Espressif ESP32-S3-MINI-1
Low Cost Dual Camera Smart Glasses
Overview
An ultra-low-cost DIY smart glasses prototype featuring dual daylight zoom and night vision cameras integrated into standard frames with temple-concealed batteries.
Ali
System architecture
POWER
MCU
SENSOR
RF
- BATTERY → POWERPowerBattery feeds raw DC to PMIC
- POWER → MCU_LEFTPowerRegulated power to left MCU
- POWER → MCU_RIGHTPowerRegulated power to right MCU
- MCU_LEFT → CAMERA_OPTICAL_ZOOMSPICamera control and high-speed image data pipeline
- MCU_RIGHT → CAMERA_NIGHT_VISIONGPIONight vision sensor control and parallel video data capture
- MCU_LEFT → MCU_RIGHTUARTInter-MCU synchronization and telemetry via flex PCB bridge
Bill of materials
| Part number | Type | Component | Manufacturer | Package | Qty | Datasheet | Match |
|---|---|---|---|---|---|---|---|
| BQ25157YFPR | POWER | Custom 3.7V Li-Ion Thin Cell + PMIC (BQ25157) Manages battery charging, system power rails (3.3V, 1.8V), and over-current protection within temple arm | Texas Instruments | 20-XFBGA, DSBGA | 1 | Matched | |
| ESP32-S3-MINI-1-N4R2 | MCU | Espressif ESP32-S3-MINI-1 Left temple main controller handling 5X optical zoom camera capture, ISP processing, and Wi-Fi/BLE streaming | Espressif Systems | SMD | 1 | Matched | |
1 alternatives consideredAI verified | |||||||
| ESP32-S3-MINI-1-N4R2 | MCU | Espressif ESP32-S3-MINI-1 Right temple co-processor managing miniature night vision camera and peripheral sensor monitoring | Espressif Systems | SMD | 1 | Matched | |
1 alternatives consideredAI verified | |||||||
| LC898212AXD | SENSOR | Miniature Periscope 5X Optical Zoom Module (OV64B + LC898212AXD) Captures high-resolution consumer photography with true 5X optical zoom via folded optics and VCM driver | OmniVision | — | 1 | Pending | |
3 alternatives consideredAI verified | |||||||
| OV9281 | SENSOR | Miniature NIR Camera Sensor (OV9281 / IR sensitive) Provides low-light and miniature night vision image acquisition | OmniVision | — | 1 | Matched | |
| ESP32-S3 | RF | ESP32-S3 Integrated Wi-Fi / BLE 5.0 Radio Handles wireless video streaming, photo transfer, and companion smartphone app connectivity | Espressif Systems | 56-VFQFN Exposed Pad | 1 | Matched | |
4 alternatives consideredAI verified | |||||||
| BQ25157YFPR | POWER | Temple-Concealed Li-Ion Rechargeable Battery Cell Stores electrical energy to support at least 1 hour of continuous recording | Texas Instruments | 20-XFBGA, DSBGA | 1 | Matched | |
Build guide
6-8 hoursAdvanced
1
Procurement & Preparation
- Source all electronic components and modular sub-assemblies including BQ25157YFPR PMIC, two ESP32-S3-MINI-1-N4R2 modules, OV64B 5X Periscope Optical Zoom camera, and OV9281 NIR camera sensor.
- Prepare standard eyeglass frames with designated internal channels in the left and right temples for housing slim PCB layouts and custom thin Li-Ion battery cells.
2
Hardware Assembly & Wiring
- Solder the custom 3.7V Li-Ion thin cell to the BQ25157 PMIC power management board, verifying proper VBAT and GND polarity.
- Mount the left ESP32-S3-MINI-1 module into the left temple arm and wire power rails (3.3V, GND) from the PMIC along with MIPI_CSI and I2C lines to the OV64B 5X Optical Zoom camera module.
- Mount the right ESP32-S3-MINI-1 module into the right temple arm, connect power rails, and interface the DVP data and I2C bus to the OV9281 Miniature NIR Camera Sensor.
- Run inter-temple communication lines by connecting UART TX, RX, and GND signals between the left MCU and right MCU across the bridge or hinge assembly.
3
Firmware Setup
- Flash the left ESP32-S3-MINI-1 with firmware supporting OV64B camera capture, VCM driver lens control, Wi-Fi/BLE streaming stacks, and UART master protocol.
- Flash the right ESP32-S3-MINI-1 with slave firmware managing OV9281 low-light image acquisition, peripheral sensor polling, and UART communication with the master controller.
4
Testing & Calibration
- Perform power-on self-test (POST) using a digital multimeter to verify 3.3V and 1.8V regulated power rails from the BQ25157 PMIC under load.
