[Show abstract][Hide abstract] ABSTRACT: This article presents a divide-by-4 quadrature injection locked frequency divider (ILFD) employing tunable active inductors (TAIs), which are used to extend the locking range and to reduce die area. The CMOS ILFD is based on a quadrature voltage-controlled oscillator (QVCO) with NMOS cross-coupled switching pairs, two tail MOSFETs and TAI-C tanks, and was fabricated in the 0.35 m 2P4M CMOS technology. The divide-by-4 LC-tank ILFD is performed by injecting an external signal to the common gate of tail MOSFETs of two coupled VCOs. Measurement results show that at the supply voltage of 2.3 V, the divider free-running frequency is tunable from 0.36 to 1.51 GHz, and at the incident power of 0 dBm the locking range is about 4.6 GHz, from the incident frequency 1.44-6.04 GHz. The core power consumption is 29.37 mW. The die area is 0.976 × 0.812 mm2.
No preview · Article · Dec 2009 · International Journal of Electronics
[Show abstract][Hide abstract] ABSTRACT: This letter presents a wide-locking range, body-injected, injection locked frequency divider (ILFD) with tunable active inductors (TAIs) and variable division ratio. The ILFD was fabricated in the 0.18 mum 1P6M CMOS technology, and it has the modulus of 2, 3, 4, and 5, and can be used as a first-harmonic injection-locked oscillator (ILO). The divide-by-3 function is performed by injecting differential a signal to the bodies of cross-coupled transistors in the VCO. At the supply voltage of 1.5 V, the free-running divider is tunable from 0.53 to 1.72 GHz. At the incident power of 0 dBm the operation range in the first-harmonic ILO is from the incident frequency 0.53 to 3.2 GHz. The operation range in the divide-by-3 (divide-by-2) mode is about 3.59 (4.13) GHz, from the incident frequency 1.55 to 5.14 (0.87 to 5.0) GHz.
No preview · Article · Feb 2009 · IEEE Microwave and Wireless Components Letters