I have evaluated ADL5330. Could anyone comment on my question as below.
I first used AD8367 as AGC to have 180~360MHz output together with AD8362(RF Det) and AD820(OP Amp). It is working fine, no problem at all.
Next I used ADL5330 to have higher output frequency (1GHz~2.5GHz) withe the same AD8362 and AD820. It is working fine. However the device(ADL5330) is very very hot that I cannot keep touching.
I really fear the derating issue to be corrupted in 1 year. The board (4layer 1.6mm thick, 3inch x 2.5inch) itself is also warm. I prepared ground plane under the device (not soldered withe devices's exposed paddle) which has a via hole (0.4mm diameter). The input power is -6dBm and Vg is 0.374V~0.92V. So the current might be 200mA max according to the data sheet, which means that 5V*0.2 = 1W. The thermal resistance is 60℃/W provided that it is soldered. So the junction temerature can be less than 100℃.
Do I definately need soldering for the device with the groung plane?? ( I hesitate because I need metal mask as BGA to increase the cost.)
Is there any data for the thermal resistance in case of no soldering (only touched with the ground plane)?
I welcome any comments!! Thanks.
For both RF performance and adequate heat removal, the thermal pad on the ADL5330 really needs to be soldered to the gnd plane of the PCB,