ADRF5144 input power

HI Taehwan,

Could you please also specify the power conditions you will apply to the ADRF5144 at 25C? Is it CW signal or pulsed signal? If pulsed signal, what would be the duty cycle and the pulse width? 

Regards,

Zheng

Hi Zheng,  The type of signal is Pulse signal , the duty cycle is 0.3%  , : period is 500us,  width is 0.200us.

Sincerely

Taehwan Choi

oh sorry about dutycycle. duty cycle is 15% (PRI : 8us, PW 1.2us). you need to consider about heat.

Hi Taehwan,

For such wide PW and high duty cycle, you need to refer to the max recommended RF input power for pulsed conditions in Table 1, which is 43dBm max at Tcase = 85C.

Even if your Ta = 25C, due to PCB design, heatsink design, thermal dissipation efficiency, etc. you need to verify the case temperature (at Epad) will not exceed 85C. You can try to use infrared thermal camera to check the temperature directly from the top. As you mentioned, 44dBm from HPA would be a problem to cause damage to ADRF5144.

Generally speaking, please always refer to max rec. RF input power in Table 1. Operating at AMR table 2 will cause reliability issues or instantaneous damage.

Zheng

Hi Zheng.

Thank you for your detailed reply.

I am late, I am so sorry.

I had checked RF input power for pulsed conditions in Table 1, which is 43 dBm max at Tcase = 85degC.
As your mention for thermal management, if thermal management is good that the temperature directly from the top is 25~50degC, I thought max RF input power is over 43dBm. So, I wonder what Max RF input power is at about 50degC?

if it is not guaranteed, Can you recommend RF switch over 43dBm RF input power value?

Sincerely,

Taehwan Choi.

Hi Taehwan,

In table 1, the 43dBm max at Tcase = 85degC is for the 50Ohm system. In your application circuit, ADRF5144 is connected to a PA. Normally, the matching of PA is not perfect. Therefore, the mismatch will also cause some power derating. For the detail, please refer to the apps note: AN-2558: RF Switch Performance with Arbitrary Loads | Analog Devices

Zheng

Hi, Zheng.
Thank you for application note.
I got to know RF Switch's S parameter is changed, referring to the note.

But, Our Impedance of PCB is guessed from 45ohm to 55ohm. So I don't think insertion loss is bigger than about 1.2dB(@ return loss <-10dB).

if PCB's impedance  is made  worse in force, I think insertion loss is bigger and this chip can avoid the damage.
but it is not normal way.

Can you recommend another RF switch over 43dBm of RF input power value?

Thank you for your kindly.

Sincerely.

Taehwan Choi.

what's your frequency range? Any other requirements than 43dBm RF input powe value?

the range of frequency is 9G ~10GHz. I want to use low insertion Loss under 1dB.
I hope other specifications are same or better than ADRF5144.

the range of frequency is 9G ~10GHz. I want to use low insertion Loss under 1dB.
I hope other specifications are same or better than ADRF5144.

23.12.13

Are there better Items?.. 

I look forward your reply.

we currently do not have the solution. Please stay tuned.

HI,ZWANG
I want to know if the marking of ADRF5144BCCZN is S5G?The data sheet doesn't talk about marking.
Look forward to your reply,
the most sincere greetings.

HI,ZWANG
I want to know if the marking of ADRF5144BCCZN is S5G?The data sheet doesn't talk about marking.
Look forward to your reply,
the most sincere greetings.