The ISO ADC Click is add-on board current-shunt measurement device with isolated delta-sigma modulator. This Click board™ is based on AMC1204BDWR provide a single-chip solution for measuring the small signal of a shunt resistor across an isolated barrier from Texas Instruments. ISO ADC Click contains shunt resistor, these types of resistors are typically used to sense currents in motor control inverters, green energy generation systems, and other industrial applications.

ISO ADC Click is supported by a mikroSDK compliant library, which includes functions that simplify software development.

The ISO ADC Click is current sensing system, which includes isolated delta-sigma modulator. The main IC on the ISO ADC Click is AMC1204BDWR, from Texas Instruments.The current-sensing shunt resistor is designed as a 4 wire connected resistor that enables accurate measurements through a force-sense connection. The AMC1204BDWR differential inputs easily connect to the shunt resistor, An internal reference eliminates the need for external components.

The Click board™ communicates with the target microcontroller over SPI interface on the mikroBUS™ line. The analog input range is tailored to directly accommodate the voltage drop across a shunt resistor used for current sensing. The SiO2 -based capacitive isolation barrier supports a high level of magnetic field immunity as described in the Digital Isolator Magnetic-Field Immunity application report. The external clock input simplifies the synchronization of multiple current sense channels on system level. The extended frequency range of up to 20 MHz and is provided externally at the CLKIN pin. The data are synchronously provided at 20 MHz at the DATA output pin. The data are changing at the falling edge of CLKIN.

The ISO ADC Click perform current measurement on LOAD connector, the AMC1204BDWR measure the differential input signal VIN = (VINP – VINN) on two ends of the shunt resistor,against the internal reference of 2.5 V using internal capacitors that are continuously charged and discharged.The current measurement can’t be possible without external power supply on AVDD connector.

The voltage level of the logic section can be selected via VCC SEL jumper, between 3.3V and 5V. This allows for both 3.3V and 5V capable MCUs to use the SPI communication lines properly.

• Interface: SPI
• Compatibility: mikroBUS™
• Dimensions: 42.9 x 25.4mm
• Input Voltage: 3.3V or 5V
• Voltage supply (AVDD): Min. 4.5V, Typ. 5V, Max. 5.5V
• Current (LOAD): 3A
• CLKIN: Min. 0MHz, Max. 20MHz

• Schematic
• AMC1204 Datasheet
• mikroSDK
• LibStock