Summary

The board of wireless module TWE-Lite, temperature & humidity I2C sensor SHT21 dissipates 7.3 uA only on waiting. It undergoes field test now.

Motive

Building wireless temperature & humidity sensor, do field test. It adopts sealed enclosure with fastening screws, as one-coin box seal deteriorates in a few years.

要約

原理的に湿度センサは加熱が必要にもかかわらず，組み立てた回路の待機消費電流は 7.3 uA に過ぎない。現在フィールド試験を実施中。

経緯目的

温湿度センサ SHT21 のフィールド試験を行う。100 均ケースのシールが経年劣化するため，防水ケースを採用したワイヤレスセンサを製作する。

I assembled wireless module TWE-Lite with wire antenna, temperature and humidity sensor on Linkman universal board LUPCB-7247H (Size: 72x47 mm) in the drip proof box as shown in Photo1. I drew the layout not to interfere using CAD JWW. I worked 3 holes on the bottom containning the board, 3 holes for cable and sensor box. Photo2 shows the enclosure. The attached sensor box contains I2C sensor SHT21.

I loaded TWE (Tocos Wireless Engine) App_Tag to work I2C sensor and comunicate Monostick (Parent). The wired board dissipates 7.3 uA only at 3.3V. Humidity sensor has to be heated in princeple, the waiting current is little. The minimum pull-up working voltage is 2.08 V. The pull-down is 2.06 V. (Measurement date: 2017-09-08)

Photo 2 shows the device appearance. The top cover closes with rubber seal. The thickness is 2.7 to 2.8 mm by micrometer. It is thicker than old one 1.4 to 1.5 mm.

I can sell the battery holder assembly or the customized cable assembly with EI connector.
EI コネクタを取り付けたケーブルハーネスとかバッテリホルダの販売可能です。