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ELECTRONICS TROUBLESHOOTING 

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Digital to Analog Converter ( DAC )

 


GIF  animated schematic of a three bit DAC showing normal operation.

 

 

Instructions for DAC Interactive JavaScript Simulation Below( Circuit Schematic Above )

You must click S1, S2, or S4 to initialize program.  Selecting a new Fault requires that you initialize program by selecting No Fault and then closing one of the switches.
Failure to initialize program results initial fault to remain in circuit when a new fault is selected.

 

Panel MeterVout

S4    S2    S1  

DC Voltmeter (General Purpose)


Press above buttons to connect General Purpose DC Voltmeter to DAC.

 

No Fault
Fault 1
Fault 2
Fault 3
Fault 4
Fault 5
Fault 6

 

Specifications

Vout will always equal an integer between 0 - 7 and will not deviate from an integer voltage by more than .02 volts. See animated schematic top of page.

Operational Amplifier Gain (Minimum) = 100000

Operational Amplifier Input Offset  = 1mV (Max.)

Resistor Type  = precision ( + or - 1% )

Maximum closed switch resistance = .5 ohms

Vpos = 15.0 + or - .05 Vdc
Vneg = -15.0 + or -.05 Vdc

 

Answers Below

 

 

 

 

Answers Below

 

 

 

Fault 1

R2 is 8200

 

 

Fault 2

Bad opamp

 

 

Fault 3

S4 closed resistance high

 

 

Fault 4

R5 =82

 

 

 

Fault 5

Vneg = -14.88

 

 

 

Fault 6

R4 = 1031

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