AMC7823: Used for RF Power Amplifier Negative Supply Control

Hi Allan,

The AMC7823 does not support negative operation.  You would have to put some kind of negative offset op amp buffer for this.  I think you would be better off using a device like the AMC7834 or the AMC7904.

Thanks,

Paul

The documentation for the AMC7904 is on the ti.com/mysecuresoftware page.  The customer can request access by clicking the following link:

https://www.ti.com/licreg/docs/swlicexportcontrol.tsp?form_id=257238&prod_no=AMC7904-DESIGN&ref_url=asc_dc_dac

The AMC7904 has integrated switches for TDD applications for PA biasing.  It uses a temperature sensor and look-up table to provide PA bias compensation.  The AMC7834 does not have integrated switches, but uses a current shunt monitor for PA bias compensation.

Both support negative voltage operation.

This article describes how to create a negative offset for PA biasing using a positive output dac.

Unipolar negative voltage source from unipolar DAC circuit

Thanks,

Paul