voltage controlled oscillators
TRANSCRIPT
Voltage-Controlled Oscillators
ECE 453 Final Project
• Lih Feng Cheow (lc259)• Chien Chern Khor (ck245)
• Sining Qi (sq24)
Introduction Voltage-controlled oscillators
Oscillation frequency function of control voltage Implemented 6 VCOs
3 Ring, 3 LC Discuss 5
Metrics for comparison Frequency tuning range Output amplitude Power consumption Linearity of frequency-voltage relationship
Oscillators & Ring Oscillators
deg180)(
1|)(|
...|)(||)(||)(| 03
02
0
jH
jH
VjHVjHVjHVX
• Odd number of gain stages in loop
• At least 3 stages
• Must collectively satisfy Barkhausen conditions above
Differential Ring Oscillator with Variable Resistance
Variable Resistance:Simulation Waveforms
Tuning Range: 130 MHz – 4.41 GHz
Output Amplitude: 0-2.5 VVcontrol Range: 0.58 – 1.75 V
Power Consumption: 16.3 mW
Variable Resistance:Frequency vs. Control Voltage
Frequency vs Control Voltage
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0 0.5 1 1.5 2
Control Voltage (V)
Fre
qu
ency
(G
Hz)
Differential Ring Oscillator with Delay Interpolation
Delay Interpolation: Single Stage
Delay Interpolation:Simulation Waveforms
Tuning Range: 554 MHz – 1.5 GHz
Output Amplitude: 0 – 2.5 VVcontrol Range: 1.25 – 1.75 V Power Consumption: 12.5 mW
Delay Interpolation:Frequency vs. Control Voltage
Frequency vs Control Voltage
0.4
0.6
0.8
1
1.2
1.4
1.6
1 1.2 1.4 1.6 1.8 2
Control Voltage (V)
Fre
qu
ency
(G
Hz)
Negative Resistance
Negative Resistance:Cross Coupled Pair
LC Oscillator with Cross-Coupled NMOS-PMOS
Cross-Coupled NMOS-PMOS: Simulation Waveforms
Vcontrol Range: 0 – 1.3 VTuning Range: 2.24 GHz – 2.6 GHz
Output Amplitude: 0 – 2.5 V
Power Consumption: 3.185 mW
Cross-Coupled NMOS-PMOS: Frequency vs. Control Voltage
Frequency vs Control Voltage
2.2
2.25
2.3
2.35
2.4
2.45
2.5
2.55
2.6
2.65
0 0.2 0.4 0.6 0.8 1 1.2 1.4
Control Voltage (V)
Fre
qu
ency
(H
z)
LC Oscillator with Capacitive Source Degeneration
Capacitive Source Degeneration:Simulation Waveforms
Vcontrol Range: 0 – 2.5 VTuning Range: 2.04 GHz – 2.53 GHz
Output Amplitude: 0 – 2.5 V
Power Consumption: 7.885 mW
Capacitive Source Degeneration Frequency vs. Control Voltage
Frequency vs Control Voltage
2
2.1
2.2
2.3
2.4
2.5
2.6
0 0.5 1 1.5 2 2.5
Control Voltage (V)
Fre
qu
ency
(H
z)
Differential Ring Oscillator with Negative Resistance
pm
p
mpout Rg
R
gRR
1
1//
mg outR
output time constant oscf
2N
m
Rg
1I
Negative Resistance:Schematic
Negative Resistance:Simulation Waveforms
Tuning Range: 1.2 GHz – 1.9 GHz
Output Amplitude: 0 – 2.5 V
Vcontrol Range: 1.3 – 1.5 V
Power Consumption: 7.5 mW
Negative Resistance:Frequency vs. Control Voltage
Frequency vs Control Voltage
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
0.95 1 1.05 1.1 1.15 1.2 1.25
Control Voltage (V)
Fre
qu
en
cy
(G
Hz)
Conclusion
Oscillator Topology Tuning Range(% from center)
Vcontrol Power
Differential Ring Oscillator with Variable Resistor
0.13 – 4.41 GHz(100%)
0.58 – 1.75 V
16.3 mW
Differential Ring Oscillator with Delay Interpolation
0.55 – 1.5 GHz(46%)
1.25 – 1.75 V
12.5 mW
Differential Ring Oscillator with Negative Resistance
1.2 – 1.9 GHz(23%)
1.3 – 1.5 V 7.5 mW
LC Oscillator with NMOS Only Cross-coupled Pair
2.16 – 2.82 GHz(13%)
0 – 2.2 V 11.41 mW
LC Oscillator with NMOS-PMOS Cross-coupled Pair
2.24 – 2.6 GHz(7%)
0 – 1.3 V 3.185 mW
LC Oscillator with Capacitive Source
Degeneration
2.04 – 2.53 GHz(11%)
0 – 2.5 V 7.885 mW
Questions?