I have several projects I would like to try an instrumentation amp on(mostly power supplies). Anyone have a favorite part number they would care to share?

 

What power and common-mode voltage range do you need and is the power from a single or dual supplies?

 

One of my design staples is a pseudo ground, low PS voltage is a plus, as is a higher voltage tolerance. Got me a new toy, my old one died after the years of disuse. Cheaper too...

 

Here is one we used in some of our products.

https://www.ti.com/lit/ds/symlink/i...42400&ref_url=https%3A%2F%2Fwww.mouser.com%2F

I don't really know if it will be suitable for your purposes or not, and they seem more expensive than I remember in small quantities. You might do better to build one using 3 amplifiers in a quad package.

 

Yep, pretty pricey at $11.68 ea. Think I'll pass on that one.
https://www.mouser.com/ProductDetai...=/ha2pyFaduibIK9rTMfnyxfAyy8PyQt5o9wm8wiFlfA=

Any other candidates?

I might use your suggestion eventually, to play.

 

hi W,
I find the AD623 is a low cost, single supply IA.
E
Clip:
Although the design of the AD623 was optimized to operate from a single supply, the AD623 still provides superior performance when operated from a dual voltage supply (±2.5 V to ±6.0 V).

 

At $6.31 ea.much more likely to try out..
https://www.mouser.com/ProductDetail/Analog-Devices/AD623ANZ?qs=NmRFExCfTkFNc5Hlpv4LKQ==

So, could you show me how to use this device to measure current across a resistor? Figure in the range of 0.1VDC to 1.0VDC. Unity gain or x10 Gain?

 

hi,
Is the Rsense resistor in the Low side of the project.?
What is value of the Rsense resistor.?

It would create a LTSpice simulation of a suitable circuit, if required.

E

 

I have several projects I would like to try an instrumentation amp on(mostly power supplies). Anyone have a favorite part number they would care to share?

Two that I've used often are the LT1789 and the LT1167.

 

If your measuring voltage across a power supply sense resistor, I'd really reccomend an OP amp designed for the job.

I had to convert 0-40V to 0-5V and measure the voltage across a sense resistor in the + output of a seven KIK power supplies. The 0-5 control input was relative to the plus output. Isolation amplifiers were required.

When I wanted to order a power supply with isolation amplifiers built in (optional), it was a $500.00 USD option for a $1500.00 power supply. It was turned down. The hope was to be able to display power in the future.