Page: Disadvantages of Weighted Resistor DAC
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i) The accuracy and stability of this tyoe DAC depends on the accuracy of the resistors used

ii) This type of DAC requires a wide range of resistors values. If n- then smallest resistor =2 R=2R/s & largest resistor=$2^{\gamma}R=128 R/2$. Thus the largest resistor is 128 times the smallest one . This proportion will be N or se for still higher values of n.

iii) For n=12 if smallest resistance=2.5k/2, thne largest resistance =5.12m$\Omega$. The fabrication of such a large resistance in an ic form is not practically possible.

iv) The finite resistance of the switches disturbs the current particularly in MSB POS where the current settings resistors are small in value.

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