STHS4257A

STHS4257A, STHS4257A1 STHS4257L, STHS4257L1 IEEE 802.3af PoE Powered Device (PD) interface controller with integrated signature resistor www.datasheet4u.com Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ IEEE 802.3af-compliant interface for Powered Devices (PDs) Integrated 100V, 450mA power MOSFET low side switch Inrush current limit Normal operation current limit Integrated 25kΩ signature resistor Signature disable (STHS4257A1/L1) Resistor-programmable classification current (Class 0-4) Power Good output, open drain Undervoltage Lockout (UVLO) Thermal overload protection (two-step for the STHS4257A/L) Latch (L) or auto-retry (A) after repetitive thermal overload Industrial temperature range: –40 to +85°C SO8 and DFN8 (3mm x 3mm) packages RoHS compliant 8 1 SO8 (M) DFN8 3mm x 3mm (DB) Applications ■ ■ ■ Voice over IP (VoIP) phones Table 1. Device options Signature disable Order code s b O STHS4257A t e ol o r eP ✔ ) s t( c du 39.2 36.0 39.2 30.5 30.5 30.5 30.5 -O ■ ■ ■ l o bs Web cameras WLAN access points Internet appliances POS terminals RFID readers P e et c u d o r ) s t( UVLO threshold, rising (V) UVLO threshold, falling (V) Protection mode Thermal overload protection 2 steps 1 step 2 steps 1 step Inrush current limit (mA, typ) Normal operation current limit (mA, typ) Auto Auto Latch Latch 350/188 (1) 140 350/188 (1) 140 375 375 STHS4257A1 STHS4257L STHS4257L1 ✔ 36.0 1. Current limit is common for both modes and gets reduced only in case of therm...