scholarly journals Current mismatch reduction in charge pumps using regulated current stealing-injecting transistors for PLLs

Author(s):  
Mohd Khairi Zulkalnain ◽  
Yan Chiew Wong

A charge pump for phase locked loops (PLL) with a novel current mismatch compensation technique is proposed. The proposed circuit uses a simple yet effective current stealing-injecting (CSI) technique and feedback to reduce mismatch between the negative-channel-metal-oxide (NMOS) and positive-channel-metal-oxide (PMOS) transistors. The current stealing transistor steals the current from a replica branch and mirrors it to the output where it is added to the output branch by the injecting transistor. A feedback mechanism is used to set the drain voltages of both branches to be equal and mitigate channel length modulation and ensure high accuracy. The proposed circuit was designed on Silterra 130nm technology and simulated using Cadence Spectre. The simulation results show that the proposed circuit yields a maximum of 0.107% and minimum of 0.00465% current mismatch while operating at a low supply voltage of 800mV for a range of 100mV to 700mV. The proposed design uses only one rail-to-rail op amp for compensating the mismatch and an addition of 4 transistors and utilizing 75% of the supply voltage for high voltage controlled oscillator (VCO) tuning range.


2019 ◽  
Vol 28 (08) ◽  
pp. 1950125
Author(s):  
Jianqun Ding ◽  
Lijun Huang ◽  
Xianwu Mi ◽  
Dajiang He ◽  
Shenghai Chen ◽  
...  

In this paper, a full PMOS Colpitts quadrature voltage-controlled oscillator (QVCO) topology, suitable for low supply voltage and low power dissipation, is presented. For an enhanced voltage swing under a low supply voltage, the capacitive-feedback technique is employed. Quadrature coupling is achieved by employing direct bulk coupling technique, leading to reduction in both power and chip area. The proposed QVCO covers a 5% tuning range between 2.325 GHz and 2.435 GHz, and the phase noise is [Formula: see text]128.2 dBc/Hz at 1-MHz offset from the 2.34-GHz carrier while consuming only 0.535 mW from 0.55-V supply voltage, yielding a figure-of-merit (FoM) of 198 dBc/Hz.



2013 ◽  
Vol 380-384 ◽  
pp. 3275-3278
Author(s):  
Zhan Peng Jiang ◽  
Rui Xu ◽  
Hai Huang ◽  
Chang Chun Dong

An rail-to-rail operational amplifier is presented in this paper, which is designed by with two op amp, the first level of the structure is the complementary differential structure which will providing input for the operational amplifier, the second level is designed with the structure of folding cascode to get a high gain. The operational amplifier is designed with the TSMC 0.35u m3.3VCMOS mixed analog-digital technology library. The simulated results show that the operational amplifier has a DC gain of 110dB,a GBW of 9.5MHz,a static power dissipation of 0.95mW,a phase margin of 73°,a voltage slew rate of 8.2V/μS,an input and output range of 0-3.3V,when operating at 3.3V power supply and a 20pF output load.





Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1009
Author(s):  
Rui Guo ◽  
Zhenghao Lu ◽  
Shaogang Hu ◽  
Qi Yu ◽  
Limei Rong ◽  
...  

A charge pump (CP) that has low current mismatch to reduce the locking time of the Phase-Locked Loop (PLL) is proposed. The design is promising in 5G applications with the capabilities of fast settling and low power consumption. In this design, a charge pump architecture consists of an operational power amplifier (OPA), switches, three D flip-flops (DFFs) and passive devices. A phase error compensation technique is introduced in the charge pump to reduce the locking time. The current mismatch, which is mainly due to the leakage current, is below 1% for a large output voltage headroom of 84% of the supply voltage. An 18.4% reduction in the settling time is realized by the proposed design.



Author(s):  
AAMNA ANIL ◽  
RAVI KUMAR SHARMA

A charge pump is a kind of DC to DC converter that uses capacitors as energy storage elements to create a higher or lower voltage power source. Charge pumps make use of switching devices for controlling the connection of voltage to the capacitor. Charge pumps have been used in the nonvolatile memories, such as EEPROM and Flash memories, for the programming of the floating-gate devices. They can also be used in the low-supply-voltage switched-capacitor systems that require high voltage to drive the analog switched. This paper includes voltage analysis of different charge pumps. On the basis of voltage analysis a new charge pump is proposed.





Sign in / Sign up

Export Citation Format

Share Document