通信单片机外文翻译---一个完全植入式无线压力监测系统的开发-单片机(编辑修改稿)

通信单片机外文翻译---一个完全植入式无线压力监测系统的开发-单片机(编辑修改稿)内容摘要：

the total device volume is minimized, as the battery is typically the largest ponent. Several groups have developed and tested devices that detect dynamic blood pressure in the femoral artery or aorta of animal models (Najafi and Ludomirsky 2020。 Schlierf et al. 2020). However the transmission range is often limited to centimeters (Najafi and Ludomirsky 2020。 Schlierf et al. 2020) and the sensor can only transmit data when it is exposed to RF energy. This often limits the measurements to discrete points in time or tethers the patient to an antenna at all times for continuous measurements (CardioMEMS 2020。 Walton and Krum 2020). Here we present a different approach to monitor ambulatory pressures, which consists of a micromachined pressure die, amplifying electronics, microcontroller, wireless transmitter, and battery, and municates with a personal digital assistant (PDA) or puter. 2 Methods and materials The pressure sensing platform is divided into three parts: the pressure sensing catheter lead, the sensor node (Fig. 1), and the PDA or puter receiver. The fabrication of each of these parts is discussed below: Catheter lead The catheter lead houses the pressure sensor and connects it to the sensor node (Fig. 2). It consists of a piezoresistive pressure sensor (Silicon Microstructures 5108) measuring mm affixed onto a ceramic printed circuit board (PCB) with UV epoxy (Masterbond UV10). The die was chosen for its size, sensing range, and precision, with a sensitivity of mV/psi/V. The strain gauges on the die are configured in a temperaturepensated Wheatstone bridge. The chip was then wirebonded (West Bond 7402C) to contact pads on the substrate board. Four individually insulated platinum–iridium (Pt–Ir) wires threaded through a French ( mm) catheter were soldered to leads on the board connected to the contact pads. UV epoxy was applied over all contact and solder pads on the substrate board and chip and cured for 8 min to prevent any of the Pt–Ir wires or wirebonds from breaking contact. A gold cap with four wedgeshaped holes cut out of the side was affixed with UV epoxy onto the PCB over the pressure die to protect the chip. The four Pt–Ir wires were wound around a hightensile insulating polyester core and threaded through tygon tubing. This assembly was threaded through silicone tubing prior to soldering. Fig. 1 The implanted device after fully being fully packaged. The pressure sensor is housed at the end of a French catheter, which is implanted directly into the bladder or peritoneal cavity. The other end of the catheter is connected into the sensor node, which consists of the dot mote (microcontroller and wireless transmitter), the amplifying electronics, and battery. The device is wrapped in LDPE film and molded in medicalgrade PDMS. Fig. 2 Artist’s rendition of catheter lead tip. (a) Shows the lead tip unpackaged. A mercial pressure die is affixed and wirebonded onto a PCB substrate. Four Pt–Ir wires fed through the catheter are soldered onto the PCB. (b) Depicts the lead after packaging. A gold lid covers and protects the chip and wirebonds. Cellophane is wrapped around the lead。 PDMS is molded around it to make it biopatible Sensor node The sensor node consists of three ponents: amplifying electronics, microcontroller and wireless transmitter, and the battery. The free end of the catheter lead is soldered onto a customdesigned circuit board. On this circuit board are a quad micropower, single supply operational amplifier (Texas Instruments TLV2764), a V voltage regulator chip (Analog Devices REF192), and a single pole, doublethrow (SPDT) magic reed switch to turn the device on and off (Hamlin) (Lin 2020). The voltage regulator chip sets the supply voltage powering the device and other electronics to V to prevent any variations in signal from the pressure die due to variations in battery voltage. The operational amplifiers were configured to null any offset from t。