Sinusoidal Oscillator Realizations Using Other Types of Current Conveyors - Current Conveyors: Variants, Applications and Hardware Implementations - page 447

y 3

y 2

V 02

DDCC2 DDCC1

z y 2

y 1 z

V 01

y 3 y 1

x

x

R 2 C 1

C 2

R 3

R 1

Fig. 13.8 VM QO proposed by Kumngern and Dejhan [ 28 ]

around 2 % and with power consumption of 7.5 mW. Figure 13.7b shows the SPICE
generated waveforms. These results represent good correspondence with theoretical
expectations.
For some other QO circuits using DVCCs, the readers may refer to [ 22 , 50 ].

13.9 VM Quadrature Oscillator with AGPE Using DDCCs

Several authors have derived sinusoidal oscillator topologies using DDCCs, for
instance see [ 14 , 18 , 19 , 24 ], we present here in Fig. 13.8 VM QO using two
DDCCs, two grounded capacitors and three grounded resistors which was proposed
by Kumngern and Dejhan in [ 28 ]. Assuming ideal DDCCs, a routine circuit
analysis yields the following CE:

1

R 1
R 2

R 2
R 1 ¼

s 2 C 1 C 2 R 1 R 3 þ

sC 2 R 3 þ 0 ð 13 : 19 Þ

The CO and FO from the above equation are given by:

CO R 1 R 2 ð 13 : 20 Þ

:

r

R 2
C 1 C 2 R 3

1
R 1

: ω 0 ¼

ð : Þ

FO 13 21

It can be observed from the above equations that CO can be controlled by R 1 or/ and
R 2 and FO can be varied through R 3 without disturbing CO. Hence, CO and FO are
orthogonally controllable.
The phase difference ˆ between V 01 and V 02 has been found to be:

tan 1 ˆ ¼ ˀ ð ω R 3 C 2 Þ ð 13 : 22 Þ

At ω¼ω 0 , from equation ( 13.22 ), ˆ can be determined as ˆ¼ˀ /2 hence, both V 01