Gate Current Maximum for Qorvo Amplifiers

RF Solutions RF Power Amplifiers
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I have been having some difficulty understanding how to design the Vg (Gate Voltage) supply for Qorvo power amplifiers. Most of these amps require a -5V, which could be easily supplied by a DAC or dual rail supply if the current draw is small. However, Qorvo amplifiers usually have two figures for gate current draw. For example, take the TGA2214-CP amplifier. The absolute maximum rating table refers to the figure on page 8 of the datasheet. That figure shows a curve for the total current and the current for each stage. The figure starts at 125C and is over 120 mA. If we project the nonlinear curve to a room temperature startup temperature, then we would be at several amps of current needed. I am pretty sure that is not correct.

Now lets assume we are going to transmit at 10 GHz on the TGA2214-CP amplifier. If l look at the curves on page 6 of the datasheet, it says that at 25C the gate current draw will be 2mA for 10 GHz. So the curves on page 6 don’t agree with those on page 8. That is, unless there is a surge of current for a few nanoseconds. Is that what page 8 is showing me? If so, what is the real time? And what is the actual peak draw for room temperature? A circuit to power amps worth of negative voltage is a lot more complicated and expensive than a few milliamps of draw.

Any help understanding the differences in Gate Current on page 6 and 8 would be greatly appreciated. I see this for most of the Qorvo amps, so it would be great to understand this.

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Hello. The "Absolute Max. Gate Current " curve in our GaN PA datasheets can be confusing. It shows the electromigration limit for gate current reliability and absolute max. value (more of a theoretical maximum). The curves on page 6 (“Gate Current vs. Freq. vs. Temp.” and “Gate Current vs. Input Power vs. Freq.”) represent actual operating current. Hope this helps.

1 Like
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Thanks for you quick reply. So I have two amplifiers, a TGA2214-CP and a TGM2635-CP and I was looking to build a circuit that I could use for either amp. If I supplied up to 20 mAmp of current to the Gate, would you think this design would cover the inrush and actual operating current at 10 GHz for these two amps? This assumes I’m staying below the max RF input and stay within temp bounds.

I’m just being cautious because I had inrush current toast one of my amps from another vendor (that I no longer use).

Thanks.

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Hello. I would like to get you various app notes (and answer your question at the same time). Could you please email appsupport@qorvo.com? We could get all of that to you and also bring others in your region. Thanks!

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Just sent the email. Thanks.