STHS4257A STMICROELECTRONICS [STMicroelectronics], STHS4257A Datasheet
STHS4257A
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STHS4257A Summary of contents
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... Inrush current limit ■ Normal operation current limit ■ Integrated 25k 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) ■ ...
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Contents 1 Summary description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of tables Table 1. Device options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Figure 2. Pin connections (STHS4257A/L, top view Figure 3. Pin connections (STHS4257A1/L1, top view Figure 4. Application circuit overview Figure 5. Block diagram (STHS4257A/L Figure 6. Typical application circuit (STHS4257A/L) with a DC/DC converter Figure 7. Block diagram (STHS4257A1/L1 Figure 8. Typical application circuit (STHS4257A1/L1) with a DC/DC converter Figure 9. SO8 – ...
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... STHS4257A1/L1 to interface with legacy Power over Ethernet (LAN) systems while maintaining compatibility with the current IEEE 802.3af specification. Each of the two basic part types, the STHS4257A/L and the STHS4257A1/L1, is available either with Latched Operation (L) Mode or with Automatic Retry (A) Mode after fault conditions ...
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... Figure 1. Logic diagram SIGDISA R CLASS 1. STHS4257A1 and STHS4257L1 devices only. Table 2. Signal names Pin STHS4257A/L STHS4257A1/ — Figure 2. Pin connections (STHS4257A/L, top view) Figure 3. Pin connections (STHS4257A1/L1, top view) 6/18 GND (1) STHS4257A/L STHS4257A1/ AI12214a ...
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... Signature disable input (SIGDISA) This pin is internally pulled down unused. Tie to GND to present an invalid signature. Note: This signal is available for STHS4257A1 and STHS4257L1 only. 1.1.5 Power Good output (PWRGD) This pin indicates that the STHS4257x/x1 power MOSFET is fully on and works in normal operation mode (Power Good). Open drain, low impedance means that the power is good ...
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... Data to Ethernet Physical Layer Device Pair 2x DF01S Spare Pair Spare Pair RX Data to Ethernet Physical Layer Device Pair 1. STHS4257A1 and STHS4257L1 devices only. To disable signature, tie this pin to GND. 2. This configuration uses either data wires or spare wires for DC power. 8/18 GND SMAJ58A SIGDISA (1) PWRGD STHS4257A/L C1 STHS4257A1/L1 0.1µ ...
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... Figure 5. Block diagram (STHS4257A/ ref 2 R CLASS 3 NC Control Circuits ref Figure 6. Typical application circuit (STHS4257A/L) with a DC/DC converter ~ + C1 48V from Diode power sourcing Bridge 0.1µF equipment (PSE) 100V ~ – DF01S Classification Current Source + 25k – EN Signature Resistor Power Good ...
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... Figure 7. Block diagram (STHS4257A1/L1 CLASS Ref LIMIT HIGH 2. Ref LIMIT LOW Figure 8. Typical application circuit (STHS4257A1/L1) with a DC/DC converter 48V from power sourcing equipment (PSE) 10/18 Classification Current Load ref + – EN Signature Resistor Power Good Control Circuits ...
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Absolute maximum ratings Stressing the device above the rating listed in the cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicated in the ...
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... Electrical parameters Over the full operating temperature range, unless otherwise noted. Specifications common for both STHS4257x (=STHS4257A, STHS4257L) and STHS4257x1 (=STHS4257A1, STHS4257L1) product families unless otherwise noted. Table 5. Electrical parameters Symbol Parameter Maximum Operating Voltage Signature Range Classification Range UVLO Turn-On Voltage, ...
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Table 5. Electrical parameters (continued) Symbol Parameter Input Current Limit, Low Level, STHS4257x1 I LIMIT LOW (inrush mode) I Input Current Limit, STHS4257x V LIMIT Overtemperature Input Current I LIMIT WARM Limit, STHS4257x Overtemperature Trip T OVERTEMP Temperature, STHS4257x Thermal ...
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Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK packages. These packages have a Lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner ...
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Figure 10. DFN8 – 8-lead dual flat no-lead outline, package mechanical drawing Seating Plane C 1. Drawing is not to scale. Table 7. DFN8 – 8-lead dual flat no-lead outline, package mechanical data mm Symb Typ Min A 0.90 0.80 ...
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Part numbering Table 8. Ordering information scheme Example: Device type STHS Product options 4257A 4257A1 4257L 4257L1 Package M = SO8 (150mils width) ( DFN8 (3mm x 3mm) Temperature range 6 = –40 to 85°C Shipping method ...
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Revision history Table 9. Document revision history Date Revision 12-Jul-2006 19-Dec-2006 24-May-2007 26-Jul-2007 1 Initial release. 2 Updated Features and Table 3 Formatting changes and updatedTable Document status upgraded to full datasheet, updated cover page 4 and Table 8. ...
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Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any ...