FPGA可编程逻辑器件芯片XC95216-15PQG160I中文规格书
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Spartan-3 FPGA Family: DC and Switching CharacteristicsThe capacitive load (C L ) is connected between the output and GND. The Output timing for all standards, as published in the speed files and the data sheet, is always based on a C L value of zero . High-impedance probes (less than 1 pF) are used for all measurements. Any delay that the test fixture might contribute to test measurements is subtracted from those measurements to produce the final timing numbers as published in the speed files and data sheet.Using IBIS Models to Simulate Load Conditions in ApplicationIBIS Models permit the most accurate prediction of timing delays for a given application. The parameters found in the IBIS model (V REF , R REF , and V MEAS ) correspond directly with the parameters used in T able 48, V T , R T , and V M . Do not confuse V REF (the termination voltage) from the IBIS model with V REF (the input-switching threshold) from the table. A fourthparameter, C REF , is always zero. The four parameters describe all relevant output test conditions. IBIS models are found in the Xilinx development software as well as at the following link.Simulate delays for a given application according to its specific load conditions as follows:1.Simulate the desired signal standard with the output driver connected to the test setup shown in Figure 35. Useparameter values V T , R T , and V M from Table 48. C REF is zero.2.Record the time to V M .3.Simulate the same signal standard with the output driver connected to the PCB trace with load. Use the appropriate IBISmodel (including V REF , R REF , C REF , and V MEAS values) or capacitive value to represent the load.4.Record the time to V MEAS .pare the results of steps 2 and 4. The increase (or decrease) in delay should be added to (or subtracted from) theappropriate Output standard adjustment (T able 47) to yield the worst-case delay of the PCB trace.DIFF_SSTL2_II -V ICM – 0.75V ICM + 0.75501.25V ICMDIFF_SSTL2_II_DCI Notes:1.Descriptions of the relevant symbols are as follows:VREF – The reference voltage for setting the input switching threshold VICM – The common mode input voltageVM – Voltage of measurement point on signal transition VL – Low-level test voltage at Input pin VH – High-level test voltage at Input pinRT – Effective termination resistance, which takes on a value of 1MW when no parallel termination is required VT – Termination voltage2.The load capacitance (CL) at the Output pin is 0 pF for all signal standards.3.According to the PCI specification.Table 48:Test Methods for Timing Measurement at I/Os (Cont’d)Signal Standard (IOSTANDARD)InputsOutputsInputs and OutputsV REF (V)V L (V)V H (V)R T (Ω)V T (V)V M (V)Table 70:Spartan-3 FPGA Pin DefinitionsPin Name Direction Description I/O: General-purpose I/O pinsI/O User-defined as input, output,bidirectional, three-state output,open-drain output, open-sourceoutput User I/O:Unrestricted single-ended user-I/O pin. Supports all I/O standards except the differential standards.I/O_Lxxy_#User-defined as input, output,bidirectional, three-state output,open-drain output, open-sourceoutput User I/O, Half of Differential Pair:Unrestricted single-ended user-I/O pin or half of a differential pair. Supports all I/O standards including the differential standards.DUAL: Dual-purpose configuration pinsIO_Lxxy_#/DIN/D0, IO_Lxxy_#/D1,IO_Lxxy_#/D2,IO_Lxxy_#/D3,IO_Lxxy_#/D4,IO_Lxxy_#/D5,IO_Lxxy_#/D6,IO_Lxxy_#/D7Input during configurationPossible bidirectional I/O afterconfiguration if SelectMap port isretainedOtherwise, user I/O afterconfigurationConfiguration Data Port:In Parallel (SelectMAP) modes, D0-D7 are byte-wide configuration datapins. These pins become user I/Os after configuration unless theSelectMAP port is retained via the Persist bitstream option.In Serial modes, DIN (D0) serves as the single configuration data input.This pin becomes a user I/O after configuration unless retained by thePersist bitstream option.IO_Lxxy_#/CS_B Input during Parallel modeconfigurationPossible input after configuration if SelectMap port is retained Otherwise, user I/O after configuration Chip Select for Parallel Mode Configuration:In Parallel (SelectMAP) modes, this is the active-Low Chip Select signal. This pin becomes a user I/O after configuration unless the SelectMAP port is retained via the Persist bitstream option.IO_Lxxy_#/RDWR_B Input during Parallel modeconfigurationPossible input after configurationif SelectMap port is retainedOtherwise, user I/O afterconfiguration Read/Write Control for Parallel Mode Configuration:In Parallel (SelectMAP) modes, this is the active-Low Write Enable, active-High Read Enable signal. This pin becomes a user I/O after configuration unless