Texas Instruments TPS23755 | Demoboard TIDA-010034

Description

Power over Ethernet (PoE) enables power to be delivered over the same ethernet cable as data with no danger of cross-talk, interference, or corruption of the data streams. This reference design showcases end-to-end power tree for an IP network camera powered using PoE or 12-V adapter based on the TI’s DaVinci™ Digital Media Processor or different application processor. The power tree also derives rails required for different peripherals of an IP network camera like: Image sensor, motor control, Ethernet PHY, RS485 interface, IR LED illumination, audio, motion sensing and the alarm interface.

Features

• TPS23755 IEEE802.3at PoE PD with no-opto flyback DC-DC controller
  • Complete IEEE802.3at PD solution for type-1 PoE
  • Integrated flyback controller with primary side regulation (PSR), frequency dithering and advanced startup
  • 12-V output, 89% efficiency of the PoE-powered flyback power stage
  • Secondary side adapter priority control with smooth transition
• No diode ORing: 88% less power dissipation in adapter input path with TPS2121 power MUX for secondary side ORing
• Two power tree implementations:
  • For high efficiency: 12-V to PoL, using mid input range buck converters
  • For low cost: 12-V to 5-V to PoL, using low input range buck converters
• Both power trees use buck converters with FPWM mode enabling:
  • Fast transient response for handling dynamic load switching on rails suppling power to MPU core and DDR RAM
  • Low output voltage ripple on voltage rails with tighter tolerances like MPU core and DDR RAM

More information

• Datasheet
• IC product information