Abstract:
The present invention provides a semiconductor memory device that includes: a fuse circuit having multiple fuse elements; and a fuse selection circuit connected to an internal address signal line that receives an address signal externally inputted. The fuse circuit is connected to the fuse selection circuit to receive an output from the fuse selection circuit, is supplied with an externally inputted trigger signal that permits nonvolatile recording of the fuse elements, and, in response to the output and the trigger signal, records the fuse element corresponding to the internal address signal line among the plurality of fuse elements while recording at least one of the plurality of fuse elements other than the fuse element thus recorded.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a semiconductor memory device, and particularly relates to a semiconductor device the failure of which can be redressed based on a test result. 
     2. Description of the Related Art 
     In recent years, a semiconductor memory device has become smaller and grown in capacity, and needs to be subjected to a screening test several times. In the conduct of the screening test, a semiconductor memory device has conventionally been redressed through replacement of a separately-arising defective memory cell with a spare memory cell by fuse cutting (such a redress technique is hereinafter referred to as replacement redress). To carry out such replacement redress several times, however, addition and review of a test circuit and addition of a dedicated signal line for controlling replacement redress are required. Consequently, a chip size becomes larger, which results in a cost increase. What is needed to avoid this is a several-time replacement redress circuit not requiring external control and operations. A conventional semiconductor memory device having a replacement redress circuit is described in Japanese Patent Application Publication No. 2001-23393, for example. 
       FIG. 6  is a block diagram for explaining a configuration of a conventional replacement control circuit  24 . The replacement control circuit  24  includes a complementary address generation circuit  42 , a fuse selection circuit  44 , a replacement address setting circuit  46 , and a decoder deactivation circuit  48 . The complementary address generation circuit  42  receives a fuse selection address signal BSEL provided to select a fuse for storing an address to be replaced, outputs the signal as it is upon a first conduct of replacement, and outputs a complementary address upon a second conduct of replacement. The fuse selection circuit  44  outputs a fuse selection signal BSIG in response to the output from the complementary address generation circuit  42  and an address strobe signal /AS. The replacement address setting circuit  46  outputs a spare selection signal SPSEL in response to an address signal AD externally inputted and the fuse selection signal BSIG. The decoder deactivation circuit  48  deactivates a main address decoder  50  when the spare selection signal SPSEL is activated. When the spare selection signal SPSEL is activated, a spare address decoder  54  decodes the spare selection signal SPSEL and activates a corresponding spare memory cell  56 . 
       FIG. 7  is a circuit diagram showing a configuration of the complementary address generation circuit  42  in  FIG. 6 . The complementary address generation circuit  42  has a circuit  42 # 0  and a circuit  42 # 1 . The circuit  42 # 0  outputs a signal BSEL 0   a  upon receipt of a fuse selection address signal BSEL 0 , and the circuit  42 # 1  outputs a signal BSEL 1   a  upon receipt of a fuse selection address signal BSEL 1 . The circuit  42 # 0  has: an n-channel MOS transistor  68  that is activated upon receipt of an identification. signal SID at a gate thereof when first redundancy replacement is complete and conveys a high voltage BV to a node N 1 ; a resistor  67  that is connected between a power node to which a power supply potential Vcc is provided and the node N 1 ; and an antifuse  66  that is connected between the node N 1  and a ground node. The antifuse is a type of electrical fuse and has a property of becoming conductive between electrodes by being blown. In other words, the antifuse  66  becomes conductive when the high voltage BV is applied to the node N 1 , which causes the node N 1  to have the approximately same potential as the ground node. Hence, the node N 1  is at the H level before a first fuse blowing, but is at the L level after the first fuse blowing. To be more specific, the node N 1  is at the L level when a second fuse blowing is needed as a result of a subsequent test performed after undergoing operational states such as normal read/write operations, other test operations, standby mode or shut-down after leaving replacement redress mode. The circuit  42 # 0  further has: an n-channel MOS transistor  62  being connected between nodes N 2  and N 3  and having a gate connected to the node N 1 ; an inverter  70  that receives and reverses the fuse selection address signal BSEL 0  provided to the node N 2  and outputs the reversed fuse selection address signal BSEL 0  to a node N 4 ; and a p-channel MOS transistor  64  being connected between the nodes N 4  and N 3  and having a gate connected to the node N 1 . 
     The node N 3  outputs the signal BSEL 0   a  being the output of the complementary address generation circuit  42 .  FIG. 7  shows only the fuse selection address signal BSEL 0  in detail; however, in the similar way, the similar circuit  42 # 1  is provided with the fuse selection address signal BSEL 1  and outputs the signal BSEL 1   a  correspondingly. Since the node N 1  is at the H level when the first fuse blowing is to be performed, the n-channel MOS transistor  62  is conductive, and therefore the fuse selection address signal BSEL 0  provided to the node N 2  is conveyed to the node N 3  as it is. On the other hand, since the node N 1  is at the L level when the second fuse blowing is to be performed as described before, the n-channel MOS transistor  62  is nonconductive, and therefore the p-channel MOS transistor  64  connected between the nodes N 4  and N 3  becomes conductive instead. Consequently, the fuse selection address signal BSEL 0  is reversed by the inverter  70 . 
