PH Orp Board
About the PH Orp Board
PH Orp Board is an open source PCB design by Loic74650, published on GitHub under the MIT license. It is a 2-layer board measuring 47 × 62.1 mm, with 44 components from 16 distinct parts.
Other key parts include the LMP7721MA/NOPB, ADS1115IDGS and ADM3260. By type, the board carries 24 resistors, 13 capacitors, 4 ICs and 3 connectors.
From the project
A 16 bits, two-channels, analog to digital convertion board with galavnic isolation to measure pH and Orp levels in pools and similar environments
This project is based on the original project from Roberto Buti: https://github.com/reef-pi/pH-Board. This modified version features a double input for simultaneous pH and Orp measurements on the same board, based on the ADS1115 IC. This board is an ideal companion to the PoolMaster project: https://github.com/Loic74650/PoolMaster. The 5Volts power supply to this board should be low noise and low drift (sorry no spec). A alternative (and likely better) routing of the board was performed by @Gixy31 and is available here: https://github.com/Gixy31/ESP32-PoolMaster/tree/main/pH_Orp%20Board%20V2
Main components on the PH Orp Board
PH Orp Board bill of materials (BOM)
44 components, 16 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 2 | LMP7721MA/NOPB | SOIC127P599X175-8N | U1, U2 |
| 1 | ADS1115IDGS | VSSOP-10_3x3mm_P0.5mm | U3 |
| 1 | ADM3260 | SOP65P780X200-20N | U4 |
| 2 | Conn_Coaxial | BNC_Amphenol_B6252HB-NPP3G-50_Horizontal | J1, J2 |
| 1 | Conn_01x04_Male | PinHeader_1x04_P2.54mm_Vertical | J3 |
| 7 | 100nF | C_0603_1608Metric_Pad1.08x0.95mm_HandSolder | C1, C2, C3, C4, C9, C10, C12 |
| 4 | 1uF | C_0603_1608Metric_Pad1.08x0.95mm_HandSolder | C5, C6, C7, C8 |
| 2 | 10uF | C_1210_3225Metric_Pad1.33x2.70mm_HandSolder | C11, C13 |
| 2 | 100K | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R1, R2 |
| 2 | 51K | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R3, R4 |
| 1 | 350K | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R5 |
| 1 | 1M | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R6 |
| 12 | 10K | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R7, R8, R9, R10, R11, R12, R13, R14 +4 |
| 4 | 0 | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R15, R16, R17, R18 |
| 1 | R30.9K | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R21 |
| 1 | R10K | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | R22 |
PH Orp Board design files
The KiCad project lives in the Loic74650/pH_Orp_Board repository on GitHub; these links point at the commit this page was built from.
PH Orp Board: common questions
How big is the PH Orp Board?
The PH Orp Board measures 47 × 62.1 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the PH Orp Board?
44 components, from 16 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the PH Orp Board design files?
From the Loic74650/pH_Orp_Board repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the PH Orp Board design in my own project?
Yes, under the terms of its MIT license, which Loic74650 chose for the repository.