Spesifikasi
RTL8365MB‑CG is a Layer 2 managed 4+1 port Gigabit Ethernet switch controller developed by Realtek Semiconductor, integrating 4 channels of built-in 10/100/1000M PHY transceivers, non-blocking switching core and on-chip packet buffer SRAM inside a single chip, which is a compact cost-effective switching solution for small network devices.
Part Number Definition
RTL8365MB refers to the core model with 4 integrated copper PHY ports plus one configurable uplink GMAC interface. CG stands for LQFP-128 surface mount package with exposed thermal pad. The factory adopts tape-and-reel packaging by default to match automatic SMT patch assembly.
Core Port and Protocol Specifications
The chip is equipped with 4 independent RJ45 ports embedded with Gigabit PHY circuits, fully compliant with IEEE 802.3 10BASE-T, IEEE 802.3u 100BASE-TX, IEEE 802.3ab 1000BASE-T and IEEE 802.3az Energy Efficient Ethernet protocols. All ports support automatic negotiation of transmission rate and duplex mode. Full duplex mode is available under 10M, 100M and 1000M working conditions, while half duplex only supports 10M and 100M rates. Every port integrates Auto-MDI/MDIX automatic cable pin sequence correction function, so users do not need to distinguish straight-through or crossover network cables. One reserved extended GMAC port can be flexibly switched between RGMII and MII modes to connect main control processors, wireless router SoC or external fiber optical modules to realize fiber network uplink expansion. It adopts wire-speed non-blocking store-and-forward forwarding architecture, supports jumbo frame transmission up to 9216 bytes. The on-chip MAC address table can store up to 8K address entries, supporting automatic address learning, aging and static binding functions, with 128KB built-in packet buffer memory to ensure stable data forwarding under burst traffic.
Management and QoS Functional Features
It supports port-based VLAN, 802.1Q tagged VLAN, port isolation and broadcast & multicast storm suppression. The built-in 8-level QoS priority queue mechanism can classify data transmission priority according to port number, 802.1p VLAN tag and DSCP field, ensuring low-latency priority forwarding for voice, video and key business data. Other practical functions include port mirroring, ingress and egress bidirectional bandwidth rate limiting, spanning tree protocol to prevent Layer 2 network loops, and cable diagnosis function to detect cable open circuit, short circuit and cable length faults. System configuration parameters can be automatically loaded from external EEPROM after power-on startup. Upper-level MCU can complete register reading, writing and function configuration through SMI serial management bus.
Power Supply and Clock Design
The chip adopts dual power supply architecture. The I/O peripheral circuit uses 3.3V power input, and the internal integrated LDO linear regulator generates 1.0V core operating voltage to simplify the design of peripheral power supply circuits. Only one external 25MHz passive crystal oscillator is required to provide the system reference clock source. Multiple low-power dormant modes and link idle power saving mechanisms are embedded to reduce overall power consumption when ports are disconnected or in idle state. Each network port corresponds to independent LED indicator pins to display link connection status, transmission rate and data activity.
Package and Mechanical Information
The packaging type is 128-pin LQFP quad flat leaded package with exposed thermal pad. The moisture sensitivity level is MSL 3, and reflow soldering must be finished within 168 hours after opening the vacuum moisture-proof packaging bag. The exposed thermal pad at the bottom effectively reduces thermal resistance and improves heat dissipation efficiency during long-term high-load continuous data forwarding, enhancing the long-term operation stability of the chip.
Environmental and Compliance Standards
The operating ambient temperature range is 0 ℃ to +70 ℃. The product is fully lead-free, and meets RoHS and REACH environmental protection standards without containing restricted hazardous substances. Optimized EMC electromagnetic interference suppression design strengthens anti-interference ability, adapting to consumer network terminals and light industrial control network working environments.
Skenario Aplikasi Umum
5-port desktop managed and unmanaged Gigabit switches and small industrial Ethernet switches Home broadband wireless routers, gateway equipment and IPTV set-top box internal switching core NVR video recording hosts and multi-channel IP camera monitoring system wired network processing unit Intelligent building wiring equipment, protocol conversion gateways and embedded multi-port network expansion boards Small office network distribution terminals, PoE switch main control switching chips and low-cost wired access modules
LXB Semicon supplies original Realtek RTL8365MB‑CG 4+1 port Layer 2 managed Gigabit Ethernet switch IC
