|Title||PMOD CAN CONTROLLER MCP25625|
|Datasheet||Download 410-353 datasheet
|Others parts numbering|
|MCP25625-E/SS: IC TXRX CAN CTLR EXT TEMP 28SSOP|
|MCP25625-E/ML: IC TXRX CAN CTLR EXT TEMP 28QFN|
The Digilent Pmod interface is used to connect low frequency, low I/O pin count peripheral modules to host controller boards. There are six-pin and twelve-pin versions of the interface defined, encompassing SPI, I²C, UART, I2S, H-bridge and GPIO protocols. The six-pin version provides four digital I/O signal pins, one power pin and one ground pin. The twelve-pin version provides eight I/O signal pins, two power pins and two ground pins. The signals of the twelve-pin version are arranged so that it provides two of the six-pin interfaces stacked. In general, Pmod modules can plug directly into connectors on the host controller board, called host ports, or be connected to the controller board via six-pin or twelve-pin cables. Two six-pin peripheral modules can be connected to a single twelve-pin host port via a twelve-pin to dual six-pin splitter cable. Similarly, a single twelvepin peripheral module can be connected to two six-pin host ports via the same twelve-pin to dual six-pin splitter cable. Pmod modules are powered by the host via the interface's power and ground pins. The Pmod interface is not intended for high frequency operation, however, using RJ45 connectors and twisted pair Ethernet cable, signals have been sent reliably at 24 MHz and distances to 4 meters. Theoretically, signal speeds greater than 100 MHz should be achievable using high-speed ports with direct connection of Pmod modules (without the use of cables).
The digital signal characteristics are not specified. However, the general expectation is that 3.3 V logic power supply will be used and the signals will conform to LVCMOS V or LVTTL 3.3 V logic conventions. The driver current source/sink capability isn't specified and depends on the capabilities of the specific system board or module. The I/O pins on the system board are generally directly driven by the FPGA or microcontroller. The drive strength for FPGA pins is generally in the range to +/-24 mA. The drive capability of microcontrollers is generally less and some of them are not symmetrical. The drive strength for microcontroller pins is generally in the range to +/-10 mA. The I/O pins on standard system board Pmod ports generally have ESD protection diodes and 200-ohm series resistors. The resistors are to limit short circuit currents if pins are inadvertently shorted, or to protect against driver conflicts if outputs are inadvertently connected together. High-speed Pmod ports are present on some Digilent system boards and do not have ESD protection diodes or series resistors.
Digilent PmodTM Interface Specification 1.1.0 Peripheral modules may be connected to the host via cables 18" in length. The drivers on the host or peripheral module should have sufficient drive strength to drive this length of cable at whatever the operating speed of the interface on the Pmod is expected to be. In general, this means that the driver should be able to source or sink at least mA of current. With the exception of I2C connected modules, peripheral modules may not assume that pull-up or pull-down resistors are present on the host and must provide for proper termination of inputs, if necessary, and may not use open drain or open collector outputs, unless the pull-up is provided on the peripheral module itself. For all I2C connected modules, the digital signal characteristics conform to the I 2C specification. Either 3.3 V levels can be used on most modules, but Digilent system boards operate 3.3 V, and the modules are primarily intended for operation 3.3 V. Prior to the Digilent Pmod Interface Specification 1.1.0, I2C modules were not required to have onboard pull-ups. Therefore, it is suggested to include jumpered pull-ups on system boards to be backward compatible with old I2C Pmods. However, all Pmods designed to conform to specification version 1.1.0 and higher will include onboard pull-ups that can be jumpered in and out.
The power pins of the interface provide power from the host to the peripheral. The complete interface requires that the host provide the ability to switch the voltage on the power pins between 5.0 V and V. A reduced functionality subset of the specification allows the host to provide only V at the power supply pins, with no ability to switch. On the twelve-pin version of the interface, both power supply pins switch together and always supply the same voltage. These pins may be shorted together at either the host end or the peripheral end. On I2C connected modules, the power pin of the interface provides power from the system board to the peripheral module. The supplied voltage will generally 3.3 V, but operation V is supported by some modules. Daisy chaining six-pin I2C connected modules is possible via the female connector on the board edge opposite the male connector. The amount of power a peripheral module is allowed to draw from the host is not specified, but should not be assumed to be more than approximately 100 mA.
Pmod connections are made using standard 100 mil spaced, 25 mil square, pin-header style connectors. The peripheral module board will have a male connector. This will typically be a right-angle connector, at the board edge, for direct connection to a host board. Some older I²C modules have a straight male connector inboard from the board edge as only cable connections were intended to be used. Beginning with Pmod Specification 1.1.0, all connectors intended for primary connection to a host board should be right angle male connectors. Six-pin I²C modules will have a six-pin female connector, centered on the board edge opposite the male connector. This will typically be a right-angle connector at the board edge and is intended to be used in daisy chaining. The host board will typically have a 12-pin right angle female connector at the board edge for direct connection of peripheral module boards, however a straight female connector inboard from the board edge is also allowed.
Digilent PmodTM Interface Specification 1.1.0 When multiple Pmod host ports are placed side-by-side along a host board edge, they are spaced 0.9" center-tocenter. This allows for 0.8" wide modules to be plugged side-by-side into a host without mechanical interference. Peripheral modules with multiple male connectors must also have them spaced on 0.9" centers for direct connection to a host. Peripheral modules with a single connector that are intended for direct connection to a host, or that are intended to fit into the Pmod mounting clip, should be 0.8" wide. There should be >25 mil of clearance from the board edge to any components to allow clearance for the Pmod clip to latch the board edge. The connector should be centered along the 0.8" side of the module. Peripheral modules that are more than 0.8" wide can be directly connected to a host in most cases but may interfere with adjacent host ports. The following diagrams show physical connector placement and pin numbering conventions for the host (system board) and peripheral module sides of the connection. Note that the pin numbering conventions for the 2x6 connectors are non-standard and are mirrored between the host connector and the peripheral board connector.Figure 1. Standard 6-pin male connector placement on Pmod boards.
|Some Part number from the same manufacture DIGILENT|