Create subquery in WHERE

I have subquery like this its working, how i can rewrite with active record?

$builder->where("(SELECT SUM(sum) FROM payments WHERE visit = v.id) > 0");


Like this

$SubQuery = $this->db->table('payments ')->select('SUM(sum)')->where('visit = v.id');


$MainQuery = $this->db->table('visits')->where("$SubQuery > 0")