Intel® LXT9785 and Intel® LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers Datasheet
The Intel LXT9785 and LXT9785E are 8‑port Fast Ethernet PHY transceivers that support IEEE 802.3 physical‑layer applications at 10 Mbps and 100 Mbps. Each port can operate over twisted‑pair (10BASE‑T, 100BASE‑TX) or LVPECL for 100BASE‑FX fiber, and the devices include auto‑MDI/MDIX and optional DTE detection for IP‑telephony power delivery. The transceivers run from a single 2.5 V supply and consume about 250 mW per port.
The datasheet provides a block diagram, pin and ball assignments for PQFP and BGA packages, functional descriptions, electrical specifications, timing diagrams, power and clock requirements, auto‑negotiation behavior, cable‑diagnostics procedures, design recommendations, and ordering information for various package formats.
| Number of ports | 8 |
|---|---|
| Supported data rates | 10 Mbps and 100 Mbps |
| Interface types per port | Twisted‑pair (10BASE‑T, 100BASE‑TX) and LVPECL (100BASE‑FX) |
| Supply voltage | 2.5 V |
| Power consumption per port | 250 mW typical |
| Operating temperature range | -40 °C to +85 °C (LXT9785HE) |
| Auto MDI/MDIX | Supported |
| DTE detection (IP‑telephony) | LXT9785E only |
Each port can be configured for twisted‑pair (10BASE‑T, 100BASE‑TX) or LVPECL for 100BASE‑FX fiber operation.
The device operates from a single 2.5 V power supply.
Typical power consumption is 250 mW per port.
Yes, the LXT9785E includes DTE detection to provide power over a CATS cable for IP‑telephony devices.