the description of preferred embodiments according to the present invention is given below , referring to the drawings . fig1 is an exploded perspective view of a chip inductor 24 which has two terminals . base sheets 1 , 2 , 3 and 4 and protective base sheets 8 are rectangular and made of a magnetic material such as ferrite . on the base sheet 1 , a leading electrode 10 and a coil conductor 11 which are made of a conductive paste such as silver and a mixture of silver and palladium by printing or the like . the leading electrode 10 is exposed at a left edge of the base sheet 1 and the coil conductor 11 is connected with the leading electrode 10 . two through holes 20a and 20b which are formed on the base sheet 1 are located at the other end of the conductor 11 . a coil conductor 12 made of the conductive paste is formed on the base sheet 2 . two through holes 21a and 21b are formed at an end of the conductor 12 . at the other end of the conductor 12 , two connecting portions 12a and 12b which have a large connecting area are formed . in the same process as the base sheet 2 , coil conductors 13 and 14 are formed on the base sheets 3 and 4 respectively . two through holes 22a and 22b are formed at an end of the conductor 13 , and connecting portions 13a and 13b are formed at the other end . an end of the conductor 14 is connected with a leading electrode 15 , and connecting parts 14a and 14b are formed at the other end of the conductor 14 . the base sheets 1 - 4 which are prepared in the above process are laminated and then plural protective base sheets 8 are further laminated to the laminate of the sheets 1 - 4 on its upper and lower surfaces . after the lamination , the two through holes 20a and 20b formed at the conductor 11 are overlaid respectively on the connecting portions 12a and 12b formed at the conductor 12 . therefore , the conductors 11 and 12 are connected electrically in series at two connecting points through the through holes 20a and 20b . also , the two through holes 21a and 21b formed at the conductor 12 are overlaid on the connecting portions 13a and 13b formed at the conductor 13 respectively , and the conductors 12 and 13 are connected electrically at the two connecting points through the through holes 21a and 21b . in the same process as explained above , the conductors 13 and 14 are connected electrically through the through holes 22a and 22b . in the above process , a coil is formed between the leading electrodes 10 and 15 . connecting areas of the through holes 20a - 22b and the conductors 11 - 14 are increased compared with the conventional laminated electronic device . therefore even if the base sheets 1 - 4 are not laminated correctly , the chip inductor 24 can work normally as long as one of the two through holes on each sheet is connected electrically with a conductor . for example , as long as one of the through holes 20a and 21b is in contact with the conductor 12 , electrical connection between the conductors 11 and 12 is guaranteed . consequently , the chip inductor 24 which has high reliability of electrical connection between the conductors 11 - 14 can be obtained . as shown in fig2 the chip inductor 24 is covered with the conductive paste of silver , a mixture of silver and palladium , or the like at both sides , and the conductive paste is connected with the leading electrodes 10 and 15 . the conductive paste is baked to form external electrodes ( a ) and ( b ). fig3 is an exploded perspective view of a part of another chip inductor . a leading electrode 27 and a coil conductor 28 which is connected with the leading electrode 27 are formed on a base sheet 25 . at an end of the conductor 28 , three through holes 31a , 31b and 31c are formed staggeringly . a coil conductor 29 is formed on a base sheet 26 . at an end of the conductor 29 , three through holes 32a , 32b and 32c are formed staggeringly , and connecting portions 29a , 29b , 29c which have large connecting area are formed at the other end . when the base sheets 25 and 26 are laminated , the three through holes 31a , 31b and 31c are overlaid on the connecting portions 29a , 29b and 29c respectively . since the through holes 31a , 31b and 31c are positioned staggeringly , higher reliability of electrical connection between the conductors 28 and 29 is ensured . although the present invention has been described in connection with the preferred embodiments above , it is to be noted that various changes and modifications are apparent to a person skilled in the art . such changes and modifications are to be understood as being within the scope of the present invention defined by the appended claims . the present invention is not limited to chip inductors . the present invention can be applied to other electronic devices , for example , an lc filter comprising a coil and a capacitor . the number of through holes which are formed to connect conductors can be more than three , and positioning of these through holes is arbitrary . the base sheets are not limited to the magnetic material such as ferrite , and an insulating material such as dielectric can also be used .