FPC401 Quad Port Controller
1 Features
- Supports Control Signal Management and I2C Aggregation Across Four Ports
- Combine Multiple FPC401s to Control 56 Total Ports Through a Single Host Interface
- Eliminates Need for Discrete I2C Muxes, LED Drivers, and High-Pin-Count FPGA/CPLD Control Devices
- Reduces PCB Routing Complexity by Handling All Low-Speed Control Signals Close to the Port
- Selectable I2C (Up to 1 MHz) or SPI (Up to 10 MHz) Host Control Interface
- Automatic Pre-Fetching of Critical, User-Specified Data From the Modules
- Low Single-Port and Multi-Port Read/Write Latency: <50 µs for SPI Mode, <400 µs for I2C Mode
- Broadcast Mode Allows Writes to All Ports Simultaneously Across All FPC401 Controllers
- Advanced LED Features for Port Status Indication, Including Programmable Blinking and Dimming
- Customizable Interrupt Events
- Separate Host-Side I/O Voltage: 1.8-V to 3.3-V
- Small QFN Package Enabling Placement on Bottom Side of PCB Underneath Ports
2 Applications
- ToR/Aggregation/Core Switch and Router SFP+/QSFP+ Port Control
- SAS External Cable Management Interface Control
- Video Switch & Router SFP+/QSFP+ Port Control
3 Description
The FPC401 quad port controller serves as a low-speed signal aggregator for common port types such as SFP+, QSFP+, and SAS. The FPC401 aggregates all low-speed control and I2C signals across four ports and presents a single easy-to-use management interface to the host (I2C or SPI). Multiple FPC401s can be used in high-port-count applications with one common control interface to the host. The FPC401 is designed to allow placement on the bottom side of the PCB, underneath the press fit connector, to simplify routing. This localized control of the ports’ low-speed signals cuts system BOM cost by enabling the use of smaller IO count control devices (FPGAs, CPLDs, MCUs) and by reducing routing layer congestion.
Device Information(1)
| PART NUMBER | PACKAGE | BODY SIZE (NOM) |
|---|---|---|
| FPC401 | QFN (56) | 5.00 mm × 11.00 mm |
- For all available packages, see the orderable addendum at the end of the data sheet.
Simplified Block Diagram
4 Revision History
| DATE | REVISION | NOTES |
|---|---|---|
| December 2016 | * | Initial release. |
5 Description (continued)
The FPC401 is compatible with standard SFF-8431, SFF-8436, and SFF-8449 low-speed management interfaces, including a dedicated 100-kHz and 400-kHz I2C interface to each port. Additional general-purpose pins are available to perform functions such as driving port status LEDs or controlling power switches. The LED drivers have convenience features such as programmable blinking and dimming. The interface to the host controller can operate on a separate supply voltage between 1.8-V and 3.3-V to support low-voltage I/Os.
The FPC401 can prefetch data from user-specified registers in each module, making the data readily accessible to the host through a fast I2C (up to 1 MHz) or SPI (up to 10 MHz) interface. In addition, the FPC401 can trigger an interrupt to the host whenever critical, user-configurable events occur associated with any of the ports under its control. This eliminates the need to continuously poll the modules.
