LTC4259CGW Linear Technology, LTC4259CGW Datasheet - Page 30

• Manufacturer Part Number: LTC4259CGW
• Manufacturer: Linear Technology

Specifications of LTC4259CGW

• Linear Misc Type: Negative Voltage
• Operating Supply Voltage (typ): -48V
• Operating Supply Voltage (max): -57V
• Operating Temperature (min): 0C
• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 36
• Lead Free Status / Rohs Status: Not Compliant

APPLICATIO S I FOR ATIO
LTC4259
data lines. Also a single-stage RC lowpass filter (shown in
Figure 20) will attenuate out-of-band noise. There won’t be
much voltage drop across the RC filter because the imped-
ance of the OSCIN pin is high, typically 500k.
CONCLUSION
The LTC4259 provides the precision analog circuitry and
logic necessary to build IEEE 803.3af compliant Power
over Ethernet power sourcing equipment (PSE). The
requirements placed on the PSE are complex and the
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U
W
U
LTC4259 handles most of them but there are elements of
the PSE that are beyond the LTC4259’s control.
These potential compliance pitfalls can be avoided during
circuit design and layout by paying attention to the issues
mentioned above. In addition, consider checking for IEEE
802.3af compliance after subjecting the PSE to real-world
fault conditions: ESD and cable discharge events, shorted
ports, connecting to an already powered port, power
supply glitches and so on. Linear Technology’s Applica-
tions department can also provide additional support.
4259i