SBAU386 August 2021 AMC1350 , AMC1350-Q1 , AMC1351 , AMC1351-Q1
The analog output from the AMC1350EVM and AMC1351EVM is a fully differential signal centered at 1.44 V. Figure 2-2 shows that the differential output of the AMC1350 or AMC1351 is available on the two screw terminals of J4. OUTP is available at J4.3 and swings from 0.5 V to 2.5 V when a –5-V to 5-V signal is applied to the input of the AMC1350 or from 1.44 V to 2.5 V when a 0-V to 5-V signal is applied to the input of the AMC1351. OUTN is available at J4.2 and swings from 0.5 V to 2.5 V when a –5-V to 5-V signal is applied to the input of the AMC1350 or from 0.5 V to 1.44 V when a 0-V to 5-V signal is applied to the input of the AMC1351. The pads of R2, R4, C9, C7, and C12 allow users to install their own output filtering. Table 2-1 lists a few example filters. Common-mode filter capacitors C7 and C12 are recommended to be at least 20x less than the differential filter capacitor.
Cutoff Frequency | Resistance | Differential Capacitor |
---|---|---|
100 kHz | R2 = R4 = 100 Ω | C9 = 8.2 nF |
300 kHz | R2 = R4 = 100 Ω | C9 = 2.7 nF |
600 kHz | R2 = R4 = 100 Ω | C9 = 1.3 nF |
Use the differential output if the application allows. If a single-ended output is desired, consult the Interfacing a Differential-Output (Isolated) Amplifier to a Single-Ended Input ADC application report for help designing the differential to single-ended circuit.