Design and Implementation a 8 bits Pipeline Analog to

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Transcript Design and Implementation a 8 bits Pipeline Analog to

Design and Implementation a 8 bits
Pipeline Analog to Digital Converter in The
Technology 0.6 μm CMOS Process
Eri Prasetyo
Introduction
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ADC convert of pixel analogic value to digital
value in the image CMOS sensor design.
The goal : -ADC can run in the video rate
-It must have small size in the
layout design
We used the Pipeline ADC because it is
simple and it have good conversation rate
and good resolution
Architecture Pipelined ADC
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One bit per stage
Stage 1
Stage 2
V residue
V input
2V
3V
1V
1V
4V
2V
1
0
0
0
Architecture Pipelined ADC
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One bit per stage
Implemented by
Switched Capacitor
Architecture Pipelined ADC
Switched Capacitor
Each stage operates in two phase
-Sampling phase
-Multiplying phase
If D(i) = 1 ,
Vout(i)=2xVin(i)-Di.Vrefp
If D(i) = 0 ,
Vout(i) = 2xVin(i) – Ďi.Vrefn
Architecture Pipelined ADC
Comparator
Consists of three blocks :
•Preamplifier
•Decission circuit
•Output buffer
Architecture Pipelined ADC
Operational Amplifier
-It has a gain 55 dB for bias current 2.5 μA
with Vdd = 5 V and Vss = - 5V
Architecture Pipelined ADC
Result of simulation of Operational Amplifier
The overall performance of the Op-Amp
Architecture Pipelined ADC
Clock Management
We use latch technique
• It is used to hold active condition at multiplying phase until
next stage begin to execute sampling phase
• To keep output voltage of residu before conformity at input
next stage
Architecture Pipelined ADC
Clock Management
The circuit of clock management
•Use counter to count some clock to
active the address decoder from
each stage
•The clock begin working if reset signal
is actived
•The clock finish working if reset signal
inactive
Results
One stage A/D converter layout
Was estimated to occupy about 174 µm X 89 μm
Results
8 bits ADC layout of CHIP photograph
Results
Curve linearity of ADC
The overall specification
And result