Friend (omi-dk2) Hardware Schematics
Schematics for the Friend (omi-dk2) wearable device featuring an nRF52840 SoC, PDM microphone, audio amplifier, 6-axis IMU, and microSD storage.
Overview
This schematic document details the hardware architecture for the Friend (omi-dk2) platform. The design is based on the Nordic Semiconductor nRF52840-QIAA-R Bluetooth 5.4 SoC. Key subsystems include an audio interface with a MEMSensing MSM261D3526H1CPM PDM microphone and a Maxim Integrated MAX98357A Class D amplifier. Motion sensing is provided by an STMicroelectronics LSM6DS3TR-C 6-axis IMU. Power management is handled via a USB-C interface, an SGM40567 battery charger, and an SGM2040 3.3V LDO. Additional features include a 2Mbit Puya QSPI flash, a MicroSD card slot, an RGB LED, and support for a vibration motor.
Use Cases
- Wearable audio device development
- Bluetooth-enabled sensor platform prototyping
- Portable data logging with MicroSD storage
- Voice-activated IoT peripheral design
Topics
Referenced Parts
SDM20U40-7
Diodes Incorporated
D1 SDM20U40-7 40V 250mA
MAX98357A
Maxim Integrated
U4 MAX98357A
P25Q16SH-UXH-IR
Puya Semiconductor
U7 P25Q16SH-UXH-IR
SGM2040-3.3YUDH4G/TR
SGMicro
U6 SGM2040-3.3YUDH4G/TR 250mA
SGM40567-4.2XG/TR
SGMicro
U5 SGM40567-4.2XG/TR
USB-31C-F-16P-L7.35
HRO
USB1 USB-31C-F-16P-L7.35
KH5220-A36
Kinghelm
ANT1 KH5220-A36
LP0404N3T5G
LRC
Q1 LP0404N3T5G
MSM261D3526H1CPM
MEMSensing
MIC1 MSM261D3526H1CPM
LQM18FN100M00
Murata
L3 LQM18FN100M00
FC-B1010RGBT-HG
NationStar
RGB6 FC-B1010RGBT-HG
BC817W-25W
Nexperia
Q2 BC817W-25W 25V,500mA
SX1801CCR
Semtech
U2 SX1801CCR 5.5V 2A
ST-TF-003D-A
Suntech
J1 ST-TF-003D-A
TS-1001S
XKB Connectivity
K1 TS-1001S
| NRF52840-QIAA-R | Nordic Semiconductor | U1 NRF52840-QIAA-R |
| LSM6DS3TR-C | Stmicroelectronics | U3 LSM6DS3TR-C |
| SDM20U40-7 | Diodes Incorporated | D1 SDM20U40-7 40V 250mA |
| MAX98357A | Maxim Integrated | U4 MAX98357A |
| P25Q16SH-UXH-IR | Puya Semiconductor | U7 P25Q16SH-UXH-IR |
| SGM2040-3.3YUDH4G/TR | SGMicro | U6 SGM2040-3.3YUDH4G/TR 250mA |
| SGM40567-4.2XG/TR | SGMicro | U5 SGM40567-4.2XG/TR |
| USB-31C-F-16P-L7.35 | HRO | USB1 USB-31C-F-16P-L7.35 |
| KH5220-A36 | Kinghelm | ANT1 KH5220-A36 |
| LP0404N3T5G | LRC | Q1 LP0404N3T5G |
| MSM261D3526H1CPM | MEMSensing | MIC1 MSM261D3526H1CPM |
| LQM18FN100M00 | Murata | L3 LQM18FN100M00 |
| FC-B1010RGBT-HG | NationStar | RGB6 FC-B1010RGBT-HG |
| BC817W-25W | Nexperia | Q2 BC817W-25W 25V,500mA |
| SX1801CCR | Semtech | U2 SX1801CCR 5.5V 2A |
| ST-TF-003D-A | Suntech | J1 ST-TF-003D-A |
| TS-1001S | XKB Connectivity | K1 TS-1001S |