1

Programmable active inductor-based wideband VCO/QVCO design

G. Huang B.-S. KimMicrowaves, Antennas & Propagation, IET

Page (s):830-838 Dec. 2008

National Changhua University Department of Graduate Institute of Integrated Circu

it Design Advisor : Dr. Zhi-Ming LinAdvisee : Shi-Hao Zheng

2

outline Abstract Introduction Active inductor design Programmable wideband VCO/QVCO

design Phase-noise analysis of the proposed VCO

topology Measurement results Conclusions

3

Abstract

Programmable wideband VCO and QVCO which adopt modified gyrator-C-type active inductors with PMOS transistors in the feedback path are presented here.

4

Introduction There are mainly two approaches to integrate the

multimode and multi-band systems.1.Parallel integration of many receivers on the chip le

vel sharing the common blocks each maintaining a signal path.

2.Software-defined radio (SDR) system. Among 1. and 2., either multiple local oscillators (L

O) or a programmable wideband LO is required. The programmable wideband LO is more attractiv

e than the multiple LOs in the modern IC design, due to its characteristic of small chip size and low power dissipation.

5

Active inductor design

SSPPin

mm

o

mm

oin

RSLGSCY

GG

G

GG

CS

GSCY

1

1

21

1

21

122

6

7

8

9

10

Programmable wideband VCO/QVCO design

11

12

13

Phase-noise analysis of the proposed VCO topology

14

15

16

The total noise current of the active inductor-based VCO is much larger than that of the passive LC-VCO.

However, the noise power from the active inductor can be reduced by increasing the feedback resistor Rv or parasitic capacitor Cv, but that lowers the oscillation frequency and frequency tuning range.

Therefore, a trade-off among phase noise, oscillation frequency and tuning range must be considered for the design of wideband VCO based on the active inductor.

17

Measurement results

18

19

20

Conclusions

21

22

Thank you for your attention!