       FIG. 8  is a circuit diagram showing a configuration of the fuse selection circuit  44  in  FIG. 6 . The fuse selection circuit  44  has: a fuse selection decoder  82  that receives and decodes the signals BSEL 0   a  and BSEL 1   a,  which are the output signals of the complementary address generation circuit  42 ; an inverter  84  that receives and reverses the strobe signal /AS of a row or column address; a NOR circuit  86  that outputs a fuse selection signal BSIG 0  upon receipt of an output signal BSIG 0   a  of the fuse selection decoder  82  and the output signal of the inverter  84 ; a NOR circuit  88  that outputs a fuse selection signal BSIG 1  upon receipt of an output signal BSIG 1   a  of the fuse selection decoder  82  and the output signal of the inverter  84 ; a NOR circuit  90  that outputs a fuse selection signal BSIG 2  upon receipt of an output signal BSIG 2   a  of the fuse selection decoder  82  and the output signal of the inverter  84 ; and a NOR circuit  92  that outputs a fuse selection signal BSIG 3  upon receipt of an output signal BSIG 3   a  of the fuse selection decoder  82  and the output signal of the inverter  84 . The fuse selection decoder  82  receives and decodes the signals BSEL 0   a  and BSEL 1   a,  and activates any one of the output signals BSIG 0   a  to BSIG 3   a.  The NOR circuits  86  to  92  activate all the fuse selection signals BSIG 0  to BSIG 3  upon activation of the strobe signal /AS when a row or column address is externally inputted. When the strobe signal /AS is deactivated, the NOR circuits  86  to  92  output, as the fuse selection signals BSIG 0  to BSIG 3 , the signals BSIG 0   a  to BSIG 3   a  decoded in response to the fuse selection address signal BSEL externally provided. 
     As described above, the conventional technology requires a replacement information holding circuit to have a circuit which changes a selected fuse set when replacement redress is necessary. Moreover, the replacement information holding circuit also requires a special control circuit and control procedure for storing, in a nonvolatile manner, a fact that a first replacement redress process has been carried out and completed after completing replacement redress for the required number of defective word and bit lines, and the like, as the first replacement redress. Since circuits to be added in this manner are repeatedly placed for each required replacement redress, a chip size increases and the control procedure becomes more complicated. 
     SUMMARY OF THE INVENTION 
     A semiconductor memory device of an aspect of the present invention is configured including: a fuse circuit having multiple fuse elements; and a fuse selection circuit connected to an internal address signal line that receives an address signal externally inputted. The fuse circuit is connected to the fuse selection circuit to receive an output from the fuse selection circuit, is supplied with an externally inputted trigger signal that permits nonvolatile recording of the fuse elements, and, in response to the output and the trigger signal, records the fuse element corresponding to the internal address signal line among the plurality of fuse elements while recording at least one of the plurality of fuse elements other than the fuse element thus recorded. 
     Such a configuration eliminates the need for a dedicated replacement information holding circuit and a dedicated fuse selection circuit as well as a control procedure using a fuse selection address signal, which have been conventionally necessary. Accordingly, it is possible to securely hold replacement information and implement several-time replacement, with a simple configuration. 
     According to the embodiment, it is made possible to configure a semiconductor memory device capable of accurately performing a replacement process several times with a simple circuit and a simple control procedure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an entire block diagram showing a configuration of a first embodiment. 
         FIG. 2  is a replacement control circuit diagram of the first embodiment. 
         FIG. 3  is a fuse circuit diagram of the first embodiment. 
         FIG. 4  is a replacement address setting circuit diagram of the first embodiment. 
         FIG. 5  is a replacement control circuit diagram showing a configuration of a second embodiment. 
         FIG. 6  is a block diagram of a conventional replacement control circuit. 
         FIG. 7  is a diagram of a conventional complementary address generation circuit. 
         FIG. 8  is a diagram of a conventional fuse selection circuit. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Specific examples of embodiments will hereinafter be described with reference to the drawings. All of the following descriptions are one of examples, and do not limit the present invention of the application. Those skilled in the art can understand and carry out the present invention in an aspect with appropriate changes and addition within the scope of the present invention of the application. 
       FIG. 1  is a block diagram showing a configuration of a first embodiment. A semiconductor memory device of the present invention includes a replacement control circuit  10  which further includes a fuse selection circuit  20  and a fuse circuit  21 , a replacement address setting circuit  400 , a decoder deactivation circuit  410 , a main address decoder  420 , a main memory cell  12 , and a spare memory cell  11 . Address signals A 0  and A 1  inputted externally are connected to the fuse selection circuit  20  of the replacement control circuit  10 , the replacement address setting circuit  400 , and the main address decoder  420 . A cut trigger signal  204  inputted externally is connected to the fuse circuit  21 . The fuse selection circuit  20  and the fuse circuit  21  of the replacement control circuit  10  are connected to each other with cut selection signals  250   a  to  250   c,    251   a  to  251   c,    252   a  to  252   c,  and  253   a  to  253   c.  Enable fuse signals  230   c  to  233   c  are connected to the fuse selection circuit  20 , and output signals  230   a  to  230   c,    231   a  to  231   c,    232   a  to  232   c,  and  233   a  to  233   c  are connected to the replacement address setting circuit  400 . Output signals RWL 0  to  3  of the replacement address setting circuit  400  are connected to the decoder deactivation circuit  410  and the spare memory cell  11 . An output signal  411  of the decoder deactivation circuit  410  is connected to the main address decoder  420 . Output signals WL 0  to  3  of the main address decoder  420  are connected to the main memory cell  12 . 
