Tech Blog

Imported products have been discontinued, prices have increased, and delivery times are long. How can we make a reliable substitute for domestic Pin-to-Pin? This article provides an in-depth analysis from the turns ratio, OCL under PoE bias, return loss/insertion loss template, isolation withstand voltage and PoE current rating. It also attaches a full range of VOOHU LAN transformers and SYT integrated magnetic RJ45 replacement selection table, five-step verification process and FAQ.

Switch/router board power running hot, ripple too high, ports failing radiated EMC? A practical guide to buck power inductors—ripple current, saturation current Isat, temperature-rise current Irms, DCR and magnetic shielding—with a VOOHU molded-inductor (WHYT1050/1265/2313) selection table, layout checklist and FAQ.

When choosing a network transformer, you only look at speed, packaging, and PoE current, but the prototype repeatedly overturns in negotiation, packet loss, radiated emission, and temperature rise? The problem often lies in the few manual parameters that are skipped. VOOHU explains the five most critical parameters of the network transformer data manual - open-circuit inductance OCL, insertion loss, return loss, common mode rejection ratio CMRR, and DC resistance DCR - one by one: which test bench faults each corresponds to, how to read the numbers, and a quick checklist for selection based on

The network port function and EMC have passed, but it is stuck in the final Hi-Pot voltage test? Starting from the isolation nature of Ethernet transformers, VOOHU dissects the real causes of sparking and excessive leakage current (center tap capacitor withstand voltage, PCB creepage distance, GDT malfunction), and provides a safety selection table for isolation voltage withstand voltage of 1500V~5000V full-range network transformers and integrated magnetic RJ45.

The conduction disturbance (CE) at the power supply end exceeds the standard, but it doesn’t move even after adding a common mode inductor? VOOHU explains the causes from the two noise paths of differential mode and common mode, analyzes the selection logic of peak impedance, DC bias and leakage inductance of common mode inductors, and provides a selection table and three-step rectification method for the on-shelf material numbers of common mode inductors and integrated inductors of power lines.

The PSE port of the PoE switch is not a simple copy and paste of the network port. This article dissects the design points of the PSE side from five dimensions: DC bias magnetism of the network transformer, choice between multi-port integrated magnetic RJ45 and discrete network transformers, crosstalk between ports and Bob Smith termination, three-level surge protection and thermal design, and provides a VOOHU on-rack material number selection table.

Gigabit Ethernet ports on industrial gateways and PLCs often share a cabinet with VFDs and switching supplies, where ground potential differences drive ground loops and common-mode noise couples into the pairs. This guide dissects the physical layer and gives in-stock VOOHU selection answers.

10/100BASE-TX ports are high-volume, cost-sensitive and exposed, and often fail on ESD, lightning surge and EMC. This guide explains the LAN transformer's role and key parameters from the 100BASE-TX physical layer, how ESD/surge damages the PHY, and maps VOOHU's in-stock 10/100 transformers, integrated magnetic RJ45 and GDT+TVS+ESD three-stage protection to a selection table.

Consumer-grade products such as home routers, desktop switches, set-top boxes (STB), optical modems (ONU) and smart-speaker ports share two labels: high volume and cost sensitivity. On a home router shipping in the millions, saving a few cents of port BOM

A gigabit Ethernet port (1000BASE-T) is a near-mandatory feature on almost every switch, router, IP camera (IPC) and industrial gateway board — and it is also one of the interfaces most likely to bite back during bring-up. In the field, engineers ke

Why do IP-camera Ethernet ports drop offline and blow dead every storm season? VOOHU breaks down the three jobs of the RJ45 port—LAN-transformer isolation & PoE current rating, PoE power-transformer sizing for 802.3af/at/bt, and coordinated GDT/TVS/ESD surge protection—with a real part-number selection table for reliable outdoor ports.

From the center tap, Bob Smith terminal to PCB layout, the system sorts out the most common pitfalls of the Ethernet port, and provides selection suggestions based on VOOHU full-rate network transformers and supporting components.