ﻃﺮاﺣﯽ و ﺷﺒﯿﻪﺳﺎزي ﯾﮏ ﻣﺒﺪل ﻟﮕﺎرﯾﺘﻢﮔﯿﺮ ﺟﺪﯾﺪ ﺑﺎ اﺳﺘﻔﺎده از ﻧﺴﻞ دوم ﻧﻘﺎﻟﻪ-ﻫﺎي ﺟﺮﯾﺎن

Design and simulation of a new logarithmic converter using the second generation current conveyor

ﭼﮑﯿﺪه: ﯾﮑﯽ از ﻣﺪارﻫﺎي ﭘﺮﮐﺎرﺑﺮد ﻣﺪ ﺟﺮﯾﺎن، ﻣﺪار ﻧﻘﺎﻟﻪ ﺟﺮﯾﺎن اﺳﺖ، ﺑﻄﻮرﯾﮑﻪ ﺑﻌﺪ از آﯾﻨﻪﻫﺎي ﺟﺮﯾﺎن، از ﭘﺮﮐﺎرﺑﺮدﺗﺮﯾﻦ ﻣﺪارﻫﺎ در ﺣﻮزة آﻧﺎﻟﻮگ ﺑﻪ ﺷﻤﺎر ﻣﯽرود. ﻗﺎﺑﻠﯿﺖ ﭘﺮدازش ﻫﻤﺰﻣﺎن وﻟﺘﺎژ و ﺟﺮﯾﺎن، ﭘﻬﻨﺎي ﺑﺎﻧﺪ ﺑﯿﺸﺘﺮ، ﺣﺎﺻﻞﺿﺮب ﺑﻬﺮه در ﭘﻬﻨﺎي ﺑﺎﻧﺪ ﺑﯿﺸﺘﺮ و اﺳﺘﻘﻼل ﺑﻬﺮه از ﭘﻬﻨﺎي ﺑﺎﻧﺪ، از وﯾﮋﮔﯽﻫﺎي ﻗﺎﺑﻞ ﺗﻮﺟﻪ اﯾﻦ ﻣﺪار اﺳﺖ. در اﯾﻦ ﻣﻘﺎﻟﻪ اﻗﺪام ﺑﻪ ﻃﺮاﺣﯽ ﻣﺪار ﻟﮕﺎرﯾﺘﻢﮔﯿﺮ ﺑﺎ ﻧﻘﺎﻟﻪﻫﺎي ﺟﺮﯾﺎن ﺑﺮ اﺳﺎس ﻧﻈﺮﯾﻪ ﻣﺪ ﺟﺮﯾﺎن ﮐﺮدهاﯾﻢ، ﺗﺎ ﺿﻤﻦ ﺑﺮﻃﺮف ﻧﻤﻮدن ﻋﯿﺐﻫﺎي ﻣﺪارﻫﺎي ﻗﺒﻠﯽ، ﻧﻮآوريﻫﺎﯾﯽ در ﻃﺮاﺣﯽ ﻣﺪارﻫﺎي ﻟﮕﺎرﯾﺘﻢﮔﯿﺮ ﻧﯿﺰ داﺷﺘﻪ ﺑﺎﺷﯿﻢ. اراﺋﻪ روﺷﯽ ﺟﺪﯾﺪ ﺑﺮاي ﻃﺮاﺣﯽ ﻣﺪار ﻟﮕﺎرﯾﺘﻢﮔﯿﺮ ﺑﺮاﺳﺎس ﻣﺪ ﺟﺮﯾﺎن، اﺳﺘﻔﺎده از ﻧﻘﺎﻟﻪﻫﺎي ﺟﺮﯾﺎن ﺑﺮاي ﻃﺮاﺣﯽ ﻣﺪار ﻟﮕﺎرﯾﺘﻢﮔﯿﺮ، اﺳﺘﻔﺎده از ﻣﺪارﻫﺎي ﺑﺎ ﺗﻮان و وﻟﺘﺎژ ﮐﻢ، ﻃﺮاﺣﯽ ﻣﺪاري ﺑﺎ ﺧﺮوﺟﯽ ﻣﺴﺘﻘﻞ از دﻣﺎ و در ﻧﺘﯿﺠﻪ ﭘﺎﯾﺪاري ﺑﯿﺸﺘﺮ از ﻧﺘﺎﯾﺞ اراﺋﻪ اﯾﻦ ﻣﻘﺎﻟﻪ اﺳﺖ. در اﯾﻦ روش ﺟﺪﯾﺪ ﺑﺎ ﺗﮑﯿﻪ ﺑﺮ رواﺑﻂ رﯾﺎﺿﯽ ﮐﻪ ﻣﻨﺠﺮ ﺑﻪ ﻟﮕﺎرﯾﺘﻢ ﻃﺒﯿﻌﯽ ورودي ﻣﯽﺷﻮد، ﻃﺮاﺣﯽ ﻣﺪار ﻟﮕﺎرﯾﺘﻢﮔﯿﺮﺟﺪﯾﺪ در ﻓﻨﺎوري µm 0/18 و در ﻣﺪ ﺟﺮﯾﺎن ﺻﻮرت ﭘﺬﯾﺮﻓﺘﻪ، ﺟﺮﯾﺎن ﻣﺼﺮﻓﯽ ﻣﺪار ﺣﺪود µA 5/96 و ﺗﻮان ﻣﺼﺮﻓﯽ µW 2/98، ﺑﻬﺮه dB 69/7، ﺑﺎ ﭘﻬﻨﺎي ﺑﺎﻧﺪ ﺣﺪود kHz 8/5 ﺑﺪﺳﺖ آﻣﺪه اﺳﺖ. ﻋﻤﻠﮑﺮد ﺻﺤﯿﺢ ﻣﺪار ﻃﺮاﺣﯽﺷﺪه ﺑﺎ ﺷﺒﯿﻪﺳﺎزي در ﻧﺮماﻓﺰارﻫﺎي HSPICE و MATLAB ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮارﮔﺮﻓﺘﻪ اﺳﺖ.

One of the most widely used current mode circuits is the current conveyor circuit, so that after current mirrors, they are the most commonly used circuits in the analog field. The ability to process voltage and current at the same time, more bandwidth, gain more bandwidth and gain independence form bandwidth, are notable features of this circuit. In this article, we have designed a logarithm circuit with flow conveyors based on flow theory, so that while eliminating the defects of previous circuits, we can also have innovations in the design of a logarithm circuits. Presenting a new method for designing logarithmic circuit based on current mode, using current conveyors to design logarithmic circuit, using low power and voltage circuits, circuit design with temperature independent output and thus more stability are the results of this article. In this new method, relying on the mathematical relations that lead to the natural input logarithm, a new logarithm circuit is designed. Design of the new logarithm circuit is done in 180 microwatt technology, in the current mode. The current consumption of the circuit is about 5.96 µA, the power consumption is 2.98 µW, the gain is 69.7 dB and bandwidth is about 85 kHz. The correct operation of the designed circuit has been investigated by simulation in HSPICE and MATLAB software.