       FIG. 2  is a circuit diagram of the fuse selection circuit  20  and a block diagram of the fuse circuit  21 , both of which configure the replacement control circuit  10  in  FIG. 1 .  FIG. 2  is configured of fuse selection circuits  250 ,  251 ,  252 , and  253 , and circuit blocks  220 ,  221 ,  222  and  223 . The circuit blocks  220  to  223  are configured of fuse circuits  220   a  to  220   c,    221   a  to  221   c,    222   a  to  222   c,  and  223   a  to  223   c,  respectively. The fuse selection circuit  250  is configured of two-input AND circuits  240   a  and  240   b  and an inverter circuit  260 . The fuse selection circuit  251  is configured of two-input AND circuits  241   a  and  241   b,  a two-input NOR circuit  261 , and a two-input OR circuit  271 . The fuse selection circuit  252  is configured of two-input AND circuits  242   a  and  242   b,  a two-input NOR circuit  262 , and a two-input OR circuit  272 . The fuse selection circuit  253  is configured of two-input AND circuits  243   a  and  243   b,  and a two-input NOR circuit  263 . The address signals A 0  and A 1  externally inputted to the fuse selection circuit  250  and the circuit block  220  are connected to the two-input AND circuits  240   a  and  240   b,  respectively. The cut trigger signal  204  is connected to the fuse circuits  220   a  to  220   c.  The outputs  250   a  and  250   b  of the two-input AND circuits  240   a  and  240   b  are connected to the fuse circuits  220   a  and  220   b,  respectively. The enable fuse signal  230   c  is connected to the inverter  260 , and the output  250   c  is connected to the two-input AND circuits  240   a  and  240   b,  the fuse circuit  220   c,  and the two-input NOR circuit  261  and the two-input OR circuit  271  of the fuse selection circuit  251 . 
     The address signals A 0  and A 1  inputted to the fuse selection circuit  251  and the circuit block  221  are connected to the two-input AND circuits  241   a  and  241   b,  respectively. The cut trigger signal  204  is connected to the fuse circuits  221   a  to  221   c.  The outputs  251   a  and  251   b  of the two-input AND circuits  241   a  and  241   b  are connected to the fuse circuits  221   a  and  221   b,  respectively. The enable fuse signal  231   c  is connected to the two-input NOR signal  261 . The output  251   c  is connected to the two-input AND circuits  241   a  and  241   b,  the fuse circuit  221   c,  and the two-input OR circuit  271 . An output  281  of the two-input OR circuit  271  is connected to the two-input NOR circuit  262  and the two-input OR circuit  272  of the fuse selection circuit  252 . 
     The address signals A 0  and A 1  inputted to the fuse selection circuit  252  and the circuit block  222  are connected to the two-input AND circuits  242   a  and  242   b,  respectively. The cut trigger signal  204  is connected to the fuse circuits  222   a  to  222   c.  The outputs  252   a  and  252   b  of the two-input AND circuits  242   a  and  242   b  are connected to the fuse circuits  222   a  and  222   b,  respectively. The enable fuse signal  232   c  is connected to the two-input NOR circuit  262 . The output  252   c  is connected to the two-input AND circuits  242   a  and  242   b,  the fuse circuit  222   c,  and the two-input OR circuit  272 . An output  282  of the two-input OR circuit  272  is connected to the two-input NOR circuit  263  of the fuse selection circuit  253 . 
     The address signals A 0  and A 1  inputted to the fuse selection circuit  253  and the circuit block  223  are connected to the two-input AND circuits  243   a  and  243   b,  respectively. The cut trigger signal  204  is connected to the fuse circuits  223   a  to  223   c.  The outputs  253   a  and  253   b  of the two-input AND circuits  243   a  and  243   b  are connected to the fuse circuits  223   a  and  223   b,  respectively. The enable fuse signal  233   c  is inputted to the two-input NOR circuit  263 , and an output  253   c  is connected to the two-input AND circuits  243   a  and  243   b  and the fuse circuit  223   c.    
     Next, descriptions will be given of a configuration of the block  220  holding a first replacement address. 
     The block  220  is configured of the three fuse circuits  220   a,    220   b  and  220   c.  The fuse circuit  220   a  is connected with the A 0  cut selection signal  250   a  from the block  250  and the cut trigger signal  204 , and outputs the A 0  address fuse signal  230   a.  The fuse circuit  220   b  is connected with the A 1  cut selection signal  250   b  from the block  250  and the cut trigger signal  204 , and outputs the A 1  address fuse signal  230   b.  The fuse circuit  220   c  is connected with the fuse use ban signal  250   c  from the block  250  and the cut trigger signal  204 , and outputs the enable fuse signal  230   c.  A configuration of the block  221  holding a second replacement address is the same as the first one. The block  221  has the fuse circuits  221   a,    221   b  and  221   c,  and outputs the A 0  address fuse signal  231   a,  the A 1  address fuse signal  231   b,  and the enable fuse signal  231   c,  respectively. A configuration of the block  222  holding a third replacement address is the same as the first one. The block  222  has the fuse circuits  222   a,    222   b,  and  222   c,  and outputs the A 0  address fuse signal  232   a,  the A 1  address fuse signal  232   b,  and the enable fuse signal  232   c,  respectively. A configuration of the block  223  holding a fourth replacement address is the same as the first one. The block  223  has the fuse circuits  223   a,    223   b,  and  223   c,  and outputs the A 0  address fuse signal  233   a,  the A 1  address fuse signal  233   b,  and the enable fuse signal  233   c,  respectively. 
