The AMC1203 is a 1-bit, 10MHz, isolated delta-sigma (ΔΣ) modulator with an output buffer separated from the input interface circuitry by a silicon dioxide (SiO2) isolation barrier. This barrier provides galvanic isolation of up to 4000VPEAK. Used in conjunction with isolated power supplies, these devices prevent noise currents on a data bus or other circuits from entering the local ground and interfering with or damaging sensitive circuitry.
The AMC1203 modulator operates from a +5V supply with a dynamic range of 95dB. The differential inputs are ideal for direct connection to shunt resistors or other low-level signal sources. With the appropriate digital filter and modulator rate, the device can be used to achieve 16-bit analog-to-digital (A/D) conversion with no missing codes. An effective resolution of 14 bits and an SNR of 85dB (typical) can be maintained with a sinc3 filter with a decimation ratio of 256.
The modulator output is translated to a balanced signal and then transferred by the capacitive isolation barrier. Across the isolation barrier, a differential comparator receives the logic transition information, and then sets or resets a flip-flop and the output circuit accordingly.
The AMC1203 is available in SOP-8 gull-wing, SOP-8, and SOIC-16 packages. The AMC1203 is characterized for operation over the ambient temperature range of –40°C to +105°C.