A test strategy for analog filters was proposed. The output voltage and supply current of the circuit were monitored when using the oscillation test technique. The frequency, average value, maximum value and amplitude...A test strategy for analog filters was proposed. The output voltage and supply current of the circuit were monitored when using the oscillation test technique. The frequency, average value, maximum value and amplitude of both output voltage and supply current were taken as test parameters. Tolerance bands of test parameters were analyzed. Fault detectabilities of test parameters were compared and combined, and optimal parameter sets were derived. Experimental results show that both the output voltage and supply current give significant contribution to fault detection. Considering catastrophic, single and double parametric faults, the fault coverage in testing the benchmark circuit can be raised from 90.6% for traditional voltageonly oscillation test strategy to 97.2% by monitoring both output voltage and current parameters.展开更多
A reconfigurable analog baseband circuit for WLAN,WCDMA,and Bluetooth in 0.35μm CMOS is presented. The circuit consists of two variable gain amplifiers(VGA) in cascade and a Gm-C elliptic low-pass filter(LPF). Th...A reconfigurable analog baseband circuit for WLAN,WCDMA,and Bluetooth in 0.35μm CMOS is presented. The circuit consists of two variable gain amplifiers(VGA) in cascade and a Gm-C elliptic low-pass filter(LPF). The filter-order and the cut-off frequency of the LPF can be reconfigured to satisfy the requirements of various applications. In order to achieve the optimum power consumption,the bandwidth of the VGAs can also be dynamically reconfigured and some Gm cells can be cut off in the given application.Simulation results show that the analog baseband circuit consumes 16.8 mW for WLAN,8.9 mW for WCDMA and only 6.5 mW for Bluetooth,all with a 3 V power supply.The analog baseband circuit could provide -10 to +40 dB variable gain,third-order low pass filtering with 1 MHz cut-off frequency for Bluetooth,fourth-order low pass filtering with 2.2 MHz cut-off frequency for WCDMA, and fifth-order low pass filtering with 11 MHz cut-off frequency for WLAN,respectively.展开更多
An analog baseband circuit for a direct conversion wireless local area network(WLAN) transceiver in a standard 0.13-μm CMOS occupying 1.26 mm^2 is presented.The circuit consists of active-RC receiver(RX) 4th orde...An analog baseband circuit for a direct conversion wireless local area network(WLAN) transceiver in a standard 0.13-μm CMOS occupying 1.26 mm^2 is presented.The circuit consists of active-RC receiver(RX) 4th order elliptic lowpass filters(LPFs),transmitter(TX) 3rd order Chebyshev LPFs,RX programmable gain amplifiers (PGAs) with DC offset cancellation(DCOC) servo loops,and on-chip output buffers.The RX baseband gain can be programmed in the range of -11 to 49 dB in 2 dB steps with 50-30.2 nV/(Hz)^(1/2) input referred noise(IRN) and a 21 to -41 dBm in-band 3rd order interception point(IIP3).The RX/TX LPF cutoff frequencies can be switched between 5 MHz,10 MHz,and 20 MHz to fulfill the multimode 802.11b/g/n requirements.The TX baseband gain of the I/Q paths are tuned separately from -1.6 to 0.9 dB in 0.1 dB steps to calibrate TX 1/Q gain mismatches.By using an identical integrator based elliptic filter synthesis method together with global compensation applied to the LPF capacitor array,the power consumption of the RX LPF is considerably reduced and the proposed chip draws 26.8 mA/8 mA by the RX/TX baseband paths from a 1.2 V supply.展开更多
In this work, an original Sallen-Key second-order low-pass filter is first turned into a current-mode one by means of the adjoint network theorem. Two nodal admittance matrices(NAM) of the filter are then educed. Furt...In this work, an original Sallen-Key second-order low-pass filter is first turned into a current-mode one by means of the adjoint network theorem. Two nodal admittance matrices(NAM) of the filter are then educed. Furthermore, these two matrices are expanded through NAM expansion approach, generating one current-mode Sallen-Key filter, which uses two compact voltage differential trans-conductance amplifiers(VDTAs) and two grounded capacitors, implements not only one low-pass transfer function but two band-pass transfer functions, and provides the non-interrelated control between the natural frequency and quality factor. As an example of the synthesized filter, a second-order VDTA filter with fo=1 MHz, Q=1, HLP=-HBP1=HBP2=1 is designed. The used synthesis approach has been confirmed with the help of circuit and computer analysis.展开更多
This paper presents an 8th order active-RC elliptic low-pass filter(LPF) for a direct conversion China Mobile Multimedia Broadcasting(CMMB) tuner with a 1 or 4 MHz -3 dB cutoff frequency(f_(-3dB)).By using a n...This paper presents an 8th order active-RC elliptic low-pass filter(LPF) for a direct conversion China Mobile Multimedia Broadcasting(CMMB) tuner with a 1 or 4 MHz -3 dB cutoff frequency(f_(-3dB)).By using a novel gain-bandwidth-product(GBW) extension technique in designing the operational amplifiers(op-amps), the proposed filter achieves 71 dB stop-band rejection at 1.7f_(-3dB) to meet the stringent CMMB adjacent channel rejection(ACR) specifications while dissipates only 2.8 mA/channel from a 3 V supply,its bias current can be further lowered to 2 mA/channel with only 0.5 dB peaking measured at the filter's pass-band edge.Elaborated common-mode(CM) control circuits are applied to the filter op-amp to increase its common-mode rejection ratio (CMRR) and effectively reject the large signal common-mode interference.Measurement results show that the filter has 128 dBμV_(rms) in-band IIP3 and more than 80 dB passband CMRR.Fabricated in a 0.35-μm SiGe BiCMOS process,the proposed filter occupies a 1.19 mm^2 die area.展开更多
基金the National Key Basic Research and Development (973) Program of China(No. 2005CB321604)the National Natural Science Foundation of China (No. 60633060)
文摘A test strategy for analog filters was proposed. The output voltage and supply current of the circuit were monitored when using the oscillation test technique. The frequency, average value, maximum value and amplitude of both output voltage and supply current were taken as test parameters. Tolerance bands of test parameters were analyzed. Fault detectabilities of test parameters were compared and combined, and optimal parameter sets were derived. Experimental results show that both the output voltage and supply current give significant contribution to fault detection. Considering catastrophic, single and double parametric faults, the fault coverage in testing the benchmark circuit can be raised from 90.6% for traditional voltageonly oscillation test strategy to 97.2% by monitoring both output voltage and current parameters.