       FIG. 3  is a detailed circuit diagram of the fuse circuit block  21 . 
     The block  21  is configured of the blocks  220  to  223 . The block  220  is configured of the fuse circuits  220   a  to  220   c  which are configured of two-input AND circuits  300   a  to  300   c,  n-channel transistors  320   a  to  320   c,  electric fuses  310   a  to  310   c,  high resistors  330   a  to  330   c,  and inverters  350   a  to  350   c,  respectively. In the fuse circuit  220   a,  the cut selection signal  250   a  and the cut trigger signal  204  are connected to the two-input AND circuit  300   a,  and the output is connected to a gate of the n-channel transistor  320   a.  A source of the n-channel transistor  320   a  is connected to GND, and a drain node  340   a  is connected to the electric fuse  310   a,  the high resistor  330   a,  and the inverter  350   a.  The electric fuse  310   a  is connected to the node  340   a  and the power supply VCC. The high resistor  330   a  is connected to the node  340   a  and GND. Internal connection relations in the fuse circuits  220   b  and  220   c  are the same as that of the fuse circuit  220   a.  In addition, the internal configurations and the connection relations of the blocks  221  to  223  are the same as the block  220 . 
       FIG. 4  is a detailed circuit diagram of the replacement address setting circuit  400 , a circuit diagram of the decoder deactivation circuit  410 , and a block diagram of the main address decoder  420 . 
     The replacement address setting circuit  400  is configured of a three-input AND circuit  460 , two-input XNOR circuits  450   a  and  450   b,  a three-input AND circuit  461 , two-input XNOR circuits  451   a  and  451   b,  a three-input AND circuit  462 , two-input XNOR circuits  452   a  and  452   b,  a three-input AND circuit  463 , and two-input XNOR circuits  453   a  and  453   b.    
     The address input A 0  and the address fuse signals  230   a,    231   a,    232   a,  and  233   a  are connected to the two-input XNOR circuits  450   a,    451   a,    452   a,  and  453   a,  respectively. The address input A 1  and the address fuse signals  230   b,    231   b,    232   b,  and  233   b  are connected to the two-input XNOR circuits  450   b,    451   b,    452   b,  and  453   b,  respectively. The outputs of the two-input XNOR circuits  450   a  and  450   b  and the enable fuse signal  230   c  are connected to the three-input AND circuit  460 . The outputs of the two-input XNOR circuits  451   a  and  451   b  and the enable fuse signal  231   c  are connected to the three-input AND circuit  461 . The outputs of the two-input XNOR circuits  452   a  and  452   b  and the enable fuse signal  232   c  are connected to the three-input AND circuit  462 . The outputs of the two-input XNOR circuits  453   a  and  453   b  and the enable fuse signal  233   c  are connected to the three-input AND circuit  463 . The outputs RWL 0  to  3  of the three-input AND circuits  460  to  463  are connected to a four-input NOR circuit  412  of the decoder deactivation circuit  410 . The main address decoder  420  is connected to the address inputs A 0  and A 1 , and the output  411  of the four-input NOR circuit  412  from the decoder deactivation circuit  410 . 
     Descriptions will be given of several-time replacement operations of the present invention with reference to  FIGS. 1 ,  2 ,  3  and  4 . 
     The block  250  of the fuse selection circuit  20  receives the enable fuse signal  230   c  and the address signals A 0  and A 1  externally inputted and outputs the cut selection signals  250   a  to  250   c  to the fuse circuit  21 . The block  220  of the fuse circuit  21  takes the cut selection signals  250   a  to  250   c  and the cut trigger signal  204  as inputs and cuts a fuse selected by the cut selection signals  250   a  to  250   c  based on a one-shot high level input of the cut trigger signal  204 . The output signals  230   a  to  230   c  of the block  220  are further connected to the replacement address setting circuit  400 , too. As the above-mentioned blocks  250  and  220 , the blocks  251  to  253  output the cut selection signals  251   a  to  251   c,    252   a  to  252   c,  and  253   a  to  253   c,  and the blocks  221  to  223  output the output signals  231   a  to  231   c,    232   a  to  232   c,  and  233   a  to  233   c.  The output signals  230   a  to  230   c,    231   a  to  231   c,    232   a  to  232   c,    233   a  to  233   c  are compared with the address signals A 0  and A 1 . If they agree with each other, one of the replacement address signals RWL 0  to  3  is outputted at the high level, and the other signals is outputted at the low level. These signals are connected to the spare memory cell  11 . Furthermore, the replacement address signals RWL 0  to  3  are also inputted to the decoder deactivation circuit  410 . If anyone of the replacement address signals RWL 0  to  3  is at the high level, the output signal  411  of the decoder deactivation circuit  410  is inputted as a non-selection signal to the main address decoder  420 . Thereby, all the main address decoding signals WL 0  to  3  are outputted at the low level, and the main memory cell  12  is put in a non-select state. If the replacement address signals RWL 0  to  3  are all at the low level, the output signal  411  of the decoder deactivation circuit  410  is outputted at the high level. The main address decoder  420  receives the address signals A 0  and A 1  and outputs any one of the main address decoding signals WL 0  to  3  at the high level. 
