BCM5461SA3KFBG

BCM5461SA3KFBG is Broadcom’s single-port Gigabit Ethernet PHY in a Fine-Pitch FBGA package. It provides the physical layer for 10/100/1000BASE-T networks and connects to a MAC via MII or RMII.
Key points:
- 10/100/1000BASE-T PHY with auto-negotiation and full/half-duplex operation.
- Interfaces to a MAC via MII/RMII; requires external Ethernet magnetics and standard PHY LED pins.
- Packaged in a high-density FBGA (A3K variant) suitable for embedded NICs, motherboards, and network adapters.
- Includes analog front-end/line drivers and typical PHY utilities; designed for Broadcom’s PHY ecosystem.
Usage note:
- For exact electrical specs, pinout, timing, and package dimensions, refer to the BCM5461SA3KFBG datasheet and packaging drawings from Broadcom.
If you need a quick spec snippet or package drawing, I can summarize the official datasheet sections you’re after.

BCM5461SA3KFBG is Broadcom’s 1-port 10/100/1000BASE‑T Ethernet PHY. Direct equivalents in the Broadcom BCM5461 family include BCM5461S and BCM5461 (alternate packages/RoHS options). Cross‑vendor equivalents (not pin‑compatible) commonly used: Realtek RTL8211/RTL8211F, Microchip KSZ9021, and Marvell 88E1111. For an exact cross-reference by package/revision, consult Broadcom’s cross-reference database or a distributor’s cross-reference tool.

Here are the typical features of Broadcom BCM5461SA3KFBG:
- 1-port 10/100/1000BASE-T copper Ethernet PHY
- RJ-45 interface (external magnetics typically required)
- Auto-Negotiation and Auto-MDIX
- Full-/half-duplex support
- IEEE 802.3az Energy Efficient Ethernet (EEE)
- Flow control via Pause frames
- Cable Diagnostics and link status indicators
- MAC interface options to host (GMII/MII for gigabit, other modes per design)
- RoHS-compliant Pb-free packaging (SMD)
- Commonly provided in a 48-pin QFN/related package (suffix reflects packaging)
Note: exact packaging and interface options may vary by variant; refer to the datasheet for precise pinout and supply requirements.

- Pin count: 28 pins
- Function: Single-port 10/100/1000BASE-T Ethernet PHY (Ethernet physical-layer transceiver) interfacing to the MAC via MII/RMII/RGMII.

Manufacturer: Broadcom Inc.
Broadcom Inc. is a multinational technology company that designs, develops, and sells semiconductors and infrastructure software for networking, data center, wireless, storage, and broadband applications.

BCM5461SA3KFBG is a 10/100/1000BASE-T Ethernet PHY. Typical applications:
- PCI/PCIe NICs and other host Ethernet interfaces (desktop, server, embedded)
- Embedded LAN in consumer electronics (set-top boxes, NAS, printers, smart TVs, IP cameras)
- Ethernet switches, routers, gateways, and other network appliances
- Industrial Ethernet and control systems needing a robust single-port PHY
In short: any design requiring a single 10/100/1000BASE-T PHY interfaced to a MAC.

FBGA (Fine-pitch Ball Grid Array) package, RoHS-compliant.