Epson IMU G Series - User Manual

Need help?

Do you have a question about the Epson IMU G Series and is the answer not in the manual?

Summary

5. Configuration

5.1. Configuration Resistors

Explains the use of R1 and R2 resistors for optional signal connections to the IMU GPIO2_EXT input.

6.1. OEM7 Development Kit Connector P1

6.2. Epson G Series IMU Connector P2

6.3. Epson V Series IMU Connector P3

The Epson IMU_OEM7 Interposer Board (EIIB) is a specialized evaluation board designed for engineers to interface Epson G-series and V-series IMUs with the NovAtel OEM7 Development Kit. Its primary function is to facilitate prototyping and software development by providing a direct hardware connection between these components, eliminating the need for additional hardware or complex cabling. The EIIB is intended for laboratory and development environments and should not be used as part of a finished end product.

Function Description:

The EIIB acts as a bridge, routing all necessary interface signals between the Epson IMU and the NovAtel OEM7 Development Kit. It mounts directly onto the designated "IMU Board" area of the OEM7 Development Kit. The board supports both Epson G-series IMUs (such as M-G320, M-G354, or M-G364) and Epson V-series IMUs (like the M-V340) through dedicated socket connectors.

Power for the EIIB is supplied directly from the OEM7 Development Kit via 3.3V power supply and GND pins on connector P1. The serial host bus interface between the OEM7 Development Kit and the EIIB exclusively supports an SPI interface with a DRDY (Data Ready) line; a UART interface is not supported.

A key feature of the EIIB is its optional connectivity for OEM7 output signals (TIMEMARK or EVENT_OUT2) to the Epson IMU's GPIO2/EXT input pin. This is achieved through mountable 33 ohm 5% 0603 size resistors (R1 and R2). By default, these resistors are not mounted, allowing users to select which signal, if any, to connect. It is crucial not to mount both R1 and R2 simultaneously, as this would short the TIMEMARK and EVENT_OUT2 signals, potentially damaging the OEM7 Development Kit. If neither TIMEMARK nor EVENT_OUT2 is utilized, these resistors do not need to be mounted. This optional connection requires additional configuration settings on both the OEM7 Development Kit and the Epson IMU.

Important Technical Specifications:

Connectors:
- P1 (OEM7 Development Kit Connector): SMT header 20x2, 1.27 mm pitch (Samtec FTSH-110-01-F-DV). This connector mates with the OEM7 Development Kit. It provides 3.3V power, circuit ground, SPI clock (supports SPI Mode 3 only), SPI chip select (supports SPI Mode 3 only), SPI Master In Slave Out (supports SPI Mode 3 only), SPI Master Out Slave In (supports SPI Mode 3 only), and optionally provides PPS (TIMEMARK) and EVENT_OUT2 clock signals. It also connects to the Epson IMU DRDY output.
- P2 (Epson G Series IMU Connector): SMT socket 20x2, 1 mm pitch (Samtec CLM-110-02-L-D). This connector mates with Epson G-series pin compatible IMUs (M-G320, M-G354, M-G364). It provides SPI clock, SPI MISO, GND, SPI MOSI, SPI nCS, IMU UART TXDO (for internal debug), IMU UART RXDI (for internal debug, pulled to VCC with 10K ohm), 3.3V power, IMU GPIO1 DRDY (connects to OEM7 EVENT_IN2 signal), IMU GPIO2_EXT (optional connection to OEM7 TIMEMARK or EVENT_OUT2), and IMU_nRESET (connected to RC delay network).
- P3 (Epson V Series IMU Connector): SMT socket 20x2, 0.4 mm pitch (Panasonic AXE120224). This connector mates with Epson V-series compatible IMUs (M-V340). It provides similar signal connections to P2, including GND, SPI MOSI, SPI CLK, SPI MISO, SPI nCS, IMU UART TXDO (for internal debug), IMU UART RXDI (for internal debug, pulled to VCC with 10K ohm), IMU GPIO1 DRDY, 3.3V power, IMU GPIO2_EXT, and IMU_nRESET.
Configuration Resistors: Two PCB footprints for 33 ohm 5% 0603 resistors (R1, R2) for optional connection of OEM7 TIMEMARK or EVENT_OUT2 to Epson IMU GPIO2/EXT.
Power Supply: 3.3V, supplied by the OEM7 Development Kit.
Mounting: 3.45 mm diameter mounting holes on the four corners for securing the PCB to the NovAtel OEM7 Development Kit. Two diagonal mounting holes for securing the IMU to the EIIB (for P2, SEMS M2-14 stainless steel screw and M2 stainless steel hex nut are recommended).

Usage Features:

Direct Mounting: The EIIB is designed for direct mounting onto the NovAtel OEM7 Development Kit, simplifying the setup process.
Dual IMU Series Support: The board accommodates both Epson G-series and V-series IMUs through separate, dedicated connectors (P2 and P3), offering flexibility for different IMU models.
Optional Signal Routing: The ability to optionally connect OEM7 TIMEMARK or EVENT_OUT2 signals to the Epson IMU's GPIO2/EXT input provides enhanced synchronization and control capabilities for specific applications.
Clear Orientation Guides: Silk screen markings and mounting hole patterns on the PCB provide clear guidance for correct IMU mounting orientation, minimizing the risk of incorrect installation.
SPI Interface: Supports SPI Mode 3 for communication, which is a common and robust serial interface for sensor data.

Maintenance Features:

Component List: A detailed Bill of Materials (BOM) is provided, listing all components by ID, designator, quantity, part number, manufacturer, and description. This aids in component identification and potential replacement if necessary.
Schematic Diagrams: Comprehensive schematic diagrams are included, illustrating the internal wiring and connections of the EIIB. These diagrams are invaluable for debugging, understanding signal flow, and advanced troubleshooting.
Board Layout Diagrams: PCB front and back side views are provided, showing the physical placement of components and connectors. This helps in visual inspection and locating specific parts.
Revision History: A revision history table tracks changes made to the manual, including dates, pages affected, categories, and descriptions of updates. This ensures users have access to the most current and accurate information.
Safety Notices: Important notices regarding the evaluation board's intended use, safety precautions, and disposal guidelines are clearly stated, promoting safe and responsible handling. For instance, the warning against mounting two IMUs simultaneously on P2 and P3, or mounting both R1 and R2 resistors, is critical for preventing irreversible damage.
Technical Support: Users are advised to contact NovAtel directly for inquiries regarding supported Epson IMU models and additional configuration settings, indicating a clear path for technical assistance.