class Database {

    private static $cont = null;

    public function __construct() {
        exit('Init function is not allowed');
    }

    public static function getCadena() {
       $ini = parse_ini_file('C:credenciales.ini', true);
       return "host='" . $ini['server']['host'] . "' port='" .
       $ini['server']['port'] . "' dbname='" . $ini['server']['database'] .
       "' user='" . $ini['server']['user'] . "' password='" . $ini['server']
       ['pass'] . "' ";
    }

    public static function connect() {
         $ini = parse_ini_file('C:credenciales.ini', true);
         if (null == self::$cont) {
            try {
               self::$cont = new PDO("pgsql:host=" . $ini['server']['host']
               . ";port=" . $ini['server']['port'] . ";" . "dbname=" .
               $ini['server']['database'], $ini['server']['user'],
               $ini['server']['pass']);
            } catch (PDOException $e) {
              die($e->getMessage());
            }
          }
          return self::$cont;
       }

       public static function disconnect() {
           self::$cont = null;
       }

$pdo = Database::connect();
    $nombrefiltrar = strtoupper($_POST['nombreconductorfiltro']);
    $sql = " SELECT c_cedula, c_nombre, c_activo FROM conductor WHERE c_nombre LIKE '%" . $nombrefiltrar . "%'
            ORDER BY c_nombre ASC";
    foreach ($pdo->query($sql) as $row) {
        echo '<tr>';
        echo '<td>' . $row['c_cedula'] . '</td>';
        echo '<td>' . $row['c_nombre'] . '</td>';
        if ($row['c_activo'] == TRUE) {
            echo '<td> ACTIVO </td>';
        } else {
            echo '<td> INACTIVO </td>';
        }

        $conductor = "javascript:verEditarConductor(" . $row['c_cedula'] . ", '" . $row['c_nombre'] . "', " . $row['c_activo'] . ")";
        echo '<td><a href="' . $conductor . '" class="btn" style="background-color: #004D27" ><img src="png/edit.png"  alt="x" title="Ver" style="background-color: #004D27" /></a>';
        echo '</tr>';
    }
    Database::disconnect();
    echo '</tbody>
            </table>';
    break;

:nombre

$nombrefiltrar = strtoupper($_POST['nombreconductorfiltro']);

$sql = $pdo->prepare(" SELECT c_cedula, c_nombre, c_activo FROM conductor
         WHERE c_nombre LIKE :nombreFiltrar
         ORDER BY c_nombre ASC");

$sql->bindParam(":nombreFiltrar", $nombreFiltrar, PDO::PARAM_STR);

$sql->execute();

$sql->execute(array(":valorUno" => $valorUno, ":valorDos" => $valorDos,
                    ":valorTres" => $valorTres));

$resultado = $sql->fetchAll(PDO::FETCH_ASSOC);

foreach($resultado as $value){
    echo $value["nombreColumna"];
}