TPS23753

Part: TPS23753APWR — Texas Instruments

Type: IEEE 802.3at PoE PD Interface with Isolated Current-Mode DC/DC Controller

Description: IEEE 802.3at type 1 (13 W) PoE PD interface with a 100 V, 0.7 Ω typical hotswap MOSFET and a current-mode dc/dc controller with programmable frequency (248 kHz typical at RFRS = 60.4 kΩ) and up to 80% duty cycle, in a TSSOP-14 package.

Operating Conditions:

• Supply voltage: VDD, VDD1 to RTN 0–57 V; VC to RTN 0–18 V
• Operating junction temperature: -40 to 125 °C
• RTN current: up to 350 mA (TJ ≤ 125 °C)
• Synchronization pulse width: 25–150 ns

Absolute Maximum Ratings:

• VDD, VDD1, DEN, RTN: -0.3 to 100 V
• VDD1 to RTN: -0.3 to 100 V
• VC to RTN: -0.3 to 19 V
• CLS: -0.3 to 6.5 V
• GATE to RTN: -0.3 to VC + 0.3 V
• GATE average current: 25 mA RMS
• ESD: HBM 2 kV, CDM 500 V, system level (contact/air) 8/15 kV
• Operating junction temperature: -40 °C to internally limited

Key Specs:

• PoE UVLO: 35 V typ rising (33.9–36.1 V), hysteresis 4.55 V typ
• Hotswap MOSFET on-resistance: 0.7 Ω typ, 1.2 Ω max
• Hotswap current limit: 405–505 mA; inrush limit 100–180 mA
• Detection current: 64.3 μA typ at VDD = 1.6 V; 406 μA typ at VDD = 10 V
• Classification current: 2.14 mA (RCLS = 1270 Ω) to 39.9 mA (RCLS = 63.4 Ω) typ
• VC UVLO: 9 V typ rising, 3.5 V hysteresis; operating current 0.58 mA typ (VC = 12 V)
• Switching frequency: 223–273 kHz (RFRS = 60.4 kΩ); max duty cycle 76–81%
• VB bias rail: 4.75–5.25 V; CS threshold VCSMAX 0.50–0.60 V
• GATE drive: 0.46 A source, 0.79 A sink typ
• Thermal shutdown: 145 °C typ, 20 °C hysteresis

Features:

• Optimized for isolated converters
• Complete PoE interface with single-resistor classification
• Adapter ORing support (highest voltage, adapter preference, or PoE preference) and 12 V adapter support
• Programmable frequency with external synchronization
• Bootstrap startup with internal switched current source
• Programmable blanking, internal slope compensation
• 15 kV / 8 kV system-level ESD capable
• Thermal shutdown

Applications:

• IEEE 802.3at compliant powered devices
• VoIP telephones
• Access points
• Security cameras

Package:

• PW (TSSOP-14), marking TP23753

• Optimized for Isolated Converters
• Complete PoE Interface
• Adapter ORing Support
• 12 V Adapter Support
• Programmable Frequency with Synch.
• Robust 100 V, 0.7 Ω Hotswap MOSFET
• Small TSSOP 14 Package
• 15 kV / 8 kV System Level ESD Capable
• -40°C to 125°C Junction Temperature Range
• Design Procedure Application Note - SLVA305
• Adapter ORing Application Note - SLVA306

• IEEE 802.3at Compliant Powered Devices
• VoIP Telephones
• Access Points
• Security Cameras

1

This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.

ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.

Refer to Figure 1 for component reference designators ® CS for example ), and the Electrical Characteristics table for values denoted by reference (VCSMAX for example). Electrical Characteristic values take precedence over any numerical values used in the following sections.

Unless otherwise noted: CS = APD = CTL = RTN, GATE open, RFRS = 60.4 k Ω , RBLNK = 249 k Ω , CVB = CVC = 0.1 μ F, RDEN = 24.9 k Ω , RCLS open, VVDD-VSS = 48 V, VVDD1-RTN = 48 V, 8.5 V ≤ VVC-RTN ≤ 18 V, -40°C ≤ TJ ≤ 125°C

Voltages are with respect to VSS (unless otherwise noted)

Voltage with respect to VSS (unless otherwise noted)

Sources of nearby local PCB heating should be considered during the thermal design. Typical calculations assume that the TPS23753 is the only heat source contributing to the PCB temperature rise. It is possible for a normally operating TPS23753 device to experience an OTSD event if it is excessively heated by a nearby device.