Amplifying the signal of pressure transmitters, or high-gain sensor interfaces, influences the signal and the noise, therefore, the achievable effective resolution with a signal chain is also influenced. In the case of sensing signals in the single-digit mV region, where the signal has to be multiplied manifold, the noise introduced by the amplification must be monitored closely.

Figure 4-3 shows the dependency of the noise in LSB and the resulting effective resolution versus the amplification factor of the internal OPA of the MSPM0. Notably, the total amplification of the signal is calculated by multiplying the amplification of the external INA350 with this internal gain factor. The measurements are conducted with the 64x averaging and an effective sampling rate of 62.5kSPS.

As shown in Figure 4-3 the noise scales linearly with the amplification factor. The achievable effective resolution for the complete signal chain remains at 8.32 bits when using a 16x amplification factor, which results in a total amplification of 800. This resolution is still usable for detecting jumps in a signal and is capable of reducing the effective sample rate to increase the effective resolution, as described in Section 4.3.