基金supported by the National Natural Science Foundation of China(No.60806008)the Fok Ying Tung Education Foundation, China(No.104028).
文摘A reconfigurable analog baseband circuit for WLAN,WCDMA,and Bluetooth in 0.35μm CMOS is presented. The circuit consists of two variable gain amplifiers(VGA) in cascade and a Gm-C elliptic low-pass filter(LPF). The filter-order and the cut-off frequency of the LPF can be reconfigured to satisfy the requirements of various applications. In order to achieve the optimum power consumption,the bandwidth of the VGAs can also be dynamically reconfigured and some Gm cells can be cut off in the given application.Simulation results show that the analog baseband circuit consumes 16.8 mW for WLAN,8.9 mW for WCDMA and only 6.5 mW for Bluetooth,all with a 3 V power supply.The analog baseband circuit could provide -10 to +40 dB variable gain,third-order low pass filtering with 1 MHz cut-off frequency for Bluetooth,fourth-order low pass filtering with 2.2 MHz cut-off frequency for WCDMA, and fifth-order low pass filtering with 11 MHz cut-off frequency for WLAN,respectively.
文摘An analog baseband circuit for a direct conversion wireless local area network(WLAN) transceiver in a standard 0.13-μm CMOS occupying 1.26 mm^2 is presented.The circuit consists of active-RC receiver(RX) 4th order elliptic lowpass filters(LPFs),transmitter(TX) 3rd order Chebyshev LPFs,RX programmable gain amplifiers (PGAs) with DC offset cancellation(DCOC) servo loops,and on-chip output buffers.The RX baseband gain can be programmed in the range of -11 to 49 dB in 2 dB steps with 50-30.2 nV/(Hz)^(1/2) input referred noise(IRN) and a 21 to -41 dBm in-band 3rd order interception point(IIP3).The RX/TX LPF cutoff frequencies can be switched between 5 MHz,10 MHz,and 20 MHz to fulfill the multimode 802.11b/g/n requirements.The TX baseband gain of the I/Q paths are tuned separately from -1.6 to 0.9 dB in 0.1 dB steps to calibrate TX 1/Q gain mismatches.By using an identical integrator based elliptic filter synthesis method together with global compensation applied to the LPF capacitor array,the power consumption of the RX LPF is considerably reduced and the proposed chip draws 26.8 mA/8 mA by the RX/TX baseband paths from a 1.2 V supply.
基金the Natural Science Foundation of Shaanxi Province (2017JM6087)。
文摘In this work, an original Sallen-Key second-order low-pass filter is first turned into a current-mode one by means of the adjoint network theorem. Two nodal admittance matrices(NAM) of the filter are then educed. Furthermore, these two matrices are expanded through NAM expansion approach, generating one current-mode Sallen-Key filter, which uses two compact voltage differential trans-conductance amplifiers(VDTAs) and two grounded capacitors, implements not only one low-pass transfer function but two band-pass transfer functions, and provides the non-interrelated control between the natural frequency and quality factor. As an example of the synthesized filter, a second-order VDTA filter with fo=1 MHz, Q=1, HLP=-HBP1=HBP2=1 is designed. The used synthesis approach has been confirmed with the help of circuit and computer analysis.
文摘This paper presents an 8th order active-RC elliptic low-pass filter(LPF) for a direct conversion China Mobile Multimedia Broadcasting(CMMB) tuner with a 1 or 4 MHz -3 dB cutoff frequency(f_(-3dB)).By using a novel gain-bandwidth-product(GBW) extension technique in designing the operational amplifiers(op-amps), the proposed filter achieves 71 dB stop-band rejection at 1.7f_(-3dB) to meet the stringent CMMB adjacent channel rejection(ACR) specifications while dissipates only 2.8 mA/channel from a 3 V supply,its bias current can be further lowered to 2 mA/channel with only 0.5 dB peaking measured at the filter's pass-band edge.Elaborated common-mode(CM) control circuits are applied to the filter op-amp to increase its common-mode rejection ratio (CMRR) and effectively reject the large signal common-mode interference.Measurement results show that the filter has 128 dBμV_(rms) in-band IIP3 and more than 80 dB passband CMRR.Fabricated in a 0.35-μm SiGe BiCMOS process,the proposed filter occupies a 1.19 mm^2 die area.