{"product_id":"usb-tester-4-28v-7a-lcd-usb-a-c-voltage-current-power-tester","title":"USB Tester 4-28V 7A LCD USB A\u0026C Voltage Current Power Tester","description":"\u003cp\u003eIn this review the FNIRSI USB tester is examined for hobbyists, technicians and anyone who frequently tests chargers, cables and power banks; its single biggest reason to buy is its combination of multiport physical connectors with protocol detection and app support, making it a practical troubleshooting tool. The tester offers a clear 2.0' TFT LCD and integrated USB-A, Micro-USB and Type-C ports, and is useful when you need to verify voltage, current, power, capacity and fast charge protocol behavior without carrying multiple adapters.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMulti-port design:\u003c\/strong\u003e Integrated USB-A, Micro-USB and Type-C ports let the tester connect directly to a wide range of chargers and cables without extra adapters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtocol detection:\u003c\/strong\u003e Automatic support for QC2.0\/QC3.0, PD2.0\/3.0, FCP\/SCP, AFC, VOOC\/WARP and Super VOOC triggers makes identifying fast charge behavior straightforward.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccurate measurement:\u003c\/strong\u003e External 16-bit ADC and a PD physical protocol chip provide detailed readings of voltage, current, power and capacity for reliable diagnostics.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWaveform and ripple views:\u003c\/strong\u003e Low-speed waveform drawing and ripple measurement with adjustable sampling rates let users inspect transient behavior and noise on power lines.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApp connectivity:\u003c\/strong\u003e Bluetooth app integration and onboard features such as temperature and PD monitoring allow logging and remote observation from a mobile device.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCable and accessory tests:\u003c\/strong\u003e E-Marker and DASH cable reading plus differential wire resistance measurement make it useful for cable verification and quality checks.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThe FNIRSI USB tester is ideal for electronics hobbyists, field technicians and mobile repairers who need a compact, all-in-one meter to validate chargers, power banks and cable behavior. Its combination of protocol triggering and recording is particularly useful for anyone diagnosing charging faults or confirming fast charge compatibility.\u003c\/p\u003e\n\u003cp\u003eUsers who want the simplest possible plug-and-play experience with printed documentation may be disappointed, since the device relies on digital manuals via QR code and the app. If you only need a basic USB voltage reader without protocol testing or advanced logging, a simpler meter may be a better, lower-cost choice.\u003c\/p\u003e\n\n\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eComprehensive protocol detection that covers PD, QC, VOOC and other fast charge standards for accurate compatibility checks.\u003c\/li\u003e\n\u003cli\u003eIntegrated sockets and clear 2.0' TFT display make field use convenient without extra dongles.\u003c\/li\u003e\n\u003cli\u003eDetailed measurements including capacity, D+\/D- voltage, ripple and waveform drawing support deeper diagnostics.\u003c\/li\u003e\n\u003cli\u003eApp software and firmware update path allow logging and future improvements.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eManual is digital only and not printed, which some users find inconvenient for first-time setup.\u003c\/li\u003e\n\u003cli\u003eDevice complexity means a learning curve for users who only need simple voltage readings.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eDisplay\u003c\/td\u003e\n\u003ctd\u003e2.0' TFT LCD\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput\/Output Ports\u003c\/td\u003e\n\u003ctd\u003eUSB-A, Micro-USB, Type-C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMeasured Parameters\u003c\/td\u003e\n\u003ctd\u003eVoltage, Current, Power, Resistance, Capacity, D+\/D- voltage\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProtocol Support\u003c\/td\u003e\n\u003ctd\u003ePD2.0\/3.0, QC2.0\/3.0, FCP\/SCP, AFC, VOOC\/WARP, Super VOOC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eADC\u003c\/td\u003e\n\u003ctd\u003eExternal 16-bit ADC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSampling Rates\u003c\/td\u003e\n\u003ctd\u003eLow-speed 2 sps-100 sps; ripple up to 4 M sps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAdditional Features\u003c\/td\u003e\n\u003ctd\u003eE-Marker\/DASH reading, temperature measurement, app connectivity\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe FNIRSI USB tester is a versatile, well-built tool for anyone who needs to test charging behavior, cable quality and protocol compatibility; it packs advanced measurement and automatic fast charge detection into a compact unit that offers strong value for technicians and enthusiasts. Those wanting a simple plug-in voltmeter should consider a basic alternative, but for diagnostic depth and protocol support this tester is hard to match at the price.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it detect fast charge protocols automatically?\u003c\/strong\u003e\u003cbr\u003eYes, automatic monitoring supports QC2.0\/QC3.0, PD2.0\/3.0, FCP\/SCP, AFC, VOOC\/WARP and Super VOOC triggers.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan it read cable E-Marker chips?\u003c\/strong\u003e\u003cbr\u003eYes, the tester can read E-Marker and DASH cable data to help verify cable capabilities.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs there a printed manual included?\u003c\/strong\u003e\u003cbr\u003eNo, the device uses a QR code for access to the manual, firmware and app downloads to reduce paper use.\u003c\/p\u003e","brand":"FNIRSI","offers":[{"title":"Default Title","offer_id":48707398959323,"sku":"B0BJ253W31","price":58.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/71VDjC5CdjL._SL1500.jpg?v=1778907292","url":"https:\/\/gearmusthave.com\/products\/usb-tester-4-28v-7a-lcd-usb-a-c-voltage-current-power-tester","provider":"GearMustHave","version":"1.0","type":"link"}