Olin Lathrop wrote:
> N. T. wrote:
>> Yes. You can use LTC2053 instead of LT1168.
>> LTC2053:
>> CMRR is typically 116dB.
>> Average Input Offset Current s typically =A01nA.
>>
>> LT1168
>> CMRR 90dB Min
>
> How is that supposed to help with a DC bias voltage problem? =A0What he n=
eeds
> it high pass filtering, which has nothing to do with the common mode
> rejection ratio of the instrumentation amp.
>

Yes, I over-truncated the specs, my mistake..
---
The LTC2053 is a high precision instrumentation amplifier. The CMRR is
typically 116dB with a single or dual
5V supply and is independent of gain. The input offset voltage is
guaranteed below 10=B5V with a temperature
drift of less than 50nV/=B0C
---
The LT1168 is laser trimmed for very low input offset voltage (40=B5V
max), drift (0.3=B5V/=B0C)
---

VG wrote: "The output from my ECG (instrumentation amplifier) has
somewhat of a DC bias to it." I believe he meant that the mean value
of the output waveform is not close enough to 0. The reason, I think,
is input offset voltage and temperature drift.

LTC2053 input offset voltage is below 10=B5V with a temperature drift of
less than 50nV/=B0C
LT1168 input offset voltage is 40=B5V max, drift is 0.3=B5V/=B0C.

That's why I suggested using LTC2053 instead of LT1168.

--=20
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