Date：2019-05-16 Categories：Industry News Hits：286
STM's new chipset enables users to quickly develop reliable and space efficient power consumption devices (PD) using the latest Poe specification IEEE 802.3bt.
Pm8804 and pm8805 can be used in Poe converter circuit of electrical equipment, supporting 8-level Poe equipment with power level up to 71w. The new chipset can save circuit board space, enhance product reliability and shorten time to market. It is suitable for the next generation of communication connection equipment, including 5g "small cell", WLAN access point, switch and router. The target applications of the new Poe chipset of STM also include intelligent buildings and intelligent office equipment, such as IP cameras, access control systems, display panels, lamps, electric curtain or shutter controller, video call system, IP phone and desktop console.
The pm8804 enables a fully functional PWM controller for 48V isolated flyback or forward converters and a dual low side gate driver for efficient active clamp forward converter topologies. The operating frequency is optional, up to 1MHz. Small external filters and decoupling components can be used in high power density applications. The pm8804 also has a 20 mA output high voltage start regulator, which helps save circuit board space and bill of materials.
The pm8805 chip includes two active bridges, one charge pump for driving high side MOSFET, one hot swap FET and IEEE 802.3bt standard interface. The integrated active bridge can save the space occupied by 8 discrete MOSFETs and their driving circuits. The pm8805 generates a power ready signal that enables the pm8804 and other circuits (e.g., LED drivers) and supports maintenance of power signature (MPS) current control, allowing the consumer to enter a power saving standby state without disconnecting.
Both products have been put into mass production. Pm8804 is packaged in vfqfpn-16 with 3mm x 3mm and 0.5mm spacing. Pm8805 is packaged with 8mm x 8mm heat dissipation enhanced vfqfpn-43 with bare pad.