Class 6, PoE PD Active Clamp Forward Converter(24 V, 2.5 A) Reference Design

Description

This reference design implements a Power over Ethernet (PoE) power device (PD) active clamp forward converter with 24-V and 2.5-A output. A TPS23730 PD with integrated pulse width modulator (PWM) controller provides all the necessary functions to implement the PoE PD control and the PWM control for the active clamp forward converter. This design uses secondary-side regulation (SSR) with an optocoupler feedback.

Features

IEEE802.3bt Type 3 compliant PoE PD
Integrated PWM controller for flyback or active clamp forward configuration
Frequency dithering for EMI reduction
Soft-start control with advanced start-up and hiccup mode overload protection
Soft-stop shutdown
Optional adapter input

Applications

Top Photo

Bottom Photo

1 Test Prerequisites

1.1 Voltage and Current Requirements

Table 1-1 lists the voltage and current requirements.

Table 1-1 Voltage and Current Requirements

Parameter	Specifications
Input voltage	37 V–57 V (48-V nominal)
Output voltage	24 V
Output current	2.5 A (2.1 A with PoE, > 2.1 A with adapter)
Nominal switching frequency	250 kHz