350 kHz, such as 290 kHz, the adjustment is excessive by about 50 kHz. If the current (O3C, O3B, O3A) = (1, 0, 1) is changed to (O3C, O3B, O3A) = (1, 0, 0), the characteristics of the circuit 4 to be adjusted will reach a specified value of 300 kHz to 350 kHz. The counter circuit 3 must be reset once until the set value of the counter circuit 3 becomes (O3C, O3B, O3A) = (1, 0, 0). Then, the measurement is counted up without any intermediate measurement (S12), and the characteristics of the circuit to be adjusted 4 are measured again (S13), and the result becomes the specified 300 kHz to 350 kHz. DOO Make sure (S14-Y), the trimming circuit 1C, 1B, the output value of 1A is (O1C, O1B, O1A) = trimming so that the (1,0,0) (S19).

  If the characteristic of the circuit to be adjusted 4 does not become the specified value as a result of the temporary trimming, as a second procedure, it is possible to determine whether or not the adjustment is possible if the set value of the counter circuit 3 is n counts. If there is (S15-Y), n is counted up (S16), and the characteristics of the circuit 4 to be adjusted are measured again (S17).

  For example, as a result of temporary trimming, when the characteristics of the circuit to be adjusted 4 shift to a higher value with respect to a specified value of 300 kHz to 350 kHz, such as 360 kHz, the adjustment is insufficient by about 50 kHz. Is changed from the current (O3C, O3B, O3A) = (1, 0, 1) to (O3C, O3B, O3A) = (1, 1, 0), the characteristic of the circuit 4 to be adjusted is a specified value of 300 kHz to 350 kHz. Since the adjustment is possible by incrementing by one, the set value of the counter circuit 3 is incremented by one (S16), and the characteristic of the circuit to be adjusted 4 is again measured (S17). After confirming that the specified frequency is 300 kHz to 350 kHz (S18-Y), the output values of the trimming circuits 1C, 1B, 1A are (O1C, O1B, O1A) = (1, , Trimming to be 0) (S9).

  If the temporary trimming is performed twice, the characteristics of the circuit to be adjusted 4 should almost certainly fall within the specified value. If the trimming is still not the specified value, the first adjustment is made until the characteristics of the circuit to be adjusted 4 reach the specified value. Repeat steps 2 and 2 above. By using the trimming method as described above, it is possible to reduce defective samples and perform efficient trimming.

  In the first embodiment of the present invention, as described above, since the number of pads is reduced to prevent an increase in chip size and efficient trimming can be performed, trimming can be performed with almost no increase in cost. By performing temporary trimming before performing trimming, it is possible to measure the same characteristics as when trimming is performed, and to prevent a predetermined characteristic from being obtained after trimming.

<Second embodiment>
FIG. 2 shows a semiconductor circuit according to the second embodiment of the present invention when the number of bits of the trimming pattern is 3 bits. Trimming circuits 1A, 1B, and 1C that have a cuttable wiring and whose characteristics can be adjusted depending on whether or not the wiring is cut, a counter circuit 3, a selector circuit 11 that includes switches 11A, 11B, and 11C, The adjustment circuit 4 is used.

  First, the operation of this circuit will be described. During normal operation, the selector control signal from the mode switching terminal 5 is selected so that the switch 11A selects the output O1A of the trimming circuit 1A, the switch 11B selects the output O1B of the trimming circuit 18, and the switch 11C selects the output O1C of the trimming circuit 1C. , And the circuit to be adjusted 4 is adjusted according to the trimming state of the trimming circuits 1A, 1B, and 1C.

  During the test, the selector control signal is sent from the mode switching terminal 5 so that the switch 11A selects the output O3A of the counter circuit 3, the switch 11B selects the output O3B of the counter circuit 3, and the switch 11C selects the output O3C of the counter circuit 3. When the trimming clock is input from the clock input terminal 6, the counter circuit 3 counts up. That is, the adjusted circuit 4 is adjusted by changing the set values of the outputs O3A, O3B, and O3C of the counter circuit 3.

  During this adjustment, a trimming pattern in which the characteristics of the circuit to be adjusted 4 fall within a specified value is found, and trimming is performed using this trimming pattern. For example, when the characteristics of the circuit to be adjusted 4 enter a specified value when the setting value of the counter circuit 3 is (O3C, O3B, O3A) = (1, 0, 0), the trimming circuits 1C, 1B, 1A Trimming is performed so that the output becomes (O1C, O1B, O1A) = (1, 0, 0).

  Also in this embodiment, as shown in FIG. 3, by using the demultiplexer circuit 7, the internal circuit input terminal 17 and the counter clock input terminal 6 can be combined with one internal circuit input terminal / counter clock input terminal 8. Can be combined.

  The circuit configuration as described above eliminates the need for a trimming data input terminal and a clock input terminal for inputting a trimming clock, so that it is possible to prevent an increase in chip size by reducing terminals, that is, pads. Become.

  The selector circuit 11 and the demultiplexer circuit 7 in the second embodiment of the present invention are not particularly limited as long as they have the same function in addition to the analog switch composed of MOS transistors. The counter circuit 3 is not limited to the D flip-flop as long as it has the same function. The trimming circuits 1 </ b> A to 1 </ b> C are not limited in circuit configuration as long as the trimming circuits 1 </ b> A to 1 </ b> C have wiring that can be cut and the characteristics can be adjusted depending on whether or not the wiring is cut. If the internal circuit input terminal 17 and the counter clock input terminal 6 cannot be shared, they may be provided as separate terminals.

