1 / 11

Digital to Analog Converter

Digital to Analog Converter. By Rushabh Mehta Manthan Sheth. Progress. Current to Voltage converter. V out. 12. 1. I-V conversion. Using a current mirror and load as ground connected PMOS. Possibly the best way to get linear I-V conversion.

kendis
Download Presentation

Digital to Analog Converter

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Digital to Analog Converter By Rushabh Mehta Manthan Sheth

  2. Progress Current to Voltage converter Vout 12

  3. 1. I-V conversion • Using a current mirror and load as ground connected PMOS. • Possibly the best way to get linear I-V conversion. • We evaluated the use of NMOS/PMOS in diode configuration in all possible ways (Doesn’t work) • Always, non-linearity comes when transistor goes from cut-off to saturation. • So, we need to give a constant fixed biasing.

  4. Simulation Result • When all 12 bits are ON => Output voltage = 0.75V • When all 12 bits are OFF => Output voltage= 2.5V • Total Swing = 2.5V to 0.75V

  5. Binary weighted section design • Need unit current sources. • From our calculation, we need a maximum total current of 3.84uA from binary weighted 4 LSB bits => unit current source = 256nA.

  6. Binary weighted section design 4 bit LSB binary encoder

  7. Binary encoder simulation result • Matches perfectly with what was desired. • Swing = 2.5V- 0.75V = 1.75V • Voltage change when all 4 bits ON = • Output voltage = 2.5V – 6.835mV = 2.4931V

  8. Thermometer encoder design MSB 2 Bits 4 Bits Y3 LSB Y2 2 Bits Y1 Y0 Dummy section Y0 = VDD Y1= A1+A0 Y2= A1 Y3= A1.A0

  9. Thermometer encoder design A1 A0 Y1 Y2 Y3

  10. Thermometer encoder simulation result Y3 Y2 Y1 A1 A0

  11. Next • Designing unit current sources for the thermometer coded section. • Level inverter and shifter after I-V conversion. • Designing delay block at the input of binary encoder.

More Related