Positive feedback adiabatic logic is the category under adiabatic logic family. As compared to other families like ECRL, lanes women’s health 2N-2N2P, CAL this PFAL has lowest energy consumption . It is robust against technological parameter variations.
The pulse generator has been designed for widths ranging from 0.25µs to about 4µs with 5 external tuning bits. Since the electrode impedance is known before hand, the input impedance can be set appropriately before implanting the sensor. The wide t1 range provides the ability to trim t1 prior to implantation. This enables us to not only account for variability in process and electrode impedances but also to support different boost converter inductances (Eq. 1). Since the system is meant to implanted, the temperature of the operating environment is well regulated so the variations in pulse widths due to temperature can be ignored. In order to minimize variations in pulse widths due to voltage variations, the transistors used in the logic gates of the pulse generator blocks are 2V transistors that operate above threshold for VDD of 0.8–1.1V.
If each rod has a length L and a resistivity ρ, the resistance of the welded rod is double half four times the same as the resistance of a single rod. Activity in dynamic circuits hence always higher than static. Supply, the diode is reverse biased and hence conducts no current. Therefore, the maximum secondary voltage appears across the diode. 40% efficiency of rectification does not mean that 60% of power is lost in the rectifier circuit. In fact, a crystal diode consumes little power due to its small internal resistance.
The boost converter in this work has been designed to meet the aforementioned requirements. A Charge Pump has been employed to reduce leakage in the boost converter. To ensure system sustainability, the quiescent power of all Control, Timer and Reference circuits has been kept in the 10–100’s of pW range. All the resistors and all the batteries are identical. The total power dissipated in circuit C is twice the total power dissipated in circuit B.
This paper demonstrates some fundamental logic gates employing two phase clocked adiabatic static CMOS logic circuit techniques. We design and simulate NOT, NAND, NOR, and XOR logic gates on the basis of the 2PASCL topology using SPICE implemented using 0.18 ¿m CTX CMOS technology. From the simulation results, we find that 2PASCL inverter logic can save up to 97% of dissipated energy as compared to that with a static CMOS logic at transition frequencies of 10 to 100 MHz.
The PMU, shown in Figure 1, consists of a nW boost converter, pW Control circuits (Φ1 and Φ2 Generation circuits), a Charge Pump along with Timer and Reference circuits. Two electrodes connected to the PMU are inserted into the inner ear to tap the EP. Due to the anatomical constraints in the inner ear, these electrodes need to have tip diameters close to 2 µm causing the resistance of each electrode to be around 200–600 kΩ.
This leakage reduction of course comes at a small cost of generating the VPUMP supply. This will be discussed in detail later in Section IV. Due to the ultra-low power budget, the boost converter used in the PMU operates in the discontinuous conduction mode . While extracting maximum power, the input voltage is typically close to half of the EP, as shown in Figure 2. Therefore, the converter is required to boost up an input voltage of 30–55 mV up to 0.8–1.1 V which is used to power the Control and Timer circuits, a Charge Pump and a duty cycled load (RF-Tx in this work). The RF-Tx load is periodically enabled (once every 40–360 seconds as shown in Figure 2) causing the boost converter output voltage to droop instantaneously.
In electronics, the gains of amplifiers, attenuation of signals, and signal-to-noise ratios are often expressed in decibels. Two principal types of scaling of the decibel are in common use. When expressing a power ratio, it is defined as ten times the logarithm in base 10. That is, a change in power by a factor of 10 corresponds to a 10 dB change in level. When expressing root-power quantities, a change in amplitude by a factor of 10 corresponds to a 20 dB change in level.
Measurements have been made with the PMU connected to electrodes tapping the EP of a anesthetized guinea pig and supplying power to aultra-low-power duty cycled RF-TX . Figure 17 shows the VDD measurements made during three separate surgical experiments for EP values of 80–100mV and electrode impedances in the range of 400kΩ to 1MΩ. Figure 17 shows the corresponding VPUMP measurements. The supply voltages droop when the duty cycled RF-Tx is enabled. For the measurements made, the RF-Tx is enabled either once in 40 to 80 seconds as can be seen in Figure 17. However, for nW operation there are some additional design considerations before we optimize the converter for efficiency.