Preface
The charging head network got the PoE injector of the Cisco 8832 conference phone, which has an RJ45 wired network port and a USB-C power supply port on one side, and a single USB-C port on the other side for connecting to the phone. By using an injector, the conference phone can be powered and connected to a wired network at the same time via the USB-C interface.
This PoE injector has a gray plastic shell with USB-C ports at both ends, and a label is printed next to the interface to identify the interface function, which is easy to install and use. The following charging head network will bring the disassembly of Cisco's PoE injector, and take a look at the internal materials and workmanship.
思科USB-C+RJ45 PoE注入器外观
Like the previously disassembled Cisco USB-C power adapter, this 2-in-1 converter also uses the same material and color matching shell, and the surface of the body is frosted to effectively resist fingerprints.
The center of the top surface of the fuselage is designed with the CISCO brand.
There is a product-related information sticker at the bottom, and it can be seen that the product has passed UL and FCC certification.
One end of the fuselage is equipped with a USB-C power supply port and an RJ45 network port.
The other end is equipped with a USB-C port, and the output from this end is to supply power to the device and the network.
The measured product body length is 78.25mm.
The width is 54.82mm.
The thickness is 26.89mm.
The size of the product in the hand is intuitively felt.
In addition, its net weight was measured to be about 80g.
思科USB-C+RJ45 PoE注入器拆解
After looking at the appearance of Cisco's PoE injector, let's start disassembling it and take a look at the internal materials and design.
The injector housing is disassembled along the seams on both sides of the housing, and the housing is ultrasonically welded.
The internal PCBA module is fixed by screws.
Close-up of Phillips set screws.
Unscrew the fixing screws to separate the upper PCBA module.
There is also a layer of PCBA modules at the bottom.
Close-up of the studs fixing the underlying PCBA module.
Unscrew the fixing studs and take out the bottom PCBA module.
The bottom PCBA module welds the power supply transformer, the network isolation transformer, the rectifier bridge and the network cable socket and the control chip.
The back of the PCBA module is soldered with filter capacitors, SMD optocouplers and connector sockets.
The network cable interface adopts a plastic shell and is patch welded.
There are eight pins inside the interface.
Close-up of a network isolation transformer.
Two TVS arrays are used for surge protection at the network cable interface.
Close-up of the connector connecting the two-layer PCBA module.
Close-up of four filter inductors.
One chip from Maxim, model MAX5983AE, for hot-swap control.
Close-up of the transformer used with it.
Close-up of the rectifier bridge of two silk-screened MB2S.
A screen-printed NG TVS diode is used for overvoltage protection.
One filter capacitor is 22μF 6.3V.
Close-up of a silkscreened 332NL inductor.
A controller is silk-screened with AIR BAN.
A switch tube silk screen printing 244.
Two 250mΩ resistors are used to sense the current.
The other switch tube is of the same type.
The transformer used for power supply is from Sumida with a copper foil shield around the core.
The other PCB is soldered with two USB-C sockets, two USB-C interface controllers, USB to Gigabit Ethernet controllers and filter capacitors, etc.
There are no soldering elements on the back of the small plate.
The bridge chip from Infineon, model CYUSB3610, is a USB3.0 to Gigabit Ethernet converter with integrated USB3.0 physical layer and controller, support for energy-saving mode, advanced power management and Wake-on-LAN.
25.000MHz时钟晶振特写。
Close-up of two SMD LEDs.
Memory from STMicroelectronics, model 93C66WP.
The USB-C interface controller from Infineon's EZ-PD CCG3 family, model CYPD3125-40LQXI, is a complete USB-C and USB-PD interface control solution for notebook, monitor, docking station and adapter applications.
A total of two USB-C ports are used, corresponding to two USB-C ports.
Close-up of the external bleeder resistor on the chip.
A silk-screened ADO chip.
One VBUS switch tube is silk-screened with BH4AC.
A 5mΩ sense resistor is used to sense the output current.
A VBUS switch from Infineon, model BSZ0907ND, dual NMOS, withstand voltage 30V, conduction resistance of 9.5 mΩ and 7.2 mΩ respectively, is a series half-bridge connection.
合金电感来自Colicraft。
Close-up of three MLCC capacitors connected in parallel.
The synchronous step-down converter is a synchronous step-down converter with 17V input voltage and 500mA output current from Texas Instruments, silkscreen QUE, model TPS62170, and an integrated switch inside the chip.
Close-up of 2.2μH buck inductor.
Close-up of another buck converter to power the Ethernet bridge chip.
Close-up of five MLCC filter capacitors connected in parallel.
The USB cable is equipped with a filter inductor.
A chip is silk-screened AATB.
Three VBUS switch tubes silk-screened BH4AC.
Close-up of the connector connected to the bottom PCB.
The USB-C receptacle is fixed by through-hole welding, and the black rubber core is clamped with steel sheet to increase the strength.
The USB-C connector on the other end has the same design.
Close-up of the reserved connector inside the housing.
The other connector looks the same.
A list of all dismantling and a family photo.
Summary of the dismantling of the charging head network
Cisco's PoE injector is rugged and durable in a gray plastic housing. One of them is equipped with RJ45 wired network interface and USB-C power supply interface, and the other side is equipped with USB-C interface, and the two interfaces have logos respectively to indicate the connected devices. By using an injector, power and wired network connectivity can be achieved via the phone's built-in USB-C port.
Through the dismantling of the charging head network, it is learned that this injector is composed of two PCBA modules, one of which is equipped with a power supply conversion chip and a network transformer, and the other PCBA is equipped with a network bridge chip and a PD control chip. The controller for the two USB-C interfaces is from Infineon with model number CYPD3125, and the bridge chip is also from Infineon with model number CYUSB3610. The internal materials of this injector are all first-line brands, and the workmanship is solid and reliable.