# Need Help with a INA Amplif

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#### Giovanni

Joined May 20, 2008
4
Hi everybody, i'm new on this forum; i'm in need of help using an INA 52063. I use it as a 2nd stadium after a transimpedance amplifier and the problem is that when i turn on the DC generator the amplifier heats up and breaks .

The layout used is the same shown in the application notes of the datasheet, and the supply is +5V. I've also added a 50 ohm parallel resistor at the output for impedance matching.

Thanks for the help^^

#### SgtWookie

Joined Jul 17, 2007
22,220
What is your input signal level?

What is the thickness of your PCB?

If you're up in the GHz region, you'll have to plan your PCB traces pretty carefully to get a good impedance match.

#### Giovanni

Joined May 20, 2008
4
What is your input signal level?

What is the thickness of your PCB?

If you're up in the GHz region, you'll have to plan your PCB traces pretty carefully to get a good impedance match.
For my application i need to work around 20/30 Mhz so i use a 20 MHz 100mVpp input signal for testing. Do you think it could be a matching problem?
My PCB is a double sided approx 1.5 mm thick...

#### SgtWookie

Joined Jul 17, 2007
22,220
100mV pp? That's what's killing it.
Absolute maximum input power is +13 dBm, or 4,467 uV.
You're feeding it 40 dBm, or 100,000uV.

#### Giovanni

Joined May 20, 2008
4
100mV pp? That's what's killing it.
Absolute maximum input power is +13 dBm, or 4,467 uV.
You're feeding it 40 dBm, or 100,000uV.
How do you obtained these values? I thought +13dBm was equal to 1V ( 10^(13/10) => approx 20 mW so V=sqrt(20mW*50ohm) => approx 1V)

However i've noticed that even if i don't give a singnal in input, when i supply the IC it burns out even at +4V... help!

#### beenthere

Joined Apr 20, 2004
15,819
Can you post the layout of your printed circuit board and indicate the component values? The schematic would be helpful as well.

The chip burning with no signal makes it likely that it is going into a destructive oscillation, possibly due to layout or wrong value components.

#### JoeJester

Joined Apr 26, 2005
4,390
dBm is referenced to 1 milliwat. 100,000 uV is neg 7 dBm (-6.9897).

#### Giovanni

Joined May 20, 2008
4
Non-productive comment removed.

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#### hgmjr

Joined Jan 28, 2005
9,029
..........

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#### Dave

Joined Nov 17, 2003
6,970
Some people in life speak foreign languages; for everyone else there's Babel Fish.

Dave

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