Emerson RTM-ATCA-F140, Installation And Use Manual

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Functional Description
RTM-ATCA-F140 Installation and Use (6806800M97A)
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The Xilinx Spartan 3A FPGA does not include I/O pad protection diodes unless configured for
PCI operation and therefore there is no issue with the signals connected directly to the FPGA
either.
The 156.25MHz Synchronous Ethernet reference clock from the front blade to the RTM is AC-
coupled on the front blade using 10nF capacitors prior to being buffered to prevent DC current
flow.
4.11 Power Management
The front-blade provides two separate power supplies using the Zone 3 connectors:

+3.3 V management power — one pin

+12 V payload power — four pins
The maximum current draw, which is limited by the pin’s current handling capability, is 0.8A for
the management power and 3.2A for the payload power.
The management power is used to directly power the devices connected to the front blade I2C
bus, namely for serial EEPROM, temperature sensors and I/O extender device.
+12V payload power is the source for the onboard DC to DC converters needed for the RTM
payload.
4.11.1 Power Requirements
The table below summarizes the power requirements of the RTM-ATCA-F140.
Table 4-15 Power Requirements
Voltage
Maximum Current
+3.3V Management 0.2A
+12V Payload 2.1A
EA Version