Ublox ZED-F9K User Manual

ZED-F9K-Integration manual
Figure 46: VCC pads
4.9 Design guidance
4.9.1 General considerations
Check power supply requirements and schematic:
• Is the power supply voltage within the specified range and noise-free?
• If USB is not used, connect the V_USB pin to ground.
• It is recommended to have a separate LDO for V_USB that is enabled by the module VCC. This is
to comply with the USB self-powered specification.
• If USB is used, is there a 1 uF capacitor right near the V_USB pin? This is just for the V_USB pin.
• Is there a 1 uF cap right next to the module VCC pin?
• Compare the peak current consumption of the ZED-F9K GNSS module with the specification of
your power supply.
• GNSS receivers require a stable power supply. Avoid series resistance (less than 0.2 Ω) in
your power supply line (the line to VCC) to minimize the voltage ripple on VCC. See the ZED-
F9K Power supply section in the Design chapter for more information on the power supply
requirements.
• Allow all I/O to Float/High impedance (High-Z) when VCC is not applied.
4.9.2 Backup battery
Check backup supply requirements and schematic:
• For achieving a minimal time to first fix (TTFF) after a power down (warm starts, hot starts),
make sure to connect a backup battery to V_BCKP.
• Verify your battery backup supply can provide the battery backup current specified in the ZED-
F9K data sheet.
• Allow all I/O including UART and other interfaces to Float/High impedance in HW backup mode
(battery backup connected with VCC removed).
4.9.3 RF front-end circuit options
It is important that the RF input is fed by an active antenna meeting the requirements for
the ZED-F9K.
The first stages of the signal processing chain are crucial to the overall receiver performance.
When an RF input connector is employed this can provide a conduction path for harmful or
destructive electrical signals. If this is a likely factor the RF input should be protected accordingly.
UBX-20046189 - R01
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4 Design Page 88 of 105
C1-Public Early production information

Ublox ZED-F9K Specifications

General

Brand	Ublox
Model	ZED-F9K
Category	Control Unit
Language	English

Summary

System Description

Overview

Introduces the ZED-F9K module, its capabilities, and applications in automotive markets.

Automotive Dead Reckoning (ADR)

Explains ADR technology for high-accuracy positioning in areas with poor or no GNSS coverage.

Priority Navigation Mode

Describes low-latency position output using sensor data for time-critical applications.

Receiver Functionality

Receiver Configuration

Details the configuration of the ZED-F9K using UBX configuration interface keys.

RTCM Corrections

Details the RTCM binary data protocol for GNSS correction information.

Navigation Configuration

Covers configuration options for the navigation engine, including platform settings.

Automotive Dead Reckoning (ADR)

Introduces ADR for high-accuracy positioning in poor/no GNSS coverage areas.

IMU-Mount Alignment

Details configuring IMU-mount misalignment angles for accurate sensor fusion.

Communication Interfaces

Describes the multi-protocol communication interfaces: UART, SPI, I2C, USB.

Antenna Supervisor

Details the antenna supervisor for checking antenna circuits and detecting faults.

Clocks and Time

Introduces concepts of receiver clocks, time bases, and timestamps.

Security

Covers the security concept for the receiver and air interface.

Design

Pin Assignment

Details the pin assignments of the ZED-F9K module and their functions.

Power Supply

Covers the module's power supply requirements and voltage considerations.

Antenna

Discusses requirements for active antennas for good performance.

EOS/ESD Precautions

Covers precautions for Electrostatic Discharge and Electrical Overstress.

Layout

Details layout and placement requirements for optimal GNSS performance.

Design Guidance

Provides general design guidance and checks for successful integration.

Antenna/RF Input

Checks RF input requirements and schematic considerations.

Product Handling

ESD Handling Precautions

Details precautions for handling Electrostatic Sensitive Devices.

Soldering

Covers soldering paste, reflow soldering, rework, and conformal coating.

Appendix

A Glossary

Provides a list of abbreviations and their definitions used in the manual.

C RTK Configuration Procedures with u-center

Guides on evaluating ZED-F9K RTK operation using u-center software.