M0189 I2C 8x8 ToF Module
A compact multizone Time-of-Flight rangefinder built around the STMicroelectronics VL53L8CX, assembled in the USA by ModalAI. The module provides up to 8x8 (64-zone) depth measurement over an I2C interface and connects to the M0188 or M0195 carrier on the VOXL 2 Mini.
Table of contents
- Description
- Specification
- Functional Description
- Current / Power Consumption
- Requirements
- Technical Drawings
- Software Integration
Description
The M0189 is an I2C 8x8 Time-of-Flight (ToF) rangefinder module assembled in the USA by ModalAI. It is based on the STMicroelectronics VL53L8CX, a direct-ToF, multizone ranging sensor using FlightSense technology and an eye-safe 940 nm Class 1 VCSEL emitter. The module provides absolute distance measurement that is independent of target color and reflectance.
Each M0189 connects to a single ToF port on the M0188 or M0195 carrier (J01, J23, J45, or J67) via an MCBL-00128 cable. The board is hardware-strapped for I2C operation, so only power, ground, and the I2C bus are routed through the connector — no host configuration of the sensor’s mode pins is required. The module is managed in software by voxl-mini-tof-server.
Specification
| Parameter | M0189 I2C 8x8 ToF (Rev A) |
|---|---|
| ModalAI part number | M0189 |
| Sensor | STMicroelectronics VL53L8CX |
| Ranging technology | Direct Time-of-Flight (FlightSense), histogram-based |
| Emitter | 940 nm invisible-light VCSEL, Class 1 eye-safe |
| Multizone resolution | 8x8 (64 zones) or 4x4 (16 zones), software-selectable |
| Field of view | 65° diagonal square FoV (DOE on Tx and Rx) |
| Max ranging distance | Up to 400 cm (target- and ambient-dependent) |
| Max frame rate | 15 Hz @ 8x8 · 60 Hz @ 4x4 |
| Host interface | I2C, up to 1 MHz (board strapped to I2C mode) |
| Default I2C address | 0x52 (8-bit) / 0x29 (7-bit) |
| Supply rails | 3.3 V (AVDD) and 1.8 V (IOVDD / CORE_1V8) |
| Board connector | JST BM05B-SRSS-TBT — SR series, 1.0 mm pitch, 5-position, top-entry |
| Mating cable | MCBL-00128 |
| Connects to | M0188 or M0195 carrier — J01 / J23 / J45 / J67 |
| ESD protection | TVS diodes on supply and I2C lines (D1–D4) |
| Origin | Assembled in the USA |
The VL53L8CX defaults to 4x4 resolution at power-on. Use the ST ULD API (
vl53l8cx_set_resolution()) to switch to 8x8 before setting the ranging frequency, since the maximum frame rate depends on the selected resolution.
Functional Description
The M0189 carries the VL53L8CX (U1) plus its required passives, decoupling, and ESD protection. Only the 1.8 V supply, 3.3 V supply, ground, and the I2C bus are exposed at the board connector. All sensor mode-select pins are tied off on the board so the device powers up in a known, ready-to-range I2C configuration.
On-Board Pin Strapping
The VL53L8CX control pins are configured on the M0189 so the host only needs power and the I2C bus:
| Sensor pin | Strap | Effect |
|---|---|---|
| SPI_I2C_N | Pulled to GND via R4 (47 kΩ) | Selects I2C communication mode |
| LPN | Pulled to 1.8 V via R1 (10 kΩ) | Low-power / comms enable held active |
| NCS | Pulled to 3.3 V via R3 (47 kΩ) | Chip-select inactive (not used in I2C mode) |
| SYNC | Pulled to 1.8 V via R2 (47 kΩ), broken out to TP5 | Available for external synchronization |
| INT | Broken out to TP6 | Data-ready interrupt test point |
I2C bus pull-ups for SCL/SDA are located on the M0188 carrier, not on the M0189 itself.
Current / Power Consumption
| Supply rail | Connector pin | Sensor pins | Max current (design) |
|---|---|---|---|
| 1.8 V (VREG_1P8) | J1.1 | IOVDD, CORE_1V8 | 90 mA max |
| 3.3 V (VREG_3P3) | J1.2 | AVDD | 60 mA max |
Values are the maximum expected currents the module is designed to draw, per the Rev A schematic. Actual consumption varies with resolution, ranging frequency, and integration time.
Requirements
Hardware
- VOXL 2 Mini with an M0188 or M0195
- MCBL-00128 cable to
J01 / J23 / J45 / J67 - 1.8 V and 3.3 V supplied by the carrier
Software
- voxl-mini-tof-server for capture and publishing
- ST VL53L8CX ULD API (STSW-IMG040) for low-level control
- Data available through Modal Pipe Architecture (MPA) and VOXL Portal
Technical Drawings
Step File
Pin-out at J1
The board connector is a JST BM05B-SRSS-TBT (SR series, 1.0 mm pitch, 5-position, top-entry). Pin 1 is the 1.8 V supply; the two mechanical solder tabs (S1, S2) are tied to ground.
| Pin | Signal | Description |
|---|---|---|
| 1 | VREG_1P8 | 1.8 V supply — feeds IOVDD and CORE_1V8 |
| 2 | VREG_3P3 | 3.3 V supply — feeds AVDD |
| 3 | I2C_SCL | I2C clock (pull-up on M0188/M0195) |
| 4 | I2C_SDA | I2C data (pull-up on M0188/M0195) |
| 5 | DGND | Digital ground |
| S1, S2 | DGND | Connector mechanical / shield tabs, tied to ground |
Software Integration
On a configured VOXL 2 Mini, the module is driven by voxl-mini-tof-server, which publishes per-zone depth data into Modal Pipe Architecture for downstream consumers such as VOXL Vision Hub, the mapper, and VOXL Portal.
- Set resolution to 8x8 before configuring the ranging frequency.
- Default I2C address is
0x29(7-bit); change it withvl53l8cx_set_i2c_address()when running multiple modules on one bus. - The
LPNpin can be used to enumerate multiple sensors on a shared bus — note that on M0189 it is held active by R1.
Histogram crosstalk immunity holds beyond ~60 cm. With a cover glass, targets closer than 60 cm may require crosstalk calibration to avoid false-near readings.