     Firstly, descriptions will be given of operations performed when a memory cell selected by the address signal (A 0 , A 1 )=(0, 1) fails in a first test. In this case, the semiconductor memory device in the embodiment inputs the address signal (A 0 , A 1 )=(0, 1) as the operations of the replacement redress mode state in the fuse selection circuit  20  in  FIG. 2 . Moreover, the cut trigger signal  204  is set to an initial value of the low level. The fuse circuit  220  holding a first replacement address is not cut in an initial state; therefore, the enable fuse signal  230   c  is outputted at the low level, and the fuse use ban signal  250   c  is outputted at the high level (cut permission). The two-input AND circuit  300   c  of the fuse circuit  220  and the two-input AND circuits  240   a  and  240   b  of the fuse selection circuit  250  are put in a select state. Since (A 0 , A 1 )=(0, 1) is inputted, the output signal  250   a  is at the low level, the output signal  250   b  is at the high level. Accordingly, the two-input AND circuits  300   a  and  300   b  are put in the non-select state and the select state, respectively. Then, when the cut trigger signal  204 , being a permission signal to permit a fuse cut, transits to the high level at one shot, the n-channel transistors  320   b  and  320   c  selected by the two-input AND circuits  300   b  and  300   c  are switched on, responding to the transition in common. Accordingly, current flows through the electric fuses  310   b  and  310   c,  and the fuses are cut. As a result, the potential of the nodes  340   b  and  340   c  is at the low level afterwards. 
     Cutting a fuse for redressing a defective cell for the address signal (A 0 , A 1 )=(0, 1) has been shown as the first replacement redress process in this example. If two or more address signals need to be redressed, the same fuse cutting may be repeated, and each fuse cutting may be set as the first replacement redress process. Furthermore, the fuse element  310   c  that execute a program by being electrically cut, and the like are used in this example. Alternatively, it is also possible to use an antifuse element that is insulated in the initial state and becomes electrically conductive by feeding a large current. In this case, contrary to the example described here, the potential of the node  340   c  and the like of when replaced and when not replaced is at the low level at the beginning and is at the high level upon execution of the program. Therefore, the same circuit operations can be performed if the logic levels of the signal  230   c  and the like are set to be the same as the above example by appropriately making changes such as increasing the numbers of stages of the inverter  350   c  and the like. 
     The semiconductor memory device of the embodiment can perform normal read/write operations after completing the first fuse cutting in this manner and leaving the replacement redress mode, it is possible to perform normal reading/writing in response to external access to a replaced defective address by selecting a specific spare cell among spare cells after replacement. Moreover, after the first test or the first replacement redress, the semiconductor memory device can normally operate during any of operational states including other test operations, standby mode and shut-down. In this case, the fuse  310   c  and the like store replacement states in a nonvolatile manner; therefore, the memory of the replacement states will not be lost by the operational states such as the shut-down of the semiconductor device. 
     Next, descriptions will be given of operations performed when a memory cell selected by the address signal (A 0 , A 1 )=(0, 0) and (1, 0) fails in a second test. Since the electric fuse  310   c  is cut in the first test and the node  340   c  is at the low level due to the high resistor  330   c  with a resistance value of several KΩ to several MΩ, the enable fuse signal  230   c  of the fuse circuit  220   c  is outputted at the high level through the inverter  350   c.  Moreover, the fuse use ban signal  250   c  is outputted at the low level (cut ban). Consequently, the A 0  and A 1  cut selection signals  250   a  and  250   b  are also at the low level, and the fuse circuit  220  is put in the non-select state. Thereby, redundant fuse cutting is avoided. Since the electric fuse  311   c  is not cut, the enable fuse signal  231   c  of the second fuse circuit  221  is outputted at the high level and inputted to the two-input NOR circuit  261  of the fuse selection circuit  251  together with the fuse use ban signal  250   c.  The fuse use ban signal  251   c  is outputted at the high level (cut permission). The two-input AND circuits  241   a  and  241   b  are put in the select state. However, since the address signal (A 0 , A 1 ) (0, 0), the outputs  251   a  and  251   b  are at the low level, and the fuse use ban signal  251   c  is inputted at the high level to the fuse circuits  221   a,    221   b,  and  221   c.  If the cut trigger signal  204  transits to the high level at one shot, only the electric fuse for the fuse circuit  221   c  is selected and cut. Then, the fuse circuit outputs  231   a  and  231   b  are outputted at the low level, and the enable fuse signal  231   c  is outputted at the high level. Since the enable fuse signal  231   c  is at the high level, the fuse use ban signal  251   c  is at the low level. Then, the two-input NOR circuit  261  is inputted, together with the fuse use ban signal  250   c  (low level), to the two-input OR circuit  271 . The output  281  is at the low level. Next, when the address signal (A 0 , A 1 )=(1, 0) is inputted, the two-input AND circuits  242   a  and  242   b  in the third fuse circuit  252  are selected. Then, the A 0  cut selection signal  252   a  is at the high level, and the A 1  cut selection signal  252   b  is at the low level. In the fuse circuits  222   a,    222   b  and  222   c,  when the cut trigger signal  204  is at the high level at one shot, electric fuses for  222   a  and  222   c  are selected. Then, the outputs  232   a  and  232   b  and the enable fuse signal  232   c  are outputted at the high level, the low level, and the high level, respectively. 
