IBUFE3 - 2021.1 English

Primitive: Input Buffer with Offset Calibration and VREF Tuning

PRIMITIVE_GROUP: I/O
PRIMITIVE_SUBGROUP: INPUT_BUFFER

Introduction

The input buffer (IBUFE3) primitive is only supported in XP I/O banks. This primitive has functions similar to the IBUF_IBUFDISABLE with added controls for offset calibration and V_REF tuning, along with input buffer disable (IBUFDISABLE). The offset calibration feature is accessed using the OSC_EN and OSC[3:0] ports. The V_REF scan feature is accessed using the XPIO_VREF primitive in conjunction with IBUFE3.

I/O attributes that do not impact the logic function of the component, such as IOSTANDARD, and IBUF_LOW_PWR, should be supplied in XDC or to the top-level port via an appropriate property. For details on applying such properties to the associated port, see the Vivado Design Suite Properties Reference Guide (UG912). Attributes that impact the functionality, such as SIM_INPUT_BUFFER_OFFSET, must be supplied to the component via a generic_map (VHDL) or parameter (Verilog) to have the correct simulation behavior.

Port Descriptions

Port	Direction	Width	Function
I	Input	1	Diff_p Buffer Input. Connect to top-level p-side input port.
IBUFDISABLE	Input	1	Disables input path through the buffer and forces to a logic Low. This feature is generally used to reduce power at times when the I/O is idle for a period of time.
O	Output	1	Buffer output
OSC<3:0>	Input	4	Offset cancellation value
OSC_EN	Input	1	Offset cancellation enable
VREF	Input	1	Vref input from HPIO_VREF

Design Entry Method

Instantiation	Yes
Inference	No
IP and IP Integrator Catalog	No

Available Attributes

Attribute	Type	Allowed Values	Default	Description
SIM_DEVICE	STRING	"VERSAL_PRIME", "VERSAL_PRIME_ES1", "VERSAL_PRIME_ES2"	"ULTRASCALE"	Set the device version for simulation functionality.
SIM_INPUT_BUFFER_OFFSET	DECIMAL	-50 to 50	0	Offset value for simulation purposes.
USE_IBUFDISABLE	STRING	"FALSE", "T_CONTROL", "TRUE"	"FALSE"	Set this attribute to "TRUE" to enable the IBUFDISABLE pin.

VHDL Instantiation Template

Unless they already exist, copy the following two statements and paste them before the entity declaration.

Library UNISIM;
use UNISIM.vcomponents.all;


-- IBUFDSE3: Differential Input Buffer with Offset Calibration
--           Versal Prime series
-- Xilinx HDL Language Template, version 2021.1

IBUFDSE3_inst : IBUFDSE3
generic map (
   SIM_DEVICE => "VERSAL_PRIME", -- Set the device version for simulation functionality (VERSAL_PRIME,
                                 -- VERSAL_PRIME_ES1)
   SIM_INPUT_BUFFER_OFFSET => 0, -- Offset value for simulation (-50-50)
   USE_IBUFDISABLE => "FALSE"    -- Enable/Disable the IBUFDISABLE pin (FALSE, TRUE, T_CONTROL)
)
port map (
   O => O,                     -- 1-bit output: Buffer output
   I => I,                     -- 1-bit input: Diff_p buffer input (connect directly to top-level port)
   IB => IB,                   -- 1-bit input: Diff_n buffer input (connect directly to top-level port)
   IBUFDISABLE => IBUFDISABLE, -- 1-bit input: Buffer disable input, high=disable
   OSC => OSC,                 -- 4-bit input: Offset cancellation value
   OSC_EN => OSC_EN            -- 2-bit input: Offset cancellation enable
);

-- End of IBUFDSE3_inst instantiation

Verilog Instantiation Template


// IBUFDSE3: Differential Input Buffer with Offset Calibration
//           Versal Prime series
// Xilinx HDL Language Template, version 2021.1

IBUFDSE3 #(
   .SIM_DEVICE("VERSAL_PRIME"), // Set the device version for simulation functionality (VERSAL_PRIME,
                                // VERSAL_PRIME_ES1)
   .SIM_INPUT_BUFFER_OFFSET(0), // Offset value for simulation (-50-50)
   .USE_IBUFDISABLE("FALSE")    // Enable/Disable the IBUFDISABLE pin (FALSE, TRUE, T_CONTROL)
)
IBUFDSE3_inst (
   .O(O),                     // 1-bit output: Buffer output
   .I(I),                     // 1-bit input: Diff_p buffer input (connect directly to top-level port)
   .IB(IB),                   // 1-bit input: Diff_n buffer input (connect directly to top-level port)
   .IBUFDISABLE(IBUFDISABLE), // 1-bit input: Buffer disable input, high=disable
   .OSC(OSC),                 // 4-bit input: Offset cancellation value
   .OSC_EN(OSC_EN)            // 2-bit input: Offset cancellation enable
);

// End of IBUFDSE3_inst instantiation

Related Information

Versal ACAP SelectIO Resources Architecture Manual (AM010)