Empty Pdf file generated with FPDF library in WordPress plugin - pdf-generation

Question

I am currently implementing a pdf export functionality within a wordpress plugin i'm developing but the pdf file generated when i click on export button is empty. To implement the export i use FPDF library
Ive put the code which uses FPDF in a function which is executed by the wp_ajax_ action hook. Here is the code:
<?php
require_once plugin_dir_path( __FILE__ ) . 'fpdf/fpdf.php';
function pdf_pull_wpse_212972() {
$pdf = new FPDF('p','mm','a4');
$pdf->SetFont('arial','b',14);
$pdf->AddPage();
$pdf->Cell(40,10,'Referrer URL',1,0,'C');
$pdf->Cell(40,10,'User IP Address',1,0,'C');
$pdf->Cell(40,10,'User Agent',1,0,'C');
$pdf->Cell(40,10,'Browser',1,0,'C');
$pdf->Cell(40,10,'OS',1,0,'C');
$pdf->Output();
wp_die();
}
add_action('wp_ajax_pdf_pull','pdf_pull_wpse_212972');
Here is the jQuery code executed when i click on the export button
jQuery(document).ready(function($) {
jQuery('#pdf-export-btn').click(function(){
var data = {
'action': 'pdf_pull',
};
jQuery.post(tclisecure.ajax_url, data, function(response) {
var downloadLink = document.createElement("a");
var fileData = [response];
var blobObject = new Blob(fileData,{
type: "application/pdf"
});
var url = URL.createObjectURL(blobObject);
downloadLink.href = url;
downloadLink.download = "tracked_info.pdf";
/*
* Actually download PDF
*/
document.body.appendChild(downloadLink);
downloadLink.click();
document.body.removeChild(downloadLink);
});
});
});