     At this point, when the A 0  address fuse signal  230   a  and the A 1  address fuse signal  230   b  agree with the external address signals A 0  and A 1  and the enable fuse signal  230   c  is at the high level in the replacement address setting circuit  400  in  FIG. 4 , the three-input AND circuit  460  is outputted at the high level, and sets RWL 0  as a replacement address. Additionally, RWL 0  is inputted to a four-input NOR circuit of the decoder deactivation circuit  410 , and the output  411  is outputted at the low level. The output  411  is inputted to the main address decoder  420  to set the decoding signals WL 0  to  3  of the external address signals A 0  and A 1  to non-select (low level). With respect to the replacement address setting circuit  400 , the A 0  address fuse signals  231   a,    232   a  and  233   a,  and the A 1  address fuse signals  231   b,    232   b  and  233   b,  which hold the second to fourth replacement address, respectively, and the enable fuse signals  231   c,    232   c  and  233   c,  are inputted similarly to the ones from the first block  220 . When the respective signals agree with the external addresses A 0  and A 1 , and the enable fuse signals  231   c,    232   c,  and  233   c  are at the high level respectively, the replacement address signals RWL 1  to  3  are set by the three-input AND circuits  461 ,  462  and  463 . The output signal  411  of the decoder deactivation circuit  410  is at the low level, and the output signals WL 0  to  3  of the main address decoder  420  are set to the non-select low level. The representation of (0, 1) in the above descriptions indicates (low level, high level). 
     As described above, in the illustrated several-time replacement control circuit, the cut/non-cut state output of a fuse circuit used for replacement redress is used as a fuse use ban signal. A fuse circuit used for replacement redress has a cut-state memory element that is cut by commonly responding to the cut trigger signal being a cut permission signal for cutting a fuse in relation to an address to be replaced, and generates a cut/non-cut state output. In addition, it is configured so that an OR of the fuse use ban signal and the fuse use ban signal of the selected fuse circuit, of a previous stage, is passed to a following stage. Accordingly, without any special dedicated fuse circuit, a fuse circuit in the following stage is selected only when all the fuse circuits in the previous stages are banned for use (have already been used). Consequently, a dedicated replacement information holding circuit, fuse selection circuit, and fuse selection address signal, which have all been necessary in the conventional example, are no longer necessary. 
     A second embodiment has a configuration in which an SR latch circuit to latch address signals A 0  and A 1 , and an enable fuse signal is added to the configuration in  FIG. 2  of the first embodiment. The other different point is to use, as a latch trigger signal, a one-shot judgment signal that uses a memory test pass/fail judgment result by BIST.  FIG. 5  is a replacement control circuit diagram showing the second embodiment of the present invention. 
     The replacement control circuit of the second embodiment has the fuse selection circuit  20  and the fuse circuit  21  configured of fuse selection circuits  260 ,  261 ,  262 , and  263 , and circuit blocks  220 ,  221 ,  222 , and  223 , respectively. The circuit blocks  220  to  223  are configured of fuse circuits  220   a  to  220   c,    221   a  to  221   c,  and  223   a  to  223   c,  respectively. The fuse selection circuit  260  is configured of two-input AND circuits  270   a,    270   b,  and  500 , a two-input NOR circuit  540 , a two-input OR circuit  270   c,  and SR latch circuits  520   a  to  520   c.  The fuse selection circuit  261  is configured of two-input AND circuits  271   a,    271   b  and  501 , a three-input NOR circuit  541 , two-input OR circuits  271   c  and  544 , and SR latch circuits  521   a  to  521   c.  The fuse selection circuit  262  is configured of two-input AND circuits  272   a,    272   b,  and  502 , a three-input NOR circuit  542 , two-input OR circuits  272   c  and  545 , and SR latch circuits  522   a  to  522   c.  The fuse selection circuit  263  is configured of two-input AND circuits  273   a,    273   b  and  503 , a three-input NOR circuit  543 , a two-input OR circuit  273   c,  and SR latch circuits  523   a  to  523   c.    
     The address signal A 0  externally inputted is connected to the two-input AND circuits  270   a,    271   a,    272   a  and  273   a.  The address signal A 1  is connected to the two-input AND circuits  270   b,    271   b,    272   b,  and  273   b.  A cut trigger signal  204  is connected to the fuse circuits  220   a  to  220   c,    221   a  to  221   c,    222   a  to  222   c,  and  223   a  to  223   c.  A reset signal  560  is connected to a reset side of the SR latch circuits  520   a  to  520   c,    521   a  to  521   c,    522   a  to  522   c,  and  523   a  to  523   c,  and a one-shot judgment signal  570  is connected to the two-input AND circuits  500 ,  501 ,  502  and  503 . 