- Calibrate the 5X optical zoom VCM driver (LC898212AXD) and test dual camera streaming performance by connecting via Wi-Fi/BLE to a companion smartphone app.
Document
Low Cost Dual Camera Smart Glasses
An ultra-low-cost DIY smart glasses prototype featuring dual daylight zoom and night vision cameras integrated into standard frames with temple-concealed batteries.
Executive Summary
This reference design defines the system architecture, critical component candidates, risk register, and validation path for Smart Glasses Prototype. It is a system-level design deliverable; verify critical claims with manufacturer evidence and prototype testing before production release.
Design Overview
Requirements Coverage
| Requirement | Architecture coverage | Status |
|---|---|---|
| Consumer photography with up to 5X true optical zoom | MCU_LEFT, CAMERA_OPTICAL_ZOOM | Covered |
| Casual daily video/image recording | MCU_LEFT, CAMERA_OPTICAL_ZOOM, WIFI_BLE | Covered |
| Miniature night vision camera integration | MCU_RIGHT, CAMERA_NIGHT_VISION | Covered |
| Discreet form factor fitting standard glasses frames | POWER, BATTERY, MCU_LEFT, MCU_RIGHT | Covered |
| Item | Details |
|---|---|
| Product Type | Smart Glasses Prototype |
| Key Functions | Consumer photography with up to 5X true optical zoom, Casual daily video/image recording, Miniature night vision camera integration, Discreet form factor fitting standard glasses frames |
| Power Source | Li-Ion Battery |
| Connectivity | |
| Size | Strictly standard glasses frame dimensions with concealed temple arm electronics |
| Environment | wearable |
| Difficulty | Advanced |
| Est. Time | 6-8 hours |
System Architecture
Power Topology: Single 3.7V Li-Ion battery supplies a central PMIC generating regulated 3.3V and sub-rails distributed across left and right temple arms via flexible printed circuit (FPC) hinge bridges.
Module List
| Module ID | Type | Name | Function | Voltage |
|---|---|---|---|---|
| POWER | POWER | Custom 3.7V Li-Ion Thin Cell + PMIC (BQ25157) | Manages battery charging, system power rails (3.3V, 1.8V), and over-current protection within temple arm | 3.7V |
| MCU_LEFT | MCU | Espressif ESP32-S3-MINI-1 | Left temple main controller handling 5X optical zoom camera capture, ISP processing, and Wi-Fi/BLE streaming | 3.3V |
| MCU_RIGHT | MCU | Espressif ESP32-S3-MINI-1 | Right temple co-processor managing miniature night vision camera and peripheral sensor monitoring | 3.3V |
| CAMERA_OPTICAL_ZOOM | SENSOR | Miniature Periscope 5X Optical Zoom Module (OV64B + LC898212AXD) | Captures high-resolution consumer photography with true 5X optical zoom via folded optics and VCM driver | 2.8V/1.8V |
| CAMERA_NIGHT_VISION | SENSOR | Miniature NIR Camera Sensor (OV9281 / IR sensitive) | Provides low-light and miniature night vision image acquisition | 2.8V/1.8V |
| WIFI_BLE | RF | ESP32-S3 Integrated Wi-Fi / BLE 5.0 Radio | Handles wireless video streaming, photo transfer, and companion smartphone app connectivity | 3.3V |
| BATTERY | POWER | Temple-Concealed Li-Ion Rechargeable Battery Cell | Stores electrical energy to support at least 1 hour of continuous recording | 3.7V |
Power Tree and Signal Interfaces
| From | To | Type | Interface / rail | Voltage |
|---|---|---|---|---|
| BATTERY | POWER | power | Power | 3.7V |
| POWER | MCU_LEFT | power | Power | 3.3V |
| POWER | MCU_RIGHT | power | Power | 3.3V |
| MCU_LEFT | CAMERA_OPTICAL_ZOOM | power | SPI | 3.3V |
| MCU_RIGHT | CAMERA_NIGHT_VISION | power | GPIO | 3.3V |
| MCU_LEFT | MCU_RIGHT | power | UART | 3.3V |
Design Schemes
Dual ESP32-S3 Distributed Temple Architecture ★
Distributes processing and dual cameras across left and right temple arms using dual ESP32-S3 modules connected via internal flexible wiring.
Trade-offs: Offers balanced weight distribution and modular routing, but requires reliable high-speed flex interconnects across the hinge.