  Next, since the trimming procedure is the same as that of the first embodiment, the description thereof is omitted. By using the trimming method as described above, it is possible to reduce defective samples and perform efficient trimming.

  As described above, the second embodiment of the present invention reduces the number of pads, prevents an increase in chip size, and enables efficient trimming. By performing temporary trimming before performing the trimming, it is possible to measure the same characteristics as when trimming is performed and to prevent a predetermined characteristic from being obtained after trimming.

It is a figure which shows the 1st Example of the semiconductor circuit which enables temporary trimming of this invention. It is a figure which shows the 2nd Example of the semiconductor circuit which enables temporary trimming of this invention. It is a figure which shows the input method of the trimming clock of the 1st, 2nd Example of the semiconductor circuit which enables temporary trimming of this invention. It is a figure which shows the trimming method of the semiconductor circuit which enables the temporary trimming of this invention. It is a figure which shows the example of the trimming table of the semiconductor circuit which enables temporary trimming of this invention. 10 is a schematic diagram of a semiconductor circuit that enables provisional trimming described in Patent Document 1. FIG. FIG. 10 is a schematic diagram of a semiconductor circuit capable of provisional trimming described in Patent Document 2.

Explanation of symbols

  1A, 1B, 1C: trimming circuit, O1A, O1B, O1C: trimming circuit output, 2: selector circuit, 2A, 2B, 2C, 2D, 2E: switch, 3: counter circuit, 3A, 3B, 3C: flip-flop circuit O3A, O3B, O3C: counter circuit output, O3AX, O3BX, O3CX: counter circuit inverted output, 4: adjusted circuit, 5: mode switching terminal, 6: clock input terminal, 7: demultiplexer circuit, 8: internal circuit Input terminal / counter clock input terminal, 9: selector control input terminal, 10: internal circuit, 11: selector circuit, 11A, 11B, 11C: switch, 12: shift register circuit, O12A, O12B, O12C: shift register circuit output , 13: trimming data input terminal, 13A, 13B, 13C: trimming data Data input terminal, 14: a selector control input terminal and a clock input terminal, 15A, 15B, 15C: register circuit, O15A, O15B, O15C: register circuit output, 16: clock input terminal, 17: internal circuit input, 18: semiconductor circuit

Claims (5)

In a semiconductor circuit having n trimming circuits in which wiring is cut / uncut for adjustment of characteristics in a test process after the semiconductor process, and a circuit to be adjusted to which the n trimming circuits are connected ,
A selector circuit and n flip-flop circuits;
By setting the selector circuit to the first mode, the n trimming circuits are connected to the circuit to be adjusted via the n flip-flop circuits,
By setting the selector circuit to the second mode, the n flip-flop circuits constitute an n-bit counter circuit, and the output of the counter circuit is connected to the circuit to be adjusted.
A semiconductor circuit characterized by the above. The semiconductor circuit according to claim 1,
A common input terminal shared by the input terminal of the internal circuit including the circuit to be adjusted and the clock input terminal of the counter circuit;
The common input terminal functions as an input terminal of the internal circuit when the selector circuit is set to the first mode, and a clock input of the counter circuit when the selector circuit is set to the second mode. that acts as a terminal,
A semiconductor circuit characterized by the above. A trimming method using the semiconductor circuit according to claim 1 or 2 ,
Prior to trimming by the n trimming circuits connected to the circuit to be adjusted, provisional trimming is performed on the circuit to be adjusted, and the wiring of the n trimming circuits is cut / not cut according to the result of the temporary trimming In the trimming method to perform
Acquires a trimming table composed of a combination of ²ⁿ types of characteristics of the circuit to be adjusted for a plurality of the semiconductor circuits and ²ⁿ trimming patterns that match each classification characteristic within a specified value range. And
A trimming pattern is selected based on the trimming table according to the current characteristics of the circuit to be adjusted, the trimming pattern is realized by the count value of the n-bit counter circuit, and the counter value of the n-bit counter circuit Is connected to the circuit to be adjusted to perform temporary trimming,
Measuring the provisionally trimmed circuit characteristics to be adjusted;
When the measurement result is within the specified value range, the trimming circuit is cut / uncut so as to have the same trimming pattern as the temporary trimming.
A trimming method characterized by the above. The trimming method according to claim 3,
A measurement result of the characteristics of the circuit to be adjusted that has been provisionally trimmed is a trimming pattern that is out of the range of the specified value and is realized with a first count value that is earlier than the count value of the n-bit counter circuit. When responding,
Counting up to the first count value after resetting the n-bit counter circuit, connecting the output of the count value to the circuit to be adjusted , and performing temporary re-trimming ,
Measure the characteristics of the adjusted circuit that has been re-temporarily trimmed,
When the measurement result is within the specified value range, the trimming circuit is cut / uncut so as to have the same trimming pattern as the re-temporary trimming.
A trimming method characterized by the above. The trimming method according to claim 3 ,
A measurement result of the characteristics of the circuit to be adjusted that has been provisionally trimmed is a trimming pattern that is realized by a second count value that is out of the range of the specified value and exceeds the count value of the n-bit counter circuit. When responding,
The n-bit counter circuit further counts up to the second count value, the output of the count value of the n-bit counter circuit is connected to the circuit to be adjusted, and re-temporary trimming is performed,
Measure the characteristics of the adjusted circuit that has been re-temporarily trimmed,
When the measurement result is within the specified value range, the trimming circuit is cut / uncut so as to have the same trimming pattern as the re-temporary trimming.
A trimming method characterized by the above.

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