SQL prepare statement error

I have Apache2, php 7.2, and mysql installed. At the top of my index.php I have the following script:

<?php
session_start();
// start of script every time.

//  setup a path for all of your canned php scripts
$php_scripts = '/home/larry/web/test/php/'; // a folder above the web accessible tree
//  load the pdo connection module  
require $php_scripts . 'PDO_Connection_Select.php';
require $php_scripts . 'GetUserIpAddr.php';

//*******************************
//   Begin the script here
$ip = GetUserIpAddr();
if (!$pdo = PDOConnect("foxclone")):
{
    echo "Failed to connect to database" ;
    exit;
}
else:
{
    $stmt = $pdo->prepare("INSERT INTO 'download' ('IP_ADDRESS', 'FILENAME') VALUES (?, ?");
    $stmt->bindParam(1, $ip);
    $stmt->bindParam(2, $filename);  
    $stmt->execute();

}

endif;
//exit();
?>

<DOCTYPE html>

The prepare statement is throwing the following error:

Fatal error: Uncaught PDOException: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''download' ('IP_ADDRESS', 'FILENAME') VALUES (?, ?' at line 1 in /home/larry/web/test/public_html/index2.php:23 Stack trace: #0 /home/larry/web/test/public_html/index2.php(23): PDO->prepare('INSERT INTO 'do...') #1 {main} thrown in /home/larry/web/test/public_html/index2.php on line 23

I'd appreciate some help on this.