Question

Data Converters and Timing Circuits (20 marks) (a) For the timing circuit shown below, use a 1000pF capacitor and find the values of RA and RB that result in an oscillation frequency of 100KHz and a duty cycle of 75% Reset 0.693 R,+2R,)C Discharge Outpat Threshold Trigger Ground Duty-Cle2R R,+2R, ar (b) The 4-Bit Weighted-Resistor DAC Converter shown below is to be expanded into an 8-bit device a. What are the required values of the additional resistors to be added? b. Select RF to produce an LSB resolution of 1 for the 8-bit DAC c. What is the output analog voltage if the digital input is Analog value 00000001 00000111 00010000 2 2

Answer 1

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