     The fuse selection circuit  260  and the fuse circuit  220  hold a first replacement address; The fuse selection circuit  261  and the fuse circuit  221  hold a second replacement address; the fuse selection circuit  262  and the fuse circuit  222  hold a third replacement address; and the fuse selection circuit  263  and the fuse circuit  223  hold a fourth replacement address. In the fuse selection circuit  260  and the circuit block  220 , outputs  540   a  to  540   c  of the two-input AND circuits  270   a  and  270   b  and the two-input OR circuit  270   c  are inputted to set sides of the SR latch circuits  520   a  to  520   c,  and outputs  530   a  to  530   c  are connected to the fuse circuits  220   a  to  220   c,  respectively. The SR latch circuit  520   c  is connected to the two-input NOR circuit  540  and the two-input OR circuit  270   c.  An output enable fuse signal  230   c  of the fuse circuit  220   c,  together with the output  530   c  of the SR latch circuit  520   c,  is connected to the two-input NOR circuit  540 . An output  550  is connected to the two-input AND circuit  500 , and the three-input NOR circuit  541  and the two-input OR circuit  544  of the fuse selection circuit  261 . An output  510  of the two-input AND circuit  500  is connected to the two-input AND circuits  270   a  and  270   b  and the two-input OR circuit  270   c.  In the fuse selection circuit  261  and the fuse block  221 , outputs  541   a  to  541   c  of the two-input AND circuits  271   a  and  271   b  and the two-input OR circuit  271   c  are inputted to-set sides of the SR latch circuits  521   a  to  521   c,  and outputs  531   a  to  531   c  are connected to the fuse circuits  221   a  to  221   c,  respectively. The SR latch circuit  521   c  is connected to the three-input NOR circuit  541  and the two-input OR circuit  271   c.  An output enable fuse signal  231   c  of the fuse circuit  221   c,  together with the output  531   c  of the SR latch circuit  521   c,  is connected to the three-input NOR circuit  541 . An output  551  is connected to the two-input AND circuit  501  and the two-input OR circuit  544 , and an output  546  of the two-input OR circuit  544  is connected to the three-input NOR circuit  542  and the two-input OR circuit  545  of the fuse selection circuit  262 . An output  511  of the two-input AND circuit  501  is connected to the two-input AND circuits  271   a  and  271   b,  and the two-input OR circuit  271   c.  In the fuse selection circuit  262  and the circuit block  222 , outputs  542   a  to  542   c  of the two-input AND circuits  272   a  and  272   b,  and the two-input OR circuit  272   c  are connected to set sides of the SR latch circuits  522   a  to  522   c,  and outputs  532   a  to  532   c  are connected to the fuse circuits  222   a  to  222   c,  respectively. The SR latch  522   c  is connected to the three-input NOR circuit  542  and the two-input OR circuit  272   c.  An output enable fuse signal  232   c  of the fuse circuit  222   c,  together with the output  532   c  of the SR latch circuit  522   c,  is connected to the three-input NOR circuit  542 . An output  552  is connected to the two-input AND circuit  502  and the two-input OR circuit  545 , and output  547  of the two-input OR circuit  545  is connected to the three-input NOR circuit  543  of the fuse selection circuit  263 . An output  512  of the two-input AND circuit  502  is connected to the two-input AND circuits  272   a  and  272   b,  and the two-input OR circuit  272   c.    
     In the fuse selection circuit  263  and the circuit block  223 , outputs  543   a  to  543   c  of the two-input AND circuits  273   a  and  273   b,  and the two-input OR circuit  273   c  are inputted to set sides of the SR latch circuits  523   a  to  523   c,  and their outputs  533   a  to  533   c  are connected to the fuse circuits  223   a  to  223   c,  respectively. The SR latch circuit  523   c  is connected to the three-input NOR circuit  543  and the two-input OR circuit  273   c.  An output enable fuse signal  233   c  of the fuse circuit  223   c,  together with the output  533   c  of the SR latch circuit  523   c,  is connected to the three-input NOR circuit  543 . An output  553  is connected to the two-input AND circuit  503 . An output  513  of the two-input AND circuit  503  is connected to the two-input AND circuits  273   a  and  273   b,  and the two-input OR circuit  273   c.  The fuse circuits  220  to  223  have the same configurations as the first embodiment. 
     Descriptions will be given of several-time replacement operations of the second embodiment with reference to  FIG. 5 . 
