| 1 | [[TracNav(HardwareUsersGuides/CM-PLL/TOC)]] |
| 2 | |
| 3 | = CM-PLL Clock Module: Connectors = |
| 4 | |
| 5 | The CM-PLL board has 3 connectors for external cable connections: |
| 6 | * MMCX jack |
| 7 | * Board-to-board Header In |
| 8 | * Board-to-board Header Out |
| 9 | |
| 10 | [[Image(wiki:HardwareUsersGuides/CM-PLL/files:connectors.png, nolink)]] |
| 11 | |
| 12 | || [[Image(wiki:HardwareUsersGuides/WARPv3/files:important.png,nolink,valign=middle)]] || The WARP v3 board should be powered off before any cables are connected or disconnected from the CM-PLL connectors. The equipment driving the cables should also be powered off when making connections. || |
| 13 | |
| 14 | == MMCX Jack == |
| 15 | |
| 16 | The MMAC jack is used to feed a reference clock signal from external equipment, such as test equipment with a 10MHz reference output. This connector is a standard-polarity, standard-gender 50-ohm MMCX jack, also known as a MMCX female connector. The mating cable should have a 50 ohm MMCX plug (male connector). |
| 17 | |
| 18 | The MMCX jack feeds a simple circuit which converts the single-ended input signal into a differential signal, which then drives one of the inputs of the reference clock mux. The MMCX reference input can be selected with the appropriate [wiki:../Configuration#ReferenceClockSource DIP switch setting]. |
| 19 | |
| 20 | The MMCX reference input presents a 50-ohm load and requires a clock signal amplitude at least 800mVp-p. |
| 21 | |
| 22 | The reference designs which use the CM-PLL and [wiki:cores/w3_clock_controller w3_clock_controller core] assume a 10MHz reference frequency. However the AD9511 PLL can be configured for a wide range of reference frequencies. Refer to the AD9511 datasheet for details on appropriate divider settings for alternate reference frequencies. Custom divider settings can be implemented using the [wiki:cores/w3_clock_controller#CustomConfigurations w3_clock_controller custom config] feature. |
| 23 | |
| 24 | == Board-to-Board Headers == |
| 25 | |
| 26 | The board-to-board headers are designed to support daisy chaining multiple WARP v3 kits equipped with CM-PLL modules. The "In" header dedicates one pin to a reference clock input, selected by the appropriate [wiki:../Configuration#ReferenceClockSource DIP switch setting]. The "Out" header dedicates one pin to a copy of the reference clock signal. This output can be enabled or disabled via [wiki:../Configuration#ReferenceClockOutput via the DIP switch]. |
| 27 | |
| 28 | Each header also has 4 pins tied to dedicated FPGA I/O. These FPGA pins are bidirectional. User designs can assign the pins whatever function the application requires. The [wiki:WARPLab WARPLab reference design], for example, uses the 4 I/O on the "In" header as trigger inputs, and 4 I/O on the "Out" header as trigger outputs. |
| 29 | |
| 30 | The 8 FPGA I/O pins routed to the board-to-board headers use 2.5v levels. These pins are '''not''' 3.3v tolerant. |
| 31 | |
| 32 | The board-to-board headers are 5x2-pin [http://www.samtec.com/technical-specifications/Default.aspx?seriesMaster=tfm Samtec TFM series connectors], part number 105-02-S-D-WT. |
| 33 | |
| 34 | === Pinout === |
| 35 | The pinout of the two headers is specified below. The figure is oriented the same as the photo above. |
| 36 | |
| 37 | [[Image(wiki:HardwareUsersGuides/CM-PLL/files:brd_to_brd_conns, nolink)]] |
| 38 | |
| 39 | ||||= '''In''' Header =|| |
| 40 | || Pin || Function || Specs || |
| 41 | || 1 || Reference Clock Input || Single-ended clock signal, 3.3v max || |
| 42 | || 3 || HDR_IN<0> || FPGA Pin V28 || |
| 43 | || 5 || HDR_IN<1> || FPGA Pin V27 || |
| 44 | || 7 || HDR_IN<2> || FPGA Pin V33 || |
| 45 | || 9 || HDR_IN<3> || FPGA Pin V34 || |
| 46 | || (2,4,6,8,10] || Ground |||| |
| 47 | |
| 48 | |
| 49 | |
| 50 | === Cables === |
| 51 | There are multiple cable options: |