Codeigniter Insertar datos MSSQL

 $data=array('id ' => CONVERT(BINARY(16),$username, 1), 'password' => 
              CONVERT(BINARY(16),$password, 1), 'Email' => $email, 'accounttype' 
             =>0,'birthdate' => '2011-11-11 00:00:00','pin' => $pin, 'fb_id' => 
             $fb_id );
        

return (($this->mssqlu->insert('tbl_account', $data)) ? $this->mssqlu->insert_id() :Falso);