PM8805TR STMicroelectronics

PM8805 IEEE 802.3bt PoE-PD interface with embedded dual active bridge Datasheet - Production data Applications High power wireless data systems Security cameras Access points Public information displays PoE lighting systems VFQFPN43 8x8mm exposed pad Description The PM8805 is a system-in-package for smart power supply of Power over Ethernet (PoE) Powered Devices (PD) and it is applicable for Features power level up to 99.9 W. Dual active bridge, hot swap MOSFETand It embeds: two active bridges and their driving PoE-PD interface in a system-in-package circuitry, a charge pump to drive the high-side 100 V N-ch MOSFETs with 0.2 total path MOSFETs, the hot swap MOSFET and the resistance for each active bridge. interface compliant with IEEE 802.3bt. 100 V, 0.1 high-side N-ch hot swap MOSFET The device performs the physical layer PoE-PD single-signature interface compliant classification, providing the indication of with IEEE 802.3bt / at / af successful PSE type identification. A 4-pair PSE is identified and the information is available by a Supports 4-pair PoE applications dedicated matrix of Tx signals. Supports 12 V auxiliary sources The device works with power either from the Identifies which kind of PSE (standard or Ethernet cable or from an external power source legacy) is connected with and provides such as a wall adapter, with possible prevalence successful IEEE802.3bt / at / af classification of the auxiliary source with respect to the PoE. indication as a combination of the T0, T1 and T2 signals (open drain) The PM8805 is suitable to build the interface section of PoE switch mode power supplies Smart operational modes targeting the highest conversion efficiency. It Programmable classification current with provides a PGD signal that can be used to enable 3.3 ms delay. a PWM controller, a DC-DC converter or an LED Optional Autoclass feature driver. Advanced energy-saving MPS timings Table 1. Device summary Two-step hot swap current protection: DC with 1 ms delay and short-circuit with 10 us delay. Part number Package Packing Controlled pre-charge of the output capacitor VFQFPN PGD signal (open drain) to enable an external PM8805TR 8X8X1.0 43L Tape and reel PWM controller. PITCH 0.5 Thermal shutdown protection April 2019 DS12813 Rev 2 1/48 This is information on a product in full production. www.st.comContents PM8805 Contents 1 Typical application circuit and block diagram 6 1.1 Application circuit 6 1.2 Block diagram . 7 2 Pin description and connection diagram 8 3 Electrical specifications . 12 3.1 Absolute maximum ratings 12 3.2 Recommended operating conditions 13 3.3 Thermal data 14 3.4 Electrical characteristics 15 4 PM8805 overview . 19 4.1 Detection and DET pin . 19 4.2 Boot and reset . 20 4.3 PoE classification . 20 4.4 Autoclass . 24 4.5 Charge pump and VCP pin . 24 4.6 Input Bridges 24 4.7 Hot swap, CTRL and PGD pins 26 4.8 Hot swap protections 28 4.9 Interface with a DC/DC converter . 28 4.10 Auxiliary sources . 29 4.11 Operation modes and STBY, FAUX, RAUX command signals 32 4.12 Type T0, T1, T2 output signals . 33 4.13 Standby and MPS 34 4.14 Special operation modes . 36 5 Thermal aspects . 38 5.1 Power dissipation . 38 5.2 Overtemperature protection . 40 2/48 DS12813 Rev 2