39results about How to "Eliminate zero drift" patented technology

The invention discloses an electrophysiological catheter with a pressure sensing function. By the electrophysiological catheter, temperatures can be compensated according to temperature changes in theapplication, zero temperature drifts of contact pressure measurements can be remarkably eliminated, measuring errors can be reduced, the stability of the contact pressure measurements can be improved, and the production cost of the electrophysiological catheter can be reduced. The electrophysiological catheter comprises a head electrode, a second electrode, a pressure sensor, a catheter body, a handle, a connector and an internal circuit board. The head electrode, the second electrode and the pressure sensor are sequentially arranged at the front end of the catheter body. The catheter body isinserted into the human body from the outside, and the rear end of the catheter body is connected with the handle to facilitate holding. The connector is arranged at the tail end of the handle, and is constructed as a data and power combined interface to be connected with a radio frequency energy source, a power source and a data transmission interface. The internal circuit board is arranged in the handle, is provided with a pressure detecting circuit to receive signals of the pressure sensor, and is also provided with a micro processing unit to acquire pressure data according to the signalsof the pressure sensor.

The invention relates to a nonlinear correction microphone. The nonlinear correction microphone comprises a sensitive film, a base main body, a low-sensitivity rear polar plate, a high-sensitivity rear polar plate, a shielding cavity, a high-sound-pressure output electrode, a high-sensitivity output electrode and an amplification circuit board. A capacitor microphone with high sound pressure and low sensitivity and a capacitor microphone with low sound pressure and high sensitivity are compounded together, the same sound pressure is detected, the two capacitors share one diaphragm; the small area of the center of the rear pole plate is the rear pole of the high-sound-pressure capacitor microphone; the large area of the periphery of the rear pole plate is the rear pole of the low-sound-pressure condenser microphone, the output of the low-sound-pressure condenser microphone is approximately linear, the output of the high-sensitivity condenser microphone is nonlinear, and the output of the high-sensitivity condenser microphone is corrected by using the output signal of the high-voltage condenser microphone in the amplifier.

The invention belongs to the technical field of isolation amplifier circuits, and particularly relates to a programmable gain isolation amplifier circuit and an implement method thereof. The programmable gain isolation amplifier circuit comprises an isolation unit U1 and a programmable gain amplifier circuit, wherein the isolation unit U1 comprises an input end, a conversion capacitor, a micro-electronic digital single-pole double-throw switch, gating signals, and control signals of the micro-electronic digital switch, and the programmable gain amplifier circuit comprises a precise integrated operational amplifier, a programmable resistor network and a gain measuring circuit. The programmable resistor network is composed of digital potentiometers, and the gain measuring circuit comprises a digital switch, standard voltage and the control signals of the digital switch. The programmable gain isolation amplifier circuit can achieve complete isolation between a signal end and the amplifier, can overcome the zero-shift phenomenon of the amplifier circuit, is strong in continuity of gain selection, and can remarkably improve amplification precision.