SPI/I2C-USB-Interface
The USB SPI/I2C is a consolidated, 19” rack-mountable interface for establishing fast and reliable connections between a USB compatible host PC and any SPI or I2C bus system. It is equipped with a full-speed USB 2.0 port, providing a data rate of 12Mb/s.
The interface offers overvoltage protection of all inputs as well as short-circuit-proof outputs so that permanent availability can be guaranteed despite of faults and voltage variations. The voltage level for the SPI and I2C bus is adjustable to 3.3V, 5V and to an externally defined level.
All programmable components of the interface (ARM controller by NXP, CPLD by Xilinx) can be updated by reinstalling new firmware. For this purpose, a special programming adapter is available. In addition to that, evaluation software including drivers is available for different programming environments. The interface can be connected via C++, DLL or LabVIEW.
The SPI interface offers master/slave functionality. Four different SPI operating modes are available. SPI timing and SPI output level can be adjusted individually. The SPI interface can work at clock frequencies up to 4MHz. Its phase jitter is less than 8ns. The SPI output is equipped with ESD protection and includes an emergency shutdown for cases of permanent overload. SPI timing is carried out according to a 1μs pattern.
The I2C interface can be operated as master or slave providing a selectable clock frequency up to 100 kHz. The I2C output is equipped with ESD protection. The address range of the I2C bus is 7 bit.
A time stamp is generated based on a 32 bit counter being incremented every 100 µs.
The interface is a bus-powered device having a current consumption of 400mA. It has very small dimensions: 6.5“ x 4.13“ x 1.38“. The OEM version is built in Euro-card size: 6.3“ x 3.94“. The chassis is mechanically robust and does not weight more than 1.16 lbs. The OEM chassis only weighs about 0.18 lbs.
The interface offers overvoltage protection of all inputs as well as short-circuit-proof outputs so that permanent availability can be guaranteed despite of faults and voltage variations. The voltage level for the SPI and I2C bus is adjustable to 3.3V, 5V and to an externally defined level.
All programmable components of the interface (ARM controller by NXP, CPLD by Xilinx) can be updated by reinstalling new firmware. For this purpose, a special programming adapter is available. In addition to that, evaluation software including drivers is available for different programming environments. The interface can be connected via C++, DLL or LabVIEW.
The SPI interface offers master/slave functionality. Four different SPI operating modes are available. SPI timing and SPI output level can be adjusted individually. The SPI interface can work at clock frequencies up to 4MHz. Its phase jitter is less than 8ns. The SPI output is equipped with ESD protection and includes an emergency shutdown for cases of permanent overload. SPI timing is carried out according to a 1μs pattern.
The I2C interface can be operated as master or slave providing a selectable clock frequency up to 100 kHz. The I2C output is equipped with ESD protection. The address range of the I2C bus is 7 bit.
A time stamp is generated based on a 32 bit counter being incremented every 100 µs.
The interface is a bus-powered device having a current consumption of 400mA. It has very small dimensions: 6.5“ x 4.13“ x 1.38“. The OEM version is built in Euro-card size: 6.3“ x 3.94“. The chassis is mechanically robust and does not weight more than 1.16 lbs. The OEM chassis only weighs about 0.18 lbs.
Advantages
- Bus powered device
- full-speed (12Mb/s) USB port
- 400kHz I2C master/slave clock rate, adjustable
- 1 MHz SPI master/slave clock rate, adjustable
- surge protection and short-circuit-proof outputs
- SPI/I2C level adjustable (3,3V, 5V, extern)
- 7 bit I2C addressing
- 4 SPI modes
- 32 Bit Counter for timestamp, all 100 μs increment
- 19” rack mountable
Conclusion
The USB SPI/I2C is a compact, fast and reliable interface for connecting a host PC to an SPI or I2C bus system via USB. Because of its integrated over load and short circuit protection the interfaces provides better security and reliability for the overall system.