Design and realisation of integrated circuit tester

The input/output logic level currents

The low level input current (I_IL) is the range of current amount needed by an input of an IC to stay at logic “0”; here we also have the minimal low level input current (I_ILMIN) and the maximum low level input current(/_ILMAX).

The High level input current (1_Ш) is the range of current amount needed by an input of an IC to stay at logic “1”; we also have the minimal High level input current (I_IHMIN) and the maximum High level input current (I_IHMAX)

The Low level output current (I_0L) is the range of current amount needed by an input of an IC to stay at logic “0”; here we also have the minimal low level output current (I_0LMIN) and the maximum Low level output current (I_0LMAX).

The High level output current (J_0H)is the range of current amount needed b an input of an IC to stay at logic “1”; we also have the minimal High level output current (I_0HMIN) and the maximum High level output current ( I_0HMAX).

The values (either voltage or current) that do not belong to the input (low or high) and the output (low or high) ranges are in-determined and not recognized by the IC.

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  The Fan-in is the maximum number of outputs that can be accommodated by the input logic circuit. We also have a low level Fan-in and a high level Fan-in.
  
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  The Fan-out is the maximum number of inputs that can be fed by an output of a logic circuit. We also have a low level Fan-out and a high level Fan-out.
  

b) Some dynamic characteristics

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  The frequency f_max and the cyclic ratio
  
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  The propagation or transition time (t_PHLor t_PLH) which corresponds to the time the signal takes to propagate from one logic level to the other.
  
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  The dissipated power (P_tot) which increases in terms of the operating frequency and the help designing the cooling system of the IC.
  
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  The Noise Margin: for an IC robust and insensitive to noise disturbances, it is essential that the “0” and “1” intervals be as large as possible. A measure of the sensitivity of the IC to noise is given by the noise margins N_ML(noise margin low) and N_MH(noise margin high), which quantize the size of the legal “0” and “1” respectively, and set a fixed maximum threshold on the noise value:
  

^mnm = ^Vohmin - ^Vihmin