LimeSDR-USB hardware description

LimeSDR-USB Board Key Features

The LimeSDR-USB development board provides a hardware platform for developing and prototyping high-performance and logic-intensive digital and RF designs using Altera’s Cyclone IV FPGA and Lime Microsystems transceiver.

The LimeSDR-USB has two different USB connector versions. LimeSDR-USB 1v4 is micro USB type B connector (socket) based, as shown in Figure 1. LimeSDR-USB 1v4s is a USB type A connector (plug) based, as shown in Figure 2.

Figure 1. LimeSDR-USB 1v4 – micro USB type B connector board

Figure 2. LimeSDR-USB 1v4s – USB type A connector board

LimeSDR-USB board features:

• USB Interface
  • Cypress FX3 Super Speed USB 3rd generation controller

• FPGA Features
  • Cyclone IV EP4CE40F23C8N device in 484-pin FPGA
  • 39’600 logic elements
  • 1134 Kbits embedded memory
  • 116 embedded 18x18 multipliers
  • 4 PLLs

• FPGA Configuration
  • JTAG mode configuration
  • Active serial mode configuration
  • Possibility to update FPGA gateware by using FX3 (USB)

• Memory Devices
  • 2x 1Gbit (64M x 16) DDR2 SDRAM
  • 4Mbit flash for FX3 firmware
  • 16Mbit flash for FPGA gateware
  • 2 x 128K (16K x 8) EEPROMs for LMS MCU firmware, LMS MCU data
  • 1 x 64K (8K x 8) EEPROM for FX3 data

• Connections
  • microUSB3.0 (type B) connector or USB3.0 (type A) plug
  • Coaxial RF (U.FL) connectors
  • FPGA GPIO headers (0.05” pitch)
  • FPGA and FX3 JTAG connectors (0.05” pitch)
  • 6..12V DC power jack and pinheader
  • Fan connector (3.3V)

• Clock System
  • 30.72MHz VCTCXO (precision: ±1 ppm initial, ±4 ppm stable).
  • Possibility to lock VCTCXO to external clock or tune VCTCXO by onboard DAC
  • Programmable clock generator for the FPGA reference clock input or LMS PLLs

• Board Size 60mm x 100mm (2.36” x 3.94”)

LimeSDR-USB board overview

LimeSDR-USB board version 1.4 picture with highlighted major connections presented in Figure 3. There are three connector types – data and debugging (USB3.0, FPGA GPIO and JTAG), power (DC jack and external supply pinheader) and high frequency (RF and reference clock).

Figure 3. LimeSDR-USB 1v4 Development Board Connectors

Board components description listed in the Table 1 and Table 2.

Table 1. Board components

Board reference	Type	Description
IC1	FPRF	Field programmable RF transceiver, LMS7002M
IC8	FPGA	Altera Cyclone IV, EP4CE40F23C8N 484-BGA
IC13	USB 3.0 microcontroller	Cypress FX3 Super Speed USB 3rd generation controller, CYUSB3014