Build a Wireless Soil Moisture Sensor with built-in Micro Energy Harvester

Published  August 1, 2023   



Overview

In today's rapidly evolving world, technological advancements continue to reshape industries, with agriculture and gardening being no exception. Imagine having the ability to effortlessly monitor soil moisture levels in your garden or farm remotely. In this project we are aiming find a solution for that. This innovative solution utilizes a capacitive soil moisture sensor, along with long range LoRa communication without the hassle of manual recharging or battery replacements.

This project utilizes ADP5091, an ultralow power energy harvester PMU with MPPT and charge management from Analog Devices for charging the internal battery from solar energy. We can either use a LiPo battery or a super capacitor for storing the energy. For the controller, we have used the popular ATMega328 MCU, which is widely used in Arduino boards. The moisture sensing is done using a capacitive sensor built around a TLC555C chip. RFM69W module is used for communication. The sensor and LoRa module will only be turned on when necessary. This will help us to reduce energy usage during deep sleep period.

Code File

Code schematicsDownload Button

PCB Gerber File

Gerber FileCode schematics

Components Required

Value Package Manufacturer Digikey Part Number Datasheet Link    Quantity
10nF C603 KYOCERA AVX 478-KGM15AR71H103KTCT-ND KYOCERA AVX datasheet

Datasheet

1
0.1uf C603 Samsung Electro-Mechanics 1276-1935-1-ND Samsung Electro-Mechanics datasheet

Datasheet

8
470pf C603 Walsin Technology Corporation 1292-1438-1-ND Walsin Technology Corporation datasheet

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1
4.7uf C603 Samsung Electro-Mechanics 1276-1784-1-ND Samsung Electro-Mechanics CL10A475KO8NNNC Spec Datasheet

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2
10uF C603 Murata Electronics 490-GRM188R6YA106MA73JCT-ND Murata Electronics GRM188R6YA106MA73 01A datasheet

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1
18pF C603 KEMET 399-C0603C180K4HAC7867CT-ND  KEMET datasheet

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2
LED LED_0603 Harvatek Corporation 3147-B1931NB--20C007614U1930CT-ND Harvatek Corporation B1931NB 20C007614U1930 datasheet

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1
1N4148WS SOD-323 Diodes Incorporated 1N4148WSF-7DICT-ND Diodes Incorporated datasheet

Datasheet

1
22uH IND_VLS3015CX-220M-1 TDK Corporation 445-181504-1-ND TDK Corporation datasheet

Datasheet

1
5.9M R0603 Vishay Dale 541-5.90MHCT-ND Vishay Dale datasheet

Datasheet

2
150K R0603 Vishay Dale 541-150KHCT-ND Vishay Dale 1174914 datasheet

Datasheet

1
4.7M R0603 Vishay Dale 541-4.70MHCT-ND Vishay Dale 11750863 datasheet

Datasheet

1
18M R0603 YAGEO 13-RC0603JR-0718MLCT-ND YAGEO 5918442 datasheet

Datasheet

1
4.7R R0805 Vishay Dale 541-4.7APCT-ND Vishay Dale 3477246 datasheet

Datasheet

1
330R R0603 Bourns Inc. CR0603-JW-331ELFCT-ND Bourns Inc  CR0603-JW 331ELFCT ND datasheet

Datasheet

1
56K R0603 Vishay Dale 541-56.0KHCT-ND datasheet icon

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1
10k R0603 Stackpole Electronics Inc RNCP0603FTD10K0CT-ND datasheet icon

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6
1k R0603 Stackpole Electronics Inc RNCP0603FTD1K00CT-ND datasheet icon

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1
4.22M R0603 RMCF0603FT4M22CT-ND RMCF0603FT4M22CT-ND datasheet icon

Datasheet

2
1.6K R0603 YAGEO 311-1.6KGRCT-ND datasheet icon

Datasheet

1
1M R0603 Walsin Technology Corporation 1292-WR06X105JTLCT-ND datasheet icon

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1
6.65M R0603 Vishay Dale 541-6.65MHCT-ND datasheet icon

Datasheet

2
3.3M R0603 YAGEO 311-3.3MGRCT-ND datasheet icon

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2
100K R0603 YAGEO 311-100KHRCT-ND datasheet icon

Datasheet

1
442K R0603 YAGEO 311-442KHRCT-ND datasheet icon

Datasheet

1
S8050 SOT-23 Micro Commercial Co MMSS8050-H-TPMSCT-ND datasheet icon

Datasheet

2
Solar_Cell Solar Cell SM141K04LV-ND ANYSOLAR Ltd SM141K04LV-ND datasheet icon

Datasheet

1
ADP5091 LFCSP-24-1EP Analog Devices Inc. 505-ADP5091ACPZ-2-R7CT-ND datasheet icon

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1
ATmega328-AU TQFP-32_7x7mm_P0.8mm Microchip Technology ATMEGA328-AU-ND datasheet icon

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1
TLC555C SOIC-8_3.9x4.9mm_P1.27mm Texas Instruments 296-1336-5-ND datasheet icon

Datasheet

1
16MHz Crystal_3225 YIC 3155-16M18PX/XT324-10/10CT-ND datasheet icon

Datasheet

1
SCMT22D505PRBB0 SCMT22D505PRBB0 KYOCERA AVX SCMT22D505PRBB0-ND datasheet icon

Datasheet

1