FNIRSI FNB38 USB Tester – High Precision Color Screen Voltmeter Ammeter & Fast Charge Protocol Trigger

Overview

The FNIRSI FNB38 is a multi-function, high-precision USB power monitor designed for testing chargers, power banks, and USB cables. Despite its compact size, it features a 1.44-inch high-definition colour LCD and provides laboratory-grade measurements. It is widely used by hobbyists and repair technicians to verify fast-charging standards and troubleshoot power-related issues in smartphones, laptops, and DIY electronics.

Key Features

• 6-Digit Precision: Displays voltage, current, and power with five decimal places ($0.00001$ resolution) for extreme accuracy.

• Protocol Detection: Automatically identifies fast-charging protocols including QC 2.0/3.0, Huawei FCP/SCP, and Samsung AFC.

• Multi-Interface Support: Includes USB-A (Male/Female), USB-C (Input), and Micro-USB ports to test a wide variety of devices.

• Offline Data Recording: Can record energy and capacity data ($mAh/Wh$) for battery health analysis without being connected to a PC.

• Screen Flip: The user interface can be rotated 180 degrees, allowing you to read the data comfortably regardless of the charger’s orientation.

Technical Specifications