CoolRunner-II CPLD breakout board
|Name:||CoolRunner-II CPLD breakout board|
|Buy it:||Get one for $15 at Seeed Studio|
|Forum:||CoolRunner-II CPLD breakout board Forum|
Ever get stuck choosing the right logic chip combination or voltage level translator? Give up the hunt and create your own custom logic chip. CPLDs can give you the logic you need, with the pinout you want, while saving board space and board revisions.
The CoolRunner-II XC2C CPLD has two separate banks of pins that can operate at different voltages, internal pull-up resistors, and pin keepers. This development board from Dangerous Prototypes will help you build your first custom logic chip using simple schematic entry, Verilog, or VHDL.
- XC2C64A CPLD with 64 macrocells
- On-board 1.8volt supply for the core
- On-board 3.3volt supply for pins
- Separate pin banks can be operated at different voltages (1.2volt to 3.3volt)
- Selectable 1.8volt, 3.3volt, and external supply for each pin bank
- LEDs for output
- Push button for input
- Populated JTAG header
- Unpopulated oscillator footprint on bottom
- Easy to program with the Bus Pirate and Bus Blaster
- Pre-programmed with LED inverse toggle demo
- Open source (CC-BY-SA)
The XC2C64A (U1) is a 64 macrocell CPLD with two separate IO banks for voltage translation. It is one of the smallest CPLDs made by Xilinx, and is readily available from Digikey for around $2.65.
The CPLD core requires a 1.8volt supply to each VINT pin. This supply is provided by an on-board 1.8volt regulator.
The IO pins are divided into two banks that each operate from a separate supply of 1.2volts to 3.3volts. An external supply can be connected to either IO pin, or place a jumper on the V1 and V2 pins to select the on-board 1.8volt or 3.3volt power supply.
Each supply pin has a 0.1uF capacitor (C1,C2,C3,C4).
The JTAG programming pins are brought to header JT. The JTAG interface is powered by the 3.3volt core supply.
- For more see the Xilinx CoolRunner-II CPLD quick start
A 1.8volt regulator (U2) powers the CPLD core and (optionally) the IO pins, which a second 3.3volt regulator (U3) is available to power the IO pin. C5, C6, C7, and C9 are 3.3uF capacitors on the regulator supply and output.
Both regulators are supplied through pin V+. The supply can be up to 5volts. Up to 100mA is available from the 3v3 pin.
LED PWR lights if the power supply is active.
Buttons and LEDs
Two LEDs (D1, D2) and a push button (PB) are included for a little user IO.
LED D1 and D2 source current from the CPLD. Generally, designers sink current from CPLDs and FPGAs - the chip connects the LED to ground instead of power - because many parts can sink 20mA but only source a few. On this chip, however, the maximum current is a paltry 4mA for both source and sink. The LEDs have 2K resistors (R2,R3) that keep the current at an acceptable 2mA.
A push button (PB) provides a way for user input. Resistor R1 is a pullup for the button, it is not populated because the CoolRunner-II chips have internal pull-ups on each pin.
|GND||Ground connection||Ground connection||GND|
|V+||Supply voltage (max 5volts)||3.3volt output (max 100mA)||3V3|
|V2||Bank 2 IO external supply (1.2-3.3volts)||1.8volt output (max 50mA)||1V8|
|18||Push button||Bank 1 IO external supply||V1|
|38||LED D2||LED D1||39|
|D1, D2, PWR||3||LED||LED-805|
|JTAG||1||0.1” Pin header||1X06|
|PB||1||SMD button, small||TACT_SWITCH_SMALL|
|U2||1||1.8volt LDO voltage regulator 100mA||SOT-23-5|
|U3||1||3.3volt LDO voltage regulator 150mA||SOT-23-5|
|V1,V2||2||0.1” Pin header||1X03|
Q1 on the bottom of the PCB is for an optional 3.3volt oscillator. It feeds into a global clock pin. Some suitable values are:
Development and programming tutorials are on the main CPLD page.
You can get one for $15, including worldwide shipping.
Your purchases at Seeed Studio keep the open source project coming, we sincerely appreciate your support!
- CPLD breakout homepage Programming, tutorials, devices, and more
- CoolRunner-II CPLD quick start
- CoolRunner-II family manual
- XC2C64A device datasheet
- XC2C32A device datasheet (smaller version of XC2C64A used on Bus Blaster v2)