Xilinx
TM
Block Preview

Introduction

This block computes the square root of IEEE 754 floating-point values using the Xilinx Floating Point IP core. The component supports Time Multiplexing (TM): multiple parallel computation units share the same clock cycle.

On every rising edge of CLK, if DIN_VLD = 1 and DOUT_RDY = 1:

$$ \mathrm{DOUT}(n) = \sqrt{\mathrm{DIN}(n)} $$

Pin Description

DIN Input Variable bit TM
Floating-point input, always TM. Must be non-negative.
Default: Must be connected
DIN_VLD Input 1 bit BIT
Input data valid.
DIN_RDY Output 1 bit BIT
Input ready output.
CLK Input 1 bit BIT
Global clock.
Default: Default Board Clock
DOUT Output Variable bit TM
Square root output. Valid after 29 cycles.
DOUT_VLD Output 1 bit BIT
Output data valid.
DOUT_RDY Input 1 bit BIT
Downstream ready signal.

Properties

Property window

TM Factor TMFactor

Time Multiplexing factor (number of phases)

Number of TM phases (1 – 32).

Default: 4

Range: 1 – 32

Float Format FloatFormat

Select between single precision 32 bit and double precision 64 bit

Single or Double precision.

Default: Single

Options: Single Double

Cycle per operation II

Number of clock cycles to execute a division. Set to 1 to perform division in realtime. Higher number reduce the area usage of the block

Initiation Interval (1 – 25). Trade-off between throughput and area.

Default: 1

Range: 1 – 25

Functional description

Wraps Xilinx Floating Point IP (operation type: Square_root) with N parallel instances for TM support.

Mathematical background

Square root function:

$$ y = \sqrt{x} $$

Properties:

  • $\sqrt{0} = 0$
  • $\sqrt{1} = 1$
  • $\sqrt{x^2} = |x|$
  • $\sqrt{xy} = \sqrt{x} \cdot \sqrt{y}$ (for $x, y \geq 0$)
  • Undefined for $x < 0$ (returns NaN)

Timing

Fixed latency of 29 clock cycles per phase.

Property Latency (cycles)
Square Root 29

Initiation Interval (II)

Range: 1 – 25 cycles. Higher values reduce area usage.

Typical use cases

  • Magnitude calculations (Euclidean distance)
  • RMS computation
  • Standard deviation
  • Complex number magnitude
  • Normalization