Renesas' radiation hardened high precision operational amplifiers feature low noise, low offset voltage, low input bias current, and low temperature drift making them the ideal choice for applications requiring both high DC accuracy and AC performance.


ISL70444SEH Quad, Rail-to-Rail, Rad Hard Op Amp

The ISL70444SEH quad, rail-to-rail, rad hard op amp combines exceptional AC and DC accuracy, bandwidth performance and the industry's most trusted radiation assurance testing.


Hi, my name is Kiran Bernard, and I'm an applications engineer here at Intersil Corporation.

When considering which op amp works best in your application, a couple of things that you usually think of is, number one, does this device give me the accuracy I need in AC or DC performance? Does it have enough bandwidth for my application? And how do those parameters that I care about shift over radiation?

What we've done here with our new device is that we've combined the best of all three worlds for you, so that you no longer have to choose. So, is this part accurate? Well, when it comes to DC, the VOS of this part at mid-supply is 300µV. When you consider the entire common mode input voltage range, we're looking at 400µV, and that number stays pretty stable across radiation as well. So, in an AC scenario, you've got the slew rate response, which handles the large signal steps, or the small signal response, which you can see here against the competitor "T". You can see that our part has minimal overshoot during the transition, and it also settles a lot faster the final value. For slew rate response, the part is able to keep up with the output with minimal error.

So here on the bench, we've actually got both the devices here. We've got our Intersil's ISL70444SEH alongside competitor "T". We've got the power supply here, which is feeding both the parts, and a signal generator and a scope here, which is monitoring both the input and the output. So here, we've got the input signal to both these op amps here at 300kHz, at a peak-to-peak voltage of 500mV. And we've got the Intersil part in blue, and the competitor "T" in red. The yellow here is the input signal that we're feeding into both the op amps. Here you can see that both op amps are producing somewhat of a square wave, with the Intersil part doing a better job. But, let's crank up the frequency, and see what happens.

So, I'm gonna crank it up to 400, 500kHz. Let's go a little bit faster. And now we're sitting at 1MHz. And you can actually see the competitor "T" starting to lose the definition of the square wave that we're feeding into the op amp, whereas the Intersil part here is still as able to retain the square shape of the input.

When it comes to total ionizing dose, the ISL770444 doesn't really move a whole lot across radiation. It is rated for 300krad at a dose rate of 50 to 300rads per second, and 100krad at a dose rate of 10mrads per second, at initial characterization. Each wafer that we ship is assurance tested to 50krad, low dose rate. We've also done extensive SEE testing. We don't experience burnout all the way up to ±21V on the supply, which is actually the absmax for the process this part is built on, and thanks to Intersil's SOI construction of the PR40 process, it is immune to single-event latchup. And if your application requires high DC accuracy, along with superior AC performance, this part is for you.