     Firstly, descriptions will be given of operations performed when a memory cell selected by an address signal (A 0 , A 1 )=(0, 1) fails in a first test. As an initial operation, a one-shot high level is outputted from the reset signal  560  to reset the SR latch circuits  520   a  to  520   c,    521   a  to  521   c,    522   a  to  522   c,  and  523   a  to  523   c,  and to set the output signals  530   a  to  530   c,    531   a  to  531   c,    532   a  to  532   c,  and  533   a  to  533   c  to the low level. In addition, an electric fuse of the fuse circuit is in a non-cut state, the enable fuse signals  230   c  to  233   c  are at the low level, and the output  550  of the two-input NOR circuit  540  of the fuse judgment circuit  260  is at the high level. When a memory cell selected by the address signal (A 0 , A 1 )=(0, 1) is at the high level, the one-shot judgment signal  570  is at the one-shot high level, the output  510  of the two-input AND circuit  500  is at the high level, the output signal  540   a  of the two-input AND circuits  270   a  and  270   b  for the address signals A 0  and A 1  are the low level, the output signal  540   b  is at the high level, and the output signal  540   c  of the two-input OR circuit  270   c  is at the high level. The output signal  530   a  of the SR latch circuits  520   a,    520   b  and  520   c  are set at the low level, the output signal  530   b  at the high level, and the output signal  530   c  at the high level. The two-input AND circuit  300   a  is put in a non-select state,  300   b  in a select state, and  300   c  in the select state. When the cut trigger signal  204  transits to the high level at one shot, n-channel transistors  320   b  and  320   c  selected by the two-input AND circuits  300   b  and  300   c  are switched on to feed current through electric fuses  310   b  and  310   c,  and the fuses are cut. 
     Next, descriptions will be given of operations performed when a main memory cell selected by the address signals (A 0 , A 1 )=(0, 0) and (1, 0) is defective in a second test. Since an electric fuse  310   c  is cut in the first test and a node  340   c  is at the low level due to a high resistor  330   c,  the enable fuse signal  230   c  of the fuse circuit  220   c  is outputted at the high level through an inverter  350   c.  The fuse use ban signal  550  is at the low level (cut ban), and the output  510  is at the low level (cut ban). The A 0  and A 1  cut selection signals  540   a  and  540   b  are also at the low level due to the output  510 , and the fuse circuit  220  is put in the non-select state. Accordingly, the redundant fuse cutting is avoided. The enable fuse signal  231   c  of the second fuse circuit  221  is outputted at the low level since the electric fuse  310   b  is not cut, and is inputted to the three-input NOR circuit  541  of the fuse selection circuit  261  together with the output signal  531   c  (low level) and the fuse use ban signal  550  (low level). The output  551  is outputted at the high level (cut permission). When the one-shot judgment signal  570  is outputted at a one-shot high level, the output  511  of the two-input AND circuit  501  is at the high level; the output signals  541   a  and  541   b  of the two-input AND circuits  271   a  and  271   b  for the address signals A 0  and A 1  is at the low level; and the output signal  541   c  of the two-input OR circuit  271   c  is at the high level. Consequently, the output signal  531   a  of the SR latch circuits  521   a,    521   b  and  521   c  is set at the low level, the output signal  531   b  at the low level, and the output signal  531   c  at the high level.  221   a  of the fuse circuit  221  is put in the non-select state,  221   b  in the non-select state, and  221   c  in the select state. A fuse selected by the cut trigger signal  204  is cut here in  FIG. 2  of the first embodiment. In the second embodiment, on the other hand, the cut trigger signal  204  need not be cut until the end of the second test since the  531   a,    531   b  and  531   c  signals are latched by the SR latch circuits. Next, when a memory cell selected by the address signal (A 0 , A 1 )=(1, 0) is at the high level, the signal  546 , the enable fuse signal  232   c,  and the fuse use ban signal  532   c  are inputted all at the low level to the three-input NOR circuit  542  in the fuse circuit  262 . Thereby, an output  552  is at the high level. When the one-shot judgment signal  570  is outputted at a one-shot high level, the output  512  of the two-input AND circuit  502  is at the high level, the output signal  542   a  of the two-input AND circuits  272   a  and  272   b  for the address signals A 0  and A 1  is at the high level, the output signal  542   b  is at the low level, and the output signal  542   c  of the two-input OR circuit  272   c  is at the high level. Then, the output signal  532   a  of the SR latch circuits  522   a,    522   b  and  522   c  is set at the high level, the output signal  532   b  at the low level, and the output signal  532   c  at the high level. 
     When the input of the cut trigger signal  204  is changed at the one-shot high level after the end of the second test, fuses selected by the input signals  531   c,    532   a  and  532   c  are simultaneously cut in the fuse selection circuits  221  and  222 . 
     As described above, a circuit that latches the address A 0  and A 1  signals and the enable fuse signal is provided in the second embodiment. Thereby, cutting data can be held for each fuse set even if fuse cutting is not performed, and fuse cutting operations are performed once at the end of the test. The conventional technique has required a replacement information holding circuit and a fuse selection circuit, both of which are dedicated for changing the order of fuse selection, and an address signal for fuse selection. However, in this embodiment, selection of the next fuse is made based on the replacement fuse cutting information of a replacement control circuit to be selected. Accordingly, there is no longer a need to have a dedicated replacement information holding circuit and a dedicated fuse selection circuit, and an address signal (BSEL) for fuse selection. Thereby, a small chip size can be accomplished. When comparing the same configuration examples, for example, the necessary number of fuses 4×4 sets+2=18 pieces is reduced to the number of fuses 3×4 sets=12 pieces, according to the embodiment. As a result, the number of fuses decreases to 12/18, which results in a size reduction effect of 67%.