M. Nakamura et al., OVER-30-GHZ LIMITING AMPLIFIER ICS WITH SMALL PHASE DEVIATION FOR OPTICAL COMMUNICATION-SYSTEMS, IEEE journal of solid-state circuits, 31(8), 1996, pp. 1091-1099
For a high-speed limiting amplifier with small phase deviation, a new
design technique using a uniplanar passive balun and a narrow-band mat
ching network is proposed. It is revealed that a device with small bia
s-dependence of parasitic capacitances, such as a high electron mobili
ty transistor (HEMT), and a differential operation using passive balun
s enables phase deviations at very high frequency to be reduced. Furth
ermore, suppressing harmonics can reduce phase deviation in a limiting
amplifier, which operates in the highly nonlinear region. To verify t
hese design techniques, two types of limiting amplifier IC's using an
InP HEMT and AlGaAs/GaAs BCT technology were designed and fabricated.
These IC's feature narrow-band matching circuits for input and output
using transmission lines and uniplanar CPW-slot transition balms for d
ifferential signals. The devices achieved high frequency operation of
over 30 GHz with small phase deviations.