Looking for a 1-bit DAC schematic

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Searching for a 1-bit DAC schematic to use in the design of a swtiched capacitor SIGMA-DELTA ADC. I know that a 1-bit DAC DAC is simply a switch that connects the negative input of the difference amplifier to a positive or a negative reference voltage. I just need a point in the right direction.

Cheers for any help
 

1-bit dac

1-bit DAC is two switches combined together.
Connect inputs of two complementary switches (schematic see in Razzavi Design of Analog CMOS IC, ch.12, p.410-423) to the input of Integrator.
Two outputs of these switches connect to positive and negative reference voltage appropriately.
 

1bit dac

thanks uladz55

Unfortunately that book you are referring to is loaned out at my university's library. I imagine that you could be referring to something similar to a CMOS inverter. This will switch between rails depending on the logic input. I have simulated this circuit in Spice but the only problem is, if i input a logic signal between 0 and 1.8V, the output of the inverter will remain at the positive rail (i chose rails +-0.5V) and will not switch to the negative rail. I can fix this by inputting a logic signal ranging from -1.8 to +1.8, but i rather not since the output of my comparator is either 0 or +1.8V. Any ideas?

-Con
 

dac schematic

here is my schematic
 

1 bit dac schematic

connect to negative or positive Vref means to connect Vref to negative or positive integrator input.
Vref is positive.
 

dac schematics

ur schematic is wrong.

see Razavi book

**broken link removed**
 

1 bit dac circuit

ive downloaded that book, which question am i looking at, is it in chapter 12?

Thanks
 

schematic dac

excuse me, it's lRazavi book's problem solutions.

The book is here
 

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