maybe that works / help you
<?php
$post_ID = get_the_ID();
$parentpost_id = wp_get_post_parent_id( $post_ID );
$attachment_id = get_field( "broschuren-download", $parentpost_id ); //use parents-post field: "broschuren-download"
$url = wp_get_attachment_url( $attachment_id );
$title = get_the_title( $attachment_id );
?><div class="pdf-download"><a href="<?php echo $url; ?>" >Broschüre herunterladen</a></div>
