LimeSDR-Mini JTAG cable adapter

LimeSDR-Mini JTAG adapter

To directly program LimeSDR-Mini FPGA Intel MAX 10 (10M16SAU169C8G 169-UBGA), it is needed to connected JTAG adapter (Altera Blaster or equivalent). Standard FPGA JTAG connector has 10 pins in 2x5 configuration with 0.1" (2.54mm) pitch. Standard JTAG connector is too large for such a small PCB as LimeSDR-Mini. For this reason, LimeSSDR-Mini has 2 non-standard JTAG programming connectors:

• 7 pin (0.1") male header on the board edge (unpopulated)
• 10 pin (0.05") female header (unpopulated)

7 pin JTAG connector on the board edge

To use this JTAG connector with standard JTAG adapter you need to make simple JTAG adapter. Below are shown LimeSDR-Mini JTAG edge adapter schematic. LED is optional component and is required only for power indication.

Figure 1. LimeSDR-Mini JTAG adapter schematic

BOM:

1. Header connector (pitch 0.1" (2.54mm));

2. Pinheader (7 pin, pitch 0.1" (2.54mm) ;

3. Flat Ribbon Cable (pitch 0.5" (1,27mm);

4. LED (3mm green)

5. Resistor (1k)

Figure 2. Assembled LimeSDR-Mini JTAG adapter and board

Figure 3. LimeSDR-Mini JTAG adapter connected to the board

Figure 4. LimeSDR-Mini JTAG adapter connected to the board

10 pin JTAG connector

This connector has standard FPGA JTAG pinout pinout, but smaller pitch (0.05").

Figure 5. Assembled LimeSDR 0.1" to 0.05" JTAG adapter

BOM:

1. Header connector (pitch 0.100" (2.54mm));

2. Female Socket (0.05" (1.27mm));

3. Flat Ribbon Cable (pitch: 0.025" (0.64mm)).