Downpayment at whole Purchase order level

Hi Expets,

Good day!!

I have a sceneario, downpayment to be create at purchase order level not on purchase order line item level. Downpayment is belongs to whole purchase order level.

As per sap standard system is asking Item to be entered (mandatory) when we assiging the purchase order at downpayment docuemnt.

My business requirement is downpayment should be at whole purchase order level and not item level (if i have 100 line items in a purchase order business does not want to create 100 downpayment document,) single downpayment document and to be tracked in purchase order.

Plesae guide me any configuration or work around solution.

Regards

Chandu