the SelectMAP port is retained via the Persist bitstream option.IO_Lxxy_#/ BUSY/DOUT Output during configurationPossible output afterconfiguration if SelectMap port isretainedOtherwise, user I/O afterconfigurationConfiguration Data Rate Control for Parallel Mode, Serial DataOutput for Serial Mode:In Parallel (SelectMAP) modes, BUSY throttles the rate at whichconfiguration data is loaded. This pin becomes a user I/O afterconfiguration unless the SelectMAP port is retained via the Persistbitstream option.In Serial modes, DOUT provides preamble and configuration data todownstream devices in a multi-FPGA daisy-chain. This pin becomes auser I/O after configuration.IO_Lxxy_#/INIT_B Bidirectional (open-drain) duringconfigurationUser I/O after configuration Initializing Configuration Memory/Detected Configuration Error: When Low, this pin indicates that configuration memory is being cleared. When held Low, this pin delays the start of configuration. After this pin is released or configuration memory is cleared, the pin goes High. During configuration, a Low on this output indicates that a configuration data error occurred. This pin always has an internal pull-up resistor to VCCO_4 or VCCO_BOTTOM during configuration, regardless of the HSWAP_EN pin. This pin becomes a user I/O after configuration.DCI: Digitally Controlled Impedance reference resistor input pinsIO_Lxxy_#/VRN_# or IO/VRN_#Input when using DCIOtherwise, same as I/ODCI Reference Resistor for NMOS I/O Transistor (per bank):If using DCI, a 1% precision impedance-matching resistor is connectedbetween this pin and the VCCO supply for this bank. Otherwise, this pin isa user I/O.IO_Lxxy_#/VRP_# or IO/VRP_#Input when using DCIOtherwise, same as I/ODCI Reference Resistor for PMOS I/O Transistor (per bank):If using DCI, a 1% precision impedance-matching resistor is connectedbetween this pin and the ground supply. Otherwise, this pin is a user I/O.All VCCAUX inputs must be connected together and to the +2.5V voltage supply. Furthermore, there must be sufficient supply decoupling to guarantee problem-free operation, as described in XAPP623.Because VCCAUX connects to the DCMs and the DCMs are sensitive to voltage changes, be sure that the VCCAUX supply and the ground return paths are designed for low noise and low voltage drop, especially that caused by a large number of simultaneous switching I/Os.GND Type: GroundAll GND pins must be connected and have a low resistance path back to the various VCCO, VCCINT, and VCCAUX supplies.Pin Behavior During ConfigurationTable79 shows how various pins behave during the FPGA configuration process. The actual behavior depends on the values applied to the M2, M1, and M0 mode select pins and the HSWAP_EN pin. The mode select pins determine which of the DUAL type pins are active during configuration. In JT AG configuration mode, none of the DUAL-type pins are used for configuration and all behave as user-I/O pins.All DUAL-type pins not actively used during configuration and all I/O-type, DCI-type, VREF-type, GCLK-type pins are high impedance (floating, three-stated, Hi-Z) during the configuration process. These pins are indicated in Table79 as shaded table entries or cells. These pins have a pull-up resistor to their associated VCCO if the HSWAP_EN pin is Low. When HSWAP_EN is High, these pull-up resistors are disabled during configuration.Some pins always have an active pull-up resistor during configuration, regardless of the value applied to the HSWAP_EN pin. After configuration, these pull-up resistors are controlled by Bitstream Options.•All the dedicated CONFIG-type configuration pins (CCLK, PROG_B, DONE, M2, M1, M0, and HSWAP_EN) have a pull-up resistor to VCCAUX.•All JTAG-type pins (TCK, TDI, TMS, TDO) have a pull-up resistor to VCCAUX.•The INIT_B DUAL-purpose pin has a pull-up resistor to VCCO_4 or VCCO_BOTTOM, depending on package style. After configuration completes, some pins have optional behavior controlled by the configuration bitstream loaded into the part. For example, via the bitstream, all unused I/O pins can be collectively configured as input pins with either a pull-up resistor, a pull-down resistor, or be left in a high-impedance state.Table 79:Pin Behavior After Power-Up, During ConfigurationPin NameConfiguration Mode Settings <M2:M1:M0>BitstreamConfigurationOption Serial Modes SelectMap Parallel Modes JTAG Mode<1:0:1>Master <0:0:0>Slave <1:1:1>Master <0:1:1>Slave <1:1:0>I/O: General-purpose I/O pinsIO UnusedPinIO_Lxxy_#UnusedPin DUAL: Dual-purpose configuration pinsIO_Lxxy_#/DIN/D0DIN (I)DIN (I)D0 (I/O)D0 (I/O)Persist UnusedPinIO_Lxxy_#/D1D1 (I/O)D1 (I/O)Persist UnusedPinIO_Lxxy_#/D2D2 (I/O)D2 (I/O)Persist UnusedPinIO_Lxxy_#/D3D3 (I/O)D3 (I/O)Persist UnusedPinIO_Lxxy_#/D4D4 (I/O)D4 (I/O)Persist UnusedPin。