Wide-Supply-Voltage-Range CMOS Bandgap Reference for In Vivo Wireless Power Telemetry

Abstract

The robustness of the reference circuit in a wide range of supply voltages is crucial in implanted devices. Conventional reference circuits have demonstrated a weak performance over wide supply ranges. Channel-length modulation in the transistors causes the circuit to be sensitive to power supply variation. To solve this inherent problem, this paper proposes a new output-voltage-line-regulation controller circuit. When a variation occurs in the power supply, the controller promptly responds to the supply deviation and removes unwanted current in the output path of the reference circuit. The proposed circuit was implemented in a 0.35-μm SK Hynix CMOS standard process. The experimental results demonstrated that the proposed reference circuit could generate a reference voltage of 0.895 V under a power supply voltage of 3.3 V, line regulation of 1.85 mV/V in the supply range of 2.3 to 5 V, maximum power supply rejection ratio (PSRR) of −54 dB, and temperature coefficient of 11.9 ppm/°C in the temperature range of 25 to 100 °C.

Novel Bandwidth Expander Supported Power Amplifier for Wideband Ultrasound Transducer Devices

“…The amplified signal can cause damage to the oscilloscope from a high voltage of 5 V P-P or greater. Therefore, the output signals were attenuated by a 40 dB attenuator, and the performances were measured using an oscilloscope [ 41 , 42 , 43 ]. To measure the performance of the amplifiers, the frequency and input signal amplitudes were adjusted using a function generator.…”

Post-Voltage-Boost Circuit-Supported Single-Ended Class-B Amplifier for Piezoelectric Transducer Applications

“…The inductors at the gate and drain sides are choke inductors (L C = 1 µH), which could minimize the voltage drop when DC bias voltages were used [48][49][50]. In addition, the electrolytic capacitors (C G1 , C D3 , C G6 , and C D8 = 220 µF) and ceramic capacitors (C G2 , C D2 , C G7 , and C D7 = 1000 pF, C G3 , C D1 , C G8 , and C D6 = 47 pF) were used to minimize the noise signals from the DC power supply [51,52]. The input inductors, capacitors, and resistors (L G1 and L G3 = 22 nH, C G4 and C G9 = 560 pF, C G5 and C G10 = 330 pF, L G2 and L G4 = 1000 nH, and R G3 and R G6 = 200 Ω), and output inductors, capacitors, and resistors (L D1 and L D3 = 120 nH, C D4 and C D9 = 330 pF, C D5 and C D10 = 820 pF, L D2 and L D4 = 500 nH, and R D1 and R D2 = 200 Ω) in the firstand second-stage class-B amplifiers were configured for 50 Ω impedance matching conditions at a center frequency of 15 MHz.…”

High-PSRR Wide-Range Supply-Independent CMOS Voltage Reference for Retinal Prosthetic Systems

“…The current paper is an extension of our previous work in [12]. Our last work utilizes the temperature compensation technique, which had been proven to reduce the variation of the reference voltage at higher temperatures.…”

“…The proposed circuit was also evaluated in the full-path retinal prosthetic system shown in Section 3. This system includes on-chip digital controller and stimulator, which is not implemented in [12].…”