Key IC selection
Main compute and optical camera controller
- Need: Dual-core Xtensa LX7 running up to 240MHz with native Wi-Fi/BLE, high-speed SPI/I2C, and sufficient GPIOs for MIPI bridge/camera interface within ultra-low standby power envelope
- Class: Wi-Fi/BLE Integrated Low-Power Microcontroller
- Shortlist: Espressif ESP32-S3 Series, Nordic nRF5340 + external Wi-Fi chip
- Pick: Select catalog MPN based on integrated flash size (e.g., 8MB/16MB QSPI Flash) and compact module package dimensions fitting standard temple width.
Battery charger and system power rail management
- Need: Linear/Buck charger supporting extremely low termination current for thin Li-Ion cells, integrated load switches or LDOs for multi-rail output (3.3V, 1.8V) with small footprint
- Class: I2C Controlled Nano-Power Battery Charger with Power Path
- Shortlist: TI BQ25157, Analog Devices LTC4124
- Pick: Select catalog MPN based on quiescent current draw, programmable LDO output voltages, and DSBGA package size constraints for temple integration.
Periscope optical zoom actuator driver
- Need: Precise closed-loop or open-loop control of Voice Coil Motor (VCM) for optical lens positioning supporting 5X zoom optics with low power consumption
- Class: Single-Axis / Multi-Axis VCM Lens Driver IC with I2C Interface
- Shortlist: Rohm LC898212AXD, TDK Chirp / Analog VCM drivers
- Pick: Select catalog MPN matching the electrical resistance and stroke requirements of the OV64B periscope module VCM actuator.
Risk register
| ID | Area | Severity | Detail | Mitigation |
|---|---|---|---|---|
| r1 | thermal | high | Dual ESP32-S3 microcontrollers running Wi-Fi streaming alongside the OV64B ISP processing in a sealed temple arm will generate localized hotspots exceeding skin-contact temperature limits (48°C). | Implement aggressive duty-cycling, dynamic frequency scaling (DFS) for the ESP32-S3, and utilize internal copper planes within the temple PCB as thermal spreaders. |
| r2 | emi | high | High-frequency MIPI camera serial interfaces and Wi-Fi 2.4GHz RF transceivers operating in close proximity inside both temples risk desensitizing GNSS/BLE receivers and causing image line-artifacts. | Enforce strict ground shielding on flexible printed circuits (FPCs) connecting temples, use differential routing with ground guards for camera interfaces, and place ferrite beads on shared power rails. |
| r3 | mech | med | Integrating a mechanical periscope 5X zoom module and VCM driver into a slender consumer glasses temple risks high failure rates under mechanical drop or daily flexing stress. | Design internal elastomer shock absorbers around the periscope camera module and specify robust housing tolerances to isolate mechanical chassis stress from optical elements. |
Bring-up and Validation Plan
- Power-off inspection and rail resistance checks
- Current-limited first power-up; verify every rail before enabling loads
- Validate interfaces and timing one subsystem at a time
- Run thermal, fault-injection, EMC pre-scan, and endurance tests for the target environment
Key Components
6/7 modules matched to real parts. See the BOM tab for the full component table.
Custom 3.7V Li-Ion Thin Cell + PMIC (BQ25157) (BQ25157YFPR)
The candidate BQ25157YFPR matches the primary MPN BQ25157 and is manufactured by Texas Instruments.
Espressif ESP32-S3-MINI-1 (ESP32-S3-MINI-1-N4R2)
Candidate 1 (ESP32-S3-MINI-1-N4R2) matches the primary MPN prefix, correct manufacturer, and includes PSRAM (R2) suitabl
Espressif ESP32-S3-MINI-1 (ESP32-S3-MINI-1-N4R2)
Both candidates match the primary MPN prefix and manufacturer, but Candidate 1 (ESP32-S3-MINI-1-N4R2) provides a complet
Miniature Periscope 5X Optical Zoom Module (OV64B + LC898212AXD) (LC898212AXD)
Rejected weak/wrong-class catalog hits; using web recommendation: LC898212AXD
Temple-Concealed Li-Ion Rechargeable Battery Cell (BQ25157YFPR)
The candidate BQ25157YFPR matches the primary MPN BQ25157 and is manufactured by Texas Instruments.
Build Summary
- Difficulty: Advanced
- Estimated time: 6-8 hours
- Tools required: Antistatic tweezers, Component sorting trays, Micro-file, Digital calipers, Isopropyl alcohol, Precision soldering iron
See the Build tab for the full step-by-step assembly guide.
Evidence and Limitations
- Confirm part parameters, certifications, and compatibility against current manufacturer documents.
- Treat industry compliance without test or certificate evidence as a compliance gap, not an approval.
- See Reference Images for visual artifacts and Build Guide for detailed assembly and bring-up steps.