php oop and pdo notworking in web hosting

Question

my init.php Here's the code of the connect in hosting but not working

$GLOBALS['config'] = array(
'mysql' => array(
    'host' => '127.0.0.1',
    'username' => 'root',
    'password' => '',
    'db' => 'db'
),
'remember' => array(
    'cookie_name' => 'hash',
    'cookie_expiry' => 604800
),
'sessions' => array(
    'session_name' => 'user',
    'token_name' => 'token'
));?>

and my db.php
Here's the code of the connect in hosting but not working and connect database web hosting, just show blank page in my hosting plz help me.

<?php

 class DB {
private static $_instance = null;
private $_pdo,
        $_query,
        $_error = false,
        $_results,
        $_count = 0,
        $_last_insert_id ;

private function __construct() {
    try {
        $this->_pdo = new PDO('mysql:host=' . Config::get('mysql/host') . ';dbname=' . Config::get('mysql/db'), Config::get('mysql/username'), Config::get('mysql/password') );
        $this->_pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES,TRUE);
    } catch(PDOException $e) {
        die($e->getMessage());
    }
}

public static function getInstance() {
    if(!isset(self::$_instance)) {
        self::$_instance = new DB();
    }
    return self::$_instance;
}