Home>>News

Introduction to the hottest TPMS pressure sensor n

2022-08-25

Detail

Introduction to TPMS pressure sensor: npp301 and sm5420

automobile tire pressure monitoring system (TPMS) is mainly used to automatically monitor the tire pressure in real time when the car is driving, and to alarm for tire leakage and low pressure. At present, TPMS system has quickly become the basic equipment to avoid accidents, and more and more vehicles control production and quality and install this system in the manufacturing of information industry

tpms is mainly divided into two types, one is indirect TPMS (wheel speed based TPMS). The other is direct TPMS (pressure sensor based tpms1 must ensure its accuracy). In July, 2001, the U.S. Department of transportation and the National Highway Safety Administration jointly evaluated the two existing TPMS systems. The evaluation report believes that the direct TPMS is superior to the indirect TPMS in function and performance, making the development of direct TPMS a popular trend

tpms pressure sensors are based on MEMS technology, mainly including silicon integrated capacitive pressure sensors (such as Freescale MPXY8020 and mpxy8040) and silicon piezoresistive pressure sensors (such as npx1 and npx2 of general novasensor and sm5420 of SMI). Silicon piezoresistive pressure sensor adopts Wheatstone bridge composed of high-precision semiconductor resistance strain gauge as the measuring circuit of electromechanical transformation, and its measurement accuracy can reach 0 03%FS。

silicon piezoresistive pressure sensors (npp301 and sm5420) are suitable for the measurement of most non corrosive gases and dry air. Features: ultra small volume, ultra-low cost surface mount (SO-8) structure, suitable for automatic component mounting. Working temperature: -40 ℃ ~ 125 ℃, static accuracy ＜± 0.2% FSO can provide absolute pressure ranges of 100, 200 and 700KPA. It can be used in automobile tire pressure detection, medical equipment, air conditioning equipment, cable leakage detection, pressure switches and controllers, portable barometers, altimeters and cost elimination instruments Npp301 and sm5420 are surface mounted silicon pressure sensors, which adopt silicon silicon fusion technology and high stability ultra small piezoresistive chip sealed in a plastic shell. It adopts the pin structure of integrated circuit, which can be installed in narrow occasions, so it provides a cheap product for a large number of OEM users. Under the constant voltage power supply, a voltage signal proportional to the input pressure is generated, and users can amplify it or increase its added value through the signal regulation circuit to meet the needs of their own products

npp301 and sm5420 characteristic parameters: pressure range 0 ~ 100KPA ≈ 15, psi0 ~ 200KPa ≈ 30, psi0 ~ 700KPA ≈ 100psi overload 3x Rated pressure electrical performance (25 ℃) power supply 3.0V, maximum 10V. DC input impedance 5000 ± 20% Ω output impedance 5000 ± 20% Ω environmental conditions electrostatic damage (ESD) ＞ 15.010kv operating temperature -40 ~ 125 ℃ physical characteristics weight ≈ 0.10g compatible medium clean, dry Non corrosive gas technical indicators (all test values are relative to 22 ℃, 3V constant voltage power supply) zero output ± 10mV full scale output 60 ± 20mV linearity ± 0.20% FSO hysteresis and repeatability ± 0.10% FSO zero temperature coefficient ± 0.04% FSO/℃ resistance temperature coefficient 0.30%/℃ sensitivity temperature coefficient -0.20vv%fso/℃ zero thermal hysteresis ± 0.10% FSO long-term stability ± 0.20% FSO overall dimension unit: mm (in) Model selection series range package type npp-a100kpa (15psi) so-8npp-a200kpa (30psi) so-8npp-a700kpa (100psi) SO-8 note: 1. This series only provides absolute pressure type (end)