How do I know that I'm biasing the AD8235/AD8237 correctly?

Hi,

I have a question regarding the content of the AD8235 data sheet.

There is a description of (0.01V, 0.026V) (4.994V, 0.076V) in Figure 21 on page 11 the data sheet.

Is it correct (0.01V, 0.26V) (4.994V, 0.76V)?

Best Regards,

It seems the LTspice model for the AD8235 has an offset voltage of ~0.9mV on the input.  All my sims have an output voltage about 0.9mV*Gain higher than calculated.  Is this an offset built into the model that accounts for a typical offset of the amp?  Or…

Hi,

I have the following circuit. I'm not sure if it is clear or fuzzy. But anyway, I have oscillations of about 1Hz at the output without any input signal. Do you have any idea what the problem is with the circuit?

Hello AD engineers,

Two information are missing on the AD8235 datasheet:

- How long shall it takes to come back from shutdown. In simulation model it is pretty quick < 10µs then it start a normal behavior from VCC/2 (ref = Vneg = 0V, Vpos = VCC =…

Dear Sir/Madam,

Our customer asked the following questions.

1)What is the t1 and t2 time when AD8235 shutdown? (Refer to the following figure)

2)When AD8235 is shudowning, what is the Vout condition? Impedance high, correct?

I could not catch these…

Hi,

I've been using the AD8236 to make an EMG amplifier. I connected a second order low pass MFB butterworth filter at @20Hz cutoff , which filters the AD8236 output and feeds it to the reference pin. I am not pleased with the results. while the DC correction…

Figure 44 of the AD8235 Data sheet shows the device paired with AD8609 in a hi-pass configuration with break at 0.3 Hz.  The AD8609 has very high voltage noise at this frequency.  Fundamental of Heart Beat is about 1 Hz with content to about 